Japan's largest platform for academic e-journals: J-STAGE is a full text database for reviewed academic papers published by Japanese societies

Purpose Study findings can reach a worldwide audience only after a paper is published in the peer-reviewed literature; this is regarded by many as the definitive contribution to global exchange of knowledge. The abstract to publication (A:P) rates for free papers presented at an emergency medicine meeting in Asia has not been investigated before. The purpose of this study was to determine the full publication rate of abstracts presented as oral presentations at the Third Asian Conference on Emergency Medicine (ACEM) in Hong Kong in 2004. Methods A detailed literature search of the MEDLINE database was performed using first and last authors' names and appropriate key words up to January 2008. Results A total of 54 free paper abstracts were presented at this conference as oral presentations. Ten (18.5%) abstracts had subsequently been published as full articles by the end of January 2008. The full-text articles were published in eight different journals. Conclusions The A:P ratio of abstracts for oral presentations at ACEM 2004 was 18.5%, lower than that of similar meetings in the US and Australasia. It is normal for less than half of the abstracts presented at meetings to be published as full papers in refereed journals, largely due to the inability to overcome the barriers that present at each stage towards publication. Lack of researcher time due to pressure of clinical work and English language skills may play an important role in Asia.

The year 2009 marks the centenary of the birth of Otto Scherzer, one of the early pioneers of electron microscopy. Scherzer, shown in Figure 1, was the originator of the famous microscopy theorem that the spherical and chromatic aberrations of rotationally symmetric electron lenses were unavoidable [1]. In honor of this centennial occasion, we organized a special memorial symposium during the Microscopy & Microanalysis 2009 meeting, which was held in Richmond, Virginia, in late July. The introductory talks of the symposium presented a fascinating mix of firsthand accounts about working with Scherzer in Darmstadt and descriptions of the correction concepts and the early corrector prototypes that emerged from his group. Placed in this historical context, the latest advances in aberration correction for scanning and fixed-beam instruments that were presented in this symposium were all the more impressive and conveyed a vivid sense of history in the making. Representative applications of aberration correction to a broad range of materials were also highlighted in platform and poster presentations. Here we give a short account of the emergence of aberration-corrected electron microscopy (ACEM) and very briefly summarize some of the prospects and challenges for this burgeoning field. Further information about these developments, including details of applications, will be found in selected papers from the symposium, which will be published in a forthcoming issue of the journal Microscopy and Microanalysis due to appear in mid-2010.

Tr en Amaç: Gastrik kanser (GK) ve kolorektal kanser (KRK) gibi gastrointestinal ilişkili kanserler, önemli bir halk sağlığı problemi haline gelmiştir ve preoperatif değerlendirme, ilk tedavi stratejilerinin belirlenmesinde oldukça önemlidir. Bu çalışma, GK ve KRK hastalarında preoperatif nötrofil-lenfosit oranı (NLO) ve trombosit-lenfosit oranı (TLO)'nın olası prognostik değerini değerlendirmek için yapıldı. Yöntemler: Bu retrospektif çalışmaya 50 GK, 50 ardışık KRK hastasını ve yaşları eşleştirilmiş 60 ardışık sağlıklı kişi (kontrol grubu) alındı. Preoperatif tam kan sayımı sonuçları (nötrofiller, trombositler ve lenfositler) hastanın tıbbi kayıtlarından alındı. Bulgular: NLO ve TLO değerleri hem GK hem de KRK hastalarında kontrol grubuna göre anlamlı olarak yüksek bulundu (her ikisi de p Giriş ve Amaç: Gastrik kanser (GK) ve kolorektal kanser (KRK) gibi gastrointestinal ilişkili kanserler, önemli bir halk sağlığı problemi haline gelmiştir ve preoperatif değerlendirme, ilk tedavi stratejilerinin belirlenmesinde oldukça önemlidir. Bu çalışma, GK ve KRK hastalarında preoperatif nötrofil-lenfosit oranı (NLO) ve trombosit-lenfosit oranı (TLO)'nın olası prognostik değerini değerlendirmek için yapıldı. Gereç ve Yöntem: Bu retrospektif çalışmaya 50 GK, 50 ardışık KRK hastasını ve yaşları eşleştirilmiş 60 ardışık sağlıklı kişi (kontrol grubu) alındı. Preoperatif tam kan sayımı sonuçları (nötrofiller, trombositler ve lenfositler) hastanın tıbbi kayıtlarından alındı. Bulgular: NLO ve TLO değerleri hem GK hem de KRK hastalarında kontrol grubuna göre anlamlı olarak yüksek bulundu (her ikisi de p Anahtar Kelimeler tr en Mide kanseri, kolorektal kanser, nötrofil-lenfosit oranı, trombosit-lenfosit oranı Gastric cancer, colorectal cancer, neutrophil -to- lymphocyte ratio Kaynakça 1. Sisik A, Kaya M, Bas G, Basak F, Alimoglu O. CEA and CA 19-9 are still valuable markers for the prognosis of colorectal and gastric cancer patients. Asian Pac J Cancer Prev. 2013;14:4289-94. 2. Fu JJ, Baines KJ, Wood LG, et al. Systemic inflammation is associated with differential gene expression and airway neutrophilia in asthma. OMICS 2013;17:187–99. 3. Kemp MW, Kannan PS, Saito M, et al. Selective exposure of the fetal lung and skin/amnion (but not gastro-intestinal tract) to LPS elicits acute systemic inflammation in fetal sheep. PloS One 2013;8:e63355. 4. Coussens LM, Werb Z. Inflammation and cancer. Nature 2002;420: 860–7. 5. Teramukai S, Kitano T, Kishida Y, Kavvahara M, Kubota K, Komuta K, Minato K, Mio T Fujita Y, Yonei T, Nakano K, Tsuboi M, Shibata K, Furuse K, Fukushima M. Pretreatment neutrophil count as an independent prognostic factor in advanced non small celi lung cancer: an analysis of Japan Multinational Trial Organisation LC00-03. Eur J Cancer 2009; 45:1950-8. 6. Yamanaka T, Matsumoto S, Teramukai S, Ishivvata R, Nagai Y, Fukushima M. The baseline ratio of neutrophils to lymphocytes vvith patient prognosis in advanced gastric cancer. Oncology 2007; 73:215-20. 7. Smith RA, Ghaneh P, Sutton R, Raraty M, Campbell F, Neoptolemos JP. Prognosis of resected ampullary adenocarcinoma by preoperative serum CA19-9 levels and platelet-lymphocyte ratio. J Gastrointest Surg 2008; 12:1422-8. 8. Shimada H, Oohira G, Okazumi S, Matsubara H, Nabeya Y, Hayashi H, Takeda A, Gunji Y, Ochiai T. Thrombocytosis associated vvith poor prognosis in patients vvith esophageai carcinoma. J Am Coll Surg 2004; 198:737-41. 9. Rodriguez GC, Clarke-Pearson DL, Soper JT, Berchuck A, Synan I, Dodge RK. The negative prognostic implications of thrombocytosis in women vvith stage IB cervicai cancer. Obstet Gynecl 1994; 83:445-8. 10. Ropponen KM, Eskelinen MJ, Lipponen PK, et al. Prognostic value of tumour-infiltrating lymphocytes (TILs) in colorectal cancer. J Pathol 1997;182:318–24. 11. Donskov F. Immunomonitoring and prognostic relevance of neutrophils in clinical trials. Semin Cancer Biol 2013;23:200–7. 12. Templeton AJ, Ace O, McNamara MG, et al. Prognostic role of platelet to lymphocyte ratio in solid tumors: a systematic review and metaanalysis. Cancer Epidemiol Biomarkers Prev 2014;23:1204–12. 13. Aliustaoğlu M, Ustaalioğlu ÖBB, Bilici A, Konya V, Gücün M, Şeker M, Gümüş M. Is the complete blood count parameters predict prognosis before treatment in metastatic gastric cancer patients? Acta Oncoligica Turcica 2010; 43; 13-18. 14. Hong WS, Hong SI, Kim CM, Kang YK, Song JK, Lee MS, Lee JO, Kang TW. Differential depression of lymphocyte subsets according to stage in stomach cancer. Jpn J Clin Oncol 1991; 21:87-93. 15. Hong WS, Min Yİ, Son YS, Hong SI. Peripheral blood lymphocyte subsets in patients with stomach cancer. J Korean Med Sci 1995; 10:164-8. 16. Ikeda M, Furukavva H, Imamura H, Shimizu J, Ishida H, Masu- tani S, Tatsuta M, Satomi T. Poor prognosis associated with thrombocytosis in patients with gastric cancer. Ann Surg Oncol 2002; 9:287-91. 17. Gwak MS, Choi SJ, Kim JA, Ko JS, Kim TH, Lee SM, Park JA, Kim MH. Effects of gender on white blood cell populations and neutrophil-lymphocyte ratio following gastrectomy in patients with stomach cancer. J Korean Med Sci 2007; 22:104-8. 18. Szor DJ, Dias AR, Pereira MA, Ramos MFKP, Zilberstein B, Cecconello I, Ribeiro-Júnior U. Prognostic Role of Neutrophil/Lymphocyte Ratio in Resected Gastric Cancer: A Systematic Review and Meta-analysis. Clinics (Sao Paulo). 2018;73:e360. 19. Lian L, Xia YY, Zhou C, Shen XM, Li XL, Han SG, Zheng Y, Mao ZQ, Gong FR, Wu MY, Chen K, Tao M, Li W. Application of platelet/lymphocyte and neutrophil / lymphocyte ratios in early diagnosis and prognostic prediction in patients with resectable gastric cancer. Cancer Biomark. 2015;15(6):899-907. 20. Xin-Ji Z, Yong-Gang L, Xiao-Jun S, Xiao-Wu C, Dong Z, Da-Jian Z. The prognostic role of neutrophils to lymphocytes ratio and platelet count in gastric cancer: A meta-analysis. Int J Surg. 2015;21:84–91. 21. Sun J, Chen X, Gao P, Song Y, Huang X, Yang Y, et al. Can the Neutrophil to Lymphocyte Ratio Be Used to Determine Gastric Cancer Treatment Outcomes? A Systematic Review and Meta-Analysis. Dis Markers. 2016;2016:7862469. 22. Hsu JT, Liao CK, Le PH, Chen TH, Lin CJ, Chen JS, et al. Prognostic Value of the Preoperative Neutrophil to Lymphocyte Ratio in Resectable Gastric Cancer. Medicine (Baltimore) 2015;94:e1589. 23. Mellor KL, Powell AGMT, Lewis WG. Systematic Review and Meta-Analysis of the Prognostic Significance of Neutrophil-Lymphocyte Ratio (NLR) After R0 Gastrectomy for Cancer. J Gastrointest Cancer. 2018; 49: 237-244. 24. Zhou WW, Chu YP, An GY. Significant difference of neutrophil-lymphocyte ratio between colorectal cancer, adenomatous polyp and healthy people. Eur Rev Med Pharmacol Sci. 2017; 21: 5386-5391. 25. Palin RP, Devine AT, Hicks G, Burke D. Association of pretreatment neutrophil-lymphocyte ratio and outcome in emergency colorectal cancer care. Ann R Coll Surg Engl. 2018; 100: 308-315. 26. Silva TH, Schilithz AOC, Peres WAF, Murad LB. Neutrophil-lymphocyte ratio and nutritional status are clinically useful in predicting prognosis in colorectal cancer patients. Nutr Cancer. 2019: 1-10. 27. Eto S, Kawahara H, Matsumoto T, Hirabayashi T, Omura N, Yanaga K. Preoperative Neutrophil-Lymphocyte Ratio Is a Predictor of Bowel Obstruction Due to Colorectal Cancer Growth. Anticancer Res. 2019; 39: 3185-9. 28. Templeton AJ, Ace O, McNamara MG, Al-Mubarak M, Vera-Badillo FE, Hermanns T, Seruga B, Ocaña A, Tannock IF, Amir E. Prognostic role of platelet to lymphocyte ratio in solid tumors: a systematic review and metaanalysis. Cancer Epidemiol Biomark Prev. 2014;23:1204–12. 29. Lu C, Gao P, Yang Y, Chen X, Wang L, Yu D, Song Y, Xu Q, Wang Z. Prognostic evaluation of platelet to lymphocyte ratio in patients with colorectal cancer. Oncotarget. 2017;8:86287–95. 30. He W, Yin C, Guo G, Jiang C, Wang F, Qiu H, Chen X, Rong R, Zhang B, Xia L. Initial neutrophil lymphocyte ratio is superior to platelet lymphocyte ratio as an adverse prognostic and predictive factor in metastatic colorectal cancer. Med Oncol. 2013; 30: 439. 31. Choi WJ, Cleghorn MC, Jiang H, Jackson TD, Okrainec A, Quereshy FA. Preoperative neutrophil-to-lymphocyte ratio is a better prognostic serum biomarker than platelet-to-lymphocyte ratio in patients undergoing resection for nonmetastatic colorectal cancer. Ann Surg Oncol. 2015; 22 Suppl 3:S603-13. 32. Li ZM, Peng YF, Du CZ, Gu J. Colon cancer with unresectable synchronous metastases: the AAAP scoring system for predicting the outcome after primary tumour resection. Colorectal Dis. 2016; 18: 255-63. 33. Son HJ, Park JW, Chang HJ, Kim DY, Kim BC, Kim SY, Park SC, Choi HS, Oh JH. Preoperative plasma hyperfibrinogenemia is predictive of poor prognosis in patients with nonmetastatic colon cancer. Ann Surg Oncol. 2013; 20: 2908-13. 34. Ying HQ, Deng QW, He BS, Pan YQ, Wang F, Sun HL, Chen J, Liu X, Wang SK. The prognostic value of preoperative NLR, d-NLR, PLR and LMR for predicting clinical outcome in surgical colorectal cancer patients. Med Oncol. 2014; 31: 305. 35. Azab B, Mohammad F, Shah N, Vonfrolio S, Lu W, Kedia S, Bloom SW The value of the pretreatment neutrophil lymphocyte ratio vs. platelet lymphocyte ratio in predicting the long-term survival in colorectal cancer. Cancer Biomark. 2014; 14: 303-12. 36. Choi WJ, Cleghorn MC, Jiang H, Jackson TD, Okrainec A, Quereshy FA. Preoperative Neutrophil-to-Lymphocyte Ratio is a Better Prognostic Serum Biomarker than Platelet-to-Lymphocyte Ratio in Patients Undergoing Resection for Nonmetastatic Colorectal Cancer. Ann Surg Oncol. 2015; 22 Suppl 3: S603-13. 37. Ying HQ, Deng QW, He BS, Pan YQ, Wang F, Sun HL, Chen J, Liu X, Wang SK. The prognostic value of preoperative NLR, d-NLR, PLR and LMR for predicting clinical outcome in surgical colorectal cancer patients. Med Oncol. 2014; 31: 305. 38. Huang XZ, Chen WJ, Zhang X, Wu CC, Zhang CY, Sun SS, Wu J. An Elevated Platelet-to-Lymphocyte Ratio Predicts Poor Prognosis and Clinicopathological Characteristics in Patients with Colorectal Cancer: A Meta-Analysis. Dis Markers. 2017; 2017: 1053125. Ayrıntılar Birincil Dil en Konular Cerrahi Bölüm Orjinal Makale Yazarlar Orcid: 0000-0003-4394-3976Yazar: Berrin PAPİLA KUNDAKTEPE (Sorumlu Yazar) Kurum: İSTANBUL ÜNİVERSİTESİ - CERRAHPAŞAÜlke: Turkey Tarihler Yayımlanma Tarihi : 31 Ağustos 2020 Kaynak Göster Bibtex @araştırma makalesi { acem703750, journal = {Archives of Clinical and Experimental Medicine}, issn = {}, eissn = {2564-6567}, address = {hırkai şerif mah. keçeci çeşmesi sok. doktorlar sitesi b blok 6/7 Fatih İstanbul Türkiye}, publisher = {Mustafa HASBAHÇECİ}, year = {2020}, volume = {5}, pages = {58 - 63}, doi = {10.25000/acem.703750}, title = {The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer}, key = {cite}, author = {Papi̇la Kundaktepe, Berrin} } APA Papi̇la Kundaktepe, B . (2020). The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer . Archives of Clinical and Experimental Medicine , 5 (2) , 58-63 . DOI: 10.25000/acem.703750 MLA Papi̇la Kundaktepe, B . "The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer" . Archives of Clinical and Experimental Medicine 5 (2020 ): 58-63 Chicago Papi̇la Kundaktepe, B . "The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer". Archives of Clinical and Experimental Medicine 5 (2020 ): 58-63 RIS TY - JOUR T1 - The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer AU - Berrin Papi̇la Kundaktepe Y1 - 2020 PY - 2020 N1 - doi: 10.25000/acem.703750 DO - 10.25000/acem.703750 T2 - Archives of Clinical and Experimental Medicine JF - Journal JO - JOR SP - 58 EP - 63 VL - 5 IS - 2 SN - -2564-6567 M3 - doi: 10.25000/acem.703750 UR - https://doi.org/10.25000/acem.703750 Y2 - 2020 ER - EndNote %0 Archives of Clinical and Experimental Medicine The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer %A Berrin Papi̇la Kundaktepe %T The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer %D 2020 %J Archives of Clinical and Experimental Medicine %P -2564-6567 %V 5 %N 2 %R doi: 10.25000/acem.703750 %U 10.25000/acem.703750 ISNAD Papi̇la Kundaktepe, Berrin . "The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer". Archives of Clinical and Experimental Medicine 5 / 2 (Ağustos 2020): 58-63 . https://doi.org/10.25000/acem.703750 AMA Papi̇la Kundaktepe B . The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer. ACEM. 2020; 5(2): 58-63. Vancouver Papi̇la Kundaktepe B . The prognostic value of preoperative neutrophil -to- lymphocyte and platelet-to-lymphocyte ratios in patients with gastric and colorectal cancer. Archives of Clinical and Experimental Medicine. 2020; 5(2): 58-63. Tam Metin ( )

Tr en Amaç: Bu çalışmada akut karbon monoksit (CO) zehirlenmesi tanısı konulan hastaların demografik ve klinik özellikleri ile Glasgow Koma Skoru (GKS) 15’in altında olan hastaların manyetik rezonans görüntüleme (MRG)’de tespit edilen serebral lezyonları tanımlamayı amaçladık. Gereç ve Yöntem: 327 hasta yaş, cinsiyet, CO zehirlenme nedenleri, klinik belirtileri, nörolojik bulguları, GKS’ları, karboksihemoglobin (COHb), serum pH, laktat, kreatin kinaz (CK), kreatini kinaz, miyokardiyal band (CK-MB), troponin-I düzeyleri ile beyin MRG bulguları ve mortalite durumları açısından retrospektif olarak değerlendirildi. Bulgular: Çalışmamızda hastaların yaş ortancası 31.5 yıl (IQR=19.5 yıl) olup, hastaların %72.2’si kadındı. Hastaların 34 (%10.4)’ünde nörolojik bulgular saptandı Nörolojik bulgusu olan hastaların dispne sıklığı anlamlı olarak yüksekti (p0,05). Nörolojik bulgusu olan hastaların, takip süresi anlamlı olarak uzun olduğu, daha sıklıkla hiperbarik oksijen tedavisi aldığı saptandı (pObjective: We aim to evaluate the demographic and clinical characteristics of patients with acute carbon monoxide (CO) poisoning, who had a Glasgow Coma Score (GCS) below 15, and who had cerebral lesions detected in magnetic resonance imaging (MRI). Methods: The age, gender, causes of CO intoxication, clinical signs, neurological findings, GCS, blood carboxyhemoglobin level (COHb), serum pH, lactate, creatine kinase (CK), creatinine kinase-myocardial band MB (CK-MB), troponin-I level, brain MRI findings, treatment, and mortality status of 327 patients were evaluated retrospectively. Results: The median age of patients was 31.5 years (IQR=19.5 years), 72.2% of the patients were women. Neurological findings were detected in 34 (10.4%) of the patients. The frequency of dyspnea was significantly higher in patients with neurological findings (p0.05). Patients with neurological findings were found to have a significantly longer follow-up period, more frequently received hyperbaric oxygen therapy (p Anahtar Kelimeler tr en Karboksihemoglobin, Acil servis, Manyetik rezonans görüntüleme, Mortalite Carboxyhemoglobin, Emergency department, Magnetic resonance imaging, Mortality Kaynakça 1. Yildiz MN, Eroglu SE, Ozen C, Yildiz HA, Sektioglu BK, Alkan C. Analysis of the effects of COHb, lactate, and troponin levels on the clinical process and outcome in patients who were admitted to the emergency service due to carbon monoxide poisoning. North Clin Istanb. 2019;3(2):141–5. doi: 10.14744/nci.2018.88709. 2. Lo C-P, Chen S-Y, Lee K-W, Chen W-L, Chen C-Y, Hsueh C-J, et al. Brain injury after acute carbon monoxide poisoning: early and late complications. AJR Am J Roentgenol. 2007;189(4):W205-11. doi: 10.2214/AJR.07.2425. 3. Mukhopadhyay S, Hirsch A, Etienne S, Melnikova N, Wu J, Sircar K, Orr M. Surveillance of carbon monoxide-related incidents - Implications for prevention of related illnesses and injuries, 2005-2014. Am J Emerg Med. 2018;36(10):1837-44. doi: 10.1016/j.ajem.2018.02.011. 4. Rose JJ, Wang L, Xu Q, McTiernan CF, Shiva S, Tejero J, et al. Carbon monoxide poisoning: pathogenesis, management, and future directions of therapy. Am J Respir Crit Care Med. 2017;195(5):596-606. doi: 10.1164/rccm.201606-1275CI. 5. Kim H, Choi S, Park E, Yoon E, Min Y, Lampotang S. Serum markers and development of delayed neuropsychological sequelae after acute carbon monoxide poisoning: anion gap, lactate, osmolarity, S100B protein, and interleukin-6. Clin Exp Emerg Med. 2018;5(3):185-191. doi:10.15441/ceem.17.217. 6. Chang YC, Lee HY, Huang JL, Chiu CH, Chen CL, Wu CT. Risk Factors and Outcome Analysis in Children with Carbon Monoxide Poisoning. Pediatr Neonatol. 2017;58(2):171-7. doi: 10.1016/j.pedneo.2016.03.007. 7. Kim YJ, Sohn CH, Seo DW, Oh BJ, Lim KS, Kim WY. Clinical predictors of acute brain injury in carbon monoxide poisoning patients with altered mental status at admission to emergency department. Acad Emerg Med. 2019;26(1):60-7. doi: 10.1111/acem.13510. 8. Jeon S-B, Sohn CH, Seo D-W, Oh BJ, Lim KS, Kang D-W, et al. Acute brain lesions on magnetic resonance imaging and delayed neurological sequelae in carbon monoxide poisoning. JAMA Neurol. 2018;75(4):436-43. doi: 10.1001/jamaneurol.2017.4618. 9. Bleecker ML. Carbon monoxide intoxication. Chapter 12 In: Handb Clin Neurol. 131: Elsevier; 2015;131: 191-203. doi: 10.1016/B978-0-444-62627-1.00024-X. 10. Pepe G, Castelli M, Nazerian P, Vanni S, Del Panta M, Gambassi F, et al. Delayed neuropsychological sequelae after carbon monoxide poisoning: predictive risk factors in the Emergency Department. A retrospective study. Scand J Trauma Resusc Emerg Med. 2011;19:16. doi: 10.1186/1757-7241-19-16. 11. Thom SR, Taber RL, Mendiguren, II, Clark JM, Hardy KR, Fisher AB. Delayed neuropsychologic sequelae after carbon monoxide poisoning: prevention by treatment with hyperbaric oxygen. Ann Emerg Med. 1995;25(4):474-80. doi: 10.1016/s0196-0644(95)70261-x. 12. Kim Y, Cha Y, Kim M, Kim H, Lee Y, Youk H, et al. The usefulness of diffusion-weighted magnetic resonance imaging performed in the acute phase as an early predictor of delayed neuropsychiatric sequelae in acute carbon monoxide poisoning. Hum Exp Toxicol. 2018;37(6):587-95. doi: 10.1177/0960327117722821. 13. O'donnell P, Buxton P, Pitkin A, Jarvis LJ. The magnetic resonance imaging appearances of the brain in acute carbon monoxide poisoning. Clin Radiol. 2000;55(4):273-80. doi: 10.1053/crad.1999.0369. 14. Kaya H, Coskun A, Beton O, Kurt R, Yildirim M, Gul I. A cost effective parameter for predicting the troponin elevation in patients with carbon monoxide poisoning: red cell distribution width. Eur Rev Med Pharmacol Sci. 2016;20(13):2891-8. 15. Stearns D, Sircar K. National unintentional carbon monoxide poisoning estimates using hospitalization and emergency department data. Am. J. Emerg. 2019;37(3):421-6. doi: 10.1016/j.ajem.2018.06.002. 16. Hassan, OA, Abdelaleem, SA, Hamdy, L. A prospective comparative study between three chemical markers for predicting delayed neurological sequelae in patients with acute carbon monoxide poisoning of poison control center in Minia University Hospital. Ain-Shams J Forensic Med Clin Toxicol 2018; 31: 23–32. doi: 10.21608/AJFM.2018.15874. 17. Genç S, Aygün D. Karbonmonoksit Zehirlenmesinde Karboksihemoglobin Düzeyi, Zehirlenmenin Şiddeti ve Mini Mental Durum Testi Skalası Arasındaki İlişki. Turk J Emerg Med. 2013;13(1): 25-32. doi: 10.5505/1304.7361.2013.36002. 18. Sohn CH, Huh JW, Seo DW, Oh BJ, Lim KS, Kim WY. Aspiration pneumonia in carbon monoxide poisoning patients with loss of consciousness: prevalence, outcomes, and risk factors. Am J Med. 2017;130(12):1465. e21-. e26. doi: 10.1016/j.amjmed.2017.06.038. 19. Sokal JA, Kralkowska E. The relationship between exposure duration, carboxyhemoglobin, blood glucose, pyruvate and lactate and the severity of intoxication in 39 cases of acute carbon monoxide poisoning in man. Archives of toxicology. 1985;57(3):196-9. doi: 10.1007/bf00290887. 20. Keles A, Demircan A, Kurtoglu G. Carbon monoxide poisoning: how many patients do we miss?. Eur J Emerg Med. 2008;15(3):154-7. doi: 10.1097/MEJ.0b013e3282efd519. 21. Besli GE, Ergüven M, Karadogan M, Yilmaz Ö. Carbon Monoxide Poisoning in Children. Eurasian J Emerg Med 2010;9:26–30. doi: 10.4170/JAEM.2009.19480. 22. Benaissa ML, Mégarbane B, Borron SW, Baud FJ. Is elevated plasma lactate a useful marker in the evaluation of pure carbon monoxide poisoning? Intensive Care Med. 2003;29(8):1372-5. doi: 10.1007/s00134-003-1866-0. 23. Chu K, Jung K-H, Kim H-J, Jeong S-W, Kang D-W, Roh J-K. Diffusion-weighted MRI and 99mTc-HMPAO SPECT in delayed relapsing type of carbon monoxide poisoning: evidence of delayed cytotoxic edema. Eur Neurol. 2004;51(2):98-103. doi: 10.1159/000076536. 24. Thom SR, Taber RL, Mendiguren II, Clark JM, Hardy KR, Fisher AB. Delayed neuropsychologic sequelae after carbon monoxide poisoning: prevention by treatment with hyperbaric oxygen. Ann Emerg Med. 1995;25(4):474-80. doi: 10.1016/s0196-0644(95)70261-x. 25. Ducassé JL, Celsis P, Marc-Vergnes JP. Non-comatose patients with acute carbon monoxide poisoning: hyperbaric or normobaric oxygenation?. Undersea Hyperb Med. 1995, 22(1):9-15. 26. Moon RE, DeLong E. Hyperbaric oxygen for carbon monoxide poisoning. Med J Aust. 1999 Mar 1;170(5):197-9. Ayrıntılar Birincil Dil en Konular Sağlık Bilimleri ve Hizmetleri Yazarlar Orcid: 0000-0003-2751-0046Yazar: Nezih KAVAK (Sorumlu Yazar) Kurum: University of Health Sciences Dışkapi Yıldırım Beyazıt Training and Research Hospital, Emergency Department, Ankara, Turkey.Ülke: Turkey Orcid: 0000-0003-1379-7832Yazar: Burcu DOĞAN Kurum: Hitit University Erol Olcok Training and Research Hospital, Emergency Department, Çorum, Turkey.Ülke: Turkey Orcid: 0000-0003-4099-572XYazar: Hasan SULTANOĞLU Kurum: Düzce University Medical Faculty, Emergency Department, Düzce, Turkey.Ülke: Turkey Orcid: 0000-0001-9782-0029Yazar: Rasime Pelin KAVAK Kurum: University of Health Sciences Dışkapı Yıldırım Beyazıt Training and Research Hospital, Radiology Department, Ankara, Turkey.Ülke: Turkey Orcid: 0000-0002-7388-2871Yazar: Meltem ÖZDEMİR Kurum: University of Health Sciences Dışkapı Yıldırım Beyazıt Training and Research Hospital, Radiology Department, Ankara, Turkey.Ülke: Turkey Tarihler Yayımlanma Tarihi : 9 Ekim 2020 Kaynak Göster Bibtex @araştırma makalesi { ktd735274, journal = {Konuralp Medical Journal}, issn = {1309-3878}, eissn = {1309-3878}, address = {}, publisher = {Düzce Üniversitesi}, year = {}, pages = { - }, doi = {10.18521/ktd.735274}, title = {Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning}, key = {cite}, author = {Kavak, Nezih and Doğan, Burcu and Sultanoğlu, Hasan and Kavak, Rasime Pelin and Özdemi̇r, Meltem} } APA Kavak, N , Doğan, B , Sultanoğlu, H , Kavak, R , Özdemi̇r, M . (). Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning . Konuralp Medical Journal , , . DOI: 10.18521/ktd.735274 MLA Kavak, N , Doğan, B , Sultanoğlu, H , Kavak, R , Özdemi̇r, M . "Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning" . Konuralp Medical Journal ( ): Chicago Kavak, N , Doğan, B , Sultanoğlu, H , Kavak, R , Özdemi̇r, M . "Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning". Konuralp Medical Journal ( ): RIS TY - JOUR T1 - Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning AU - Nezih Kavak , Burcu Doğan , Hasan Sultanoğlu , Rasime Pelin Kavak , Meltem Özdemi̇r Y1 - 2020 PY - 2020 N1 - doi: 10.18521/ktd.735274 DO - 10.18521/ktd.735274 T2 - Konuralp Medical Journal JF - Journal JO - JOR SP - EP - SN - 1309-3878-1309-3878 M3 - doi: 10.18521/ktd.735274 UR - https://doi.org/10.18521/ktd.735274 Y2 - 2020 ER - EndNote %0 Konuralp Tıp Dergisi Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning %A Nezih Kavak , Burcu Doğan , Hasan Sultanoğlu , Rasime Pelin Kavak , Meltem Özdemi̇r %T Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning %D 2020 %J Konuralp Medical Journal %P 1309-3878-1309-3878 %R doi: 10.18521/ktd.735274 %U 10.18521/ktd.735274 ISNAD Kavak, Nezih , Doğan, Burcu , Sultanoğlu, Hasan , Kavak, Rasime Pelin , Özdemi̇r, Meltem . "Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning". Konuralp Medical Journal - . https://doi.org/10.18521/ktd.735274 AMA Kavak N , Doğan B , Sultanoğlu H , Kavak R , Özdemi̇r M . Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning. Konuralp Medical Journal. -. Vancouver Kavak N , Doğan B , Sultanoğlu H , Kavak R , Özdemi̇r M . Clinical and Magnetic Resonance Imaging Findings of Patients with Acute Carbon Monoxide Poisoning. Konuralp Medical Journal. -.

Protection of health care professionals is of great importance and concern during the coronavirus disease 2019 (COVID-19) pandemic. Previous papers have given recommendations of protection of medical staff while working in hospitals and clinics facing the new disease (1–4), but what was recommended after they left work and returned to their residences was barely mentioned. Actually, it is crucial for the protection for medical staff themselves, their families, and also public health. We hereby share our experience about the designed after-work protocols that protected 482 medical staff that were sent from Changsha to Wuhan and to a locally designated hospital to support the medical system from the highly contagious COVID-19. In China, as close contacts of the suspicious or confirmed COVID-19 patients, most of the medical staff that worked in the COVID-19 clinics/wards lived in designated hotels or temporary residences so that necessary self-quarantine was guaranteed and the superfluous risk of transmission of infection was minimized as much as possible. We believe this article about the protocols we designed and strictly followed based on aseptic principles and quarantine regulations would also be of some help for those medical professionals who return home after work. An infection control area was set immediately after the entrance of the residences, divided into the contaminated area, buffer area, and clean area (Figures 1A,B). Figure 1. (A) 2-D floor plan and the area setting. (I) Contaminated zone; (II) Buffer zone; (III) Clean zone. (B) 3-D floor plan and the area setting. I. Contaminated zone: (a) Coat hangers, (b) shoe box with a disposable plastic bag with chlorine-containing disinfectant, (c) garbage bags and the garbage can, (d) a small shelf; II. Buffer zone: (e) bathroom, (f) shoes for buffer zone, (g) garbage can; III. Clean zone: (i) Indoor shoes; (C) In the contaminated zone a shelf was set for: (1, 2) hand disinfection solution, (3) chlorine-containing disinfectant, (4) alcoholic sprinkling can, (5) cotton swabs and gauze, (6) iodine, (7) gloves, (8) alcohol pads, and (9) tissue. First area after the entry. A shoe box with a disposable plastic bag with chlorine-containing disinfectant was set there to get the shoe soles sterilized. The plastic bag was replaced daily by the resident. It is extremely recommended considering that our colleagues in Wuhan found that that about half of healthcare professionals working in intensive care units carried coronavirus on the soles of their shoes. (5) Coat hangers were set behind the door for outside clothes. A shelf was set for a hand disinfection solution, alcoholic sprinkling can, alcohol pads, tissues, cotton swabs, gauze, gloves, garbage bags, and a garbage can (Figure 1C). The showers and bathrooms; for shower slippers, toiletries, alcoholic pads, Q-tips, and one trash can. The rest of the indoor living area. Indoor shoes and clothes were required. Step 1: Enter the residence (hotel rooms or home), take off and put the shoes in the shoe box for sterilization; hand hygiene; use alcoholic pads to disinfect the smart phone and spectacle frames; take off and disinfect the outside clothes with the sprinkling can and place them on the hanger. Step 2: Enter the bathroom, wash hands again; take a shower; use alcoholic pads for auricles and ala nasi. Step 3: Put on indoor clothes and shoes and get into the clean area. We strongly recommend the daily wear of masks for medical staff. We do believe it is of great importance for public health. DO NOT try to sterilize the facial masks with alcohol even if replacement is not optional. Alcohol would damage the waterproof layer of facial masks and impair the protection efficacy. When repeated use of facial masks is inevitable, we recommend processing the facial mask with the heat of a hairdryer for 30 min to hopefully deactivate the viruses (4, 6). Indoor garbage was put in sealed garbage bags by the residents themselves. Bags were placed outside the door or designated sites and specially labeled as a reminder for special handling by the staff. Professionally trained workers of the hotels would collect the labeled bags daily. Going out of the rooms to get food and living supplies and re-entry are somewhat inevitable. Follow the protocols and skip Step 2 if clinics/wards are not where you come back from. As of this article's writing, no confirmed case of COVID-19 has been reported among our medical staff; 482 medical staff were tested negative with CT scan, swab-gold pharyngeal, and serology testing. Considering the difficulty in identifying asymptomatic carriers, we believe it is crucial to pay attention to all the details in self-protection. After all, health care professionals are the most valuable resources in the global pandemic. Sincerely, we hope our experience will be of help to medical staff worldwide. CC provide the concepts and ideas of the article. XH and JL drafted the paper. HL and CC performed a critical revision of the first draft and the final editing of the manuscript. All authors have critically revised the manuscript for important intellectual content and gave final approval for the version to be published. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. 1. Cao Y, Li Q, Chen J, Guo X, Miao C, Yang H, et al. Hospital Emergency Management Plan During the COVID-19 Epidemic. Acad Emerg Med. (2020) 27:309–11. doi: 10.1111/acem.13951 PubMed Abstract | CrossRef Full Text | Google Scholar 2. Huang L, Lin G, Tang L, Yu L, Zhou Z. Special attention to nurses' protection during the COVID-19 epidemic. Critical Care. (2020) 24:120. doi: 10.1186/s13054-020-2841-7 PubMed Abstract | CrossRef Full Text | Google Scholar 3. Zhang X, Shao F, Lan X. Suggestions for safety and protection control in Department of Nuclear Medicine during the outbreak of COVID-19. Eur J Nucl Med Mol Imaging. (2020) 47:1632–33. doi: 10.1007/s00259-020-04779-x PubMed Abstract | CrossRef Full Text | Google Scholar 4. Livingston E, Desai A, Berkwits M. Sourcing personal protective equipment during the COVID-19 pandemic. JAMA. (2020) 323:1912–14. doi: 10.1001/jama.2020.5317 PubMed Abstract | CrossRef Full Text | Google Scholar 5. Guo ZD, Wang ZY, Zhang SF, Li X, Li L, Li C, et al. Aerosol and surface distribution of severe acute respiratory syndrome Coronavirus 2 in Hospital Wards, Wuhan, China, 2020. Emerg Infect Dis. (2020) 26:1583–91. doi: 10.3201/eid2607.200885 PubMed Abstract | CrossRef Full Text 6. Song WH, Pan B, Kan HD, Xu YY, Yi ZG. Evaluation of heat inactivation of virus contamination on medical mask[J]. J Microbes Infect. (2020) 15:31–5. doi: 10.3969/j.issn.1673-6184.2020.01.006 CrossRef Full Text Keywords: coronavirus disease 2019, self-quarantine, facial masks, global pandemic, medical staffs Citation: Huang X, Li J, Liang H and Chen C (2020) How to Protect Medical Staff in the COVID-19 Battlefield After Work. Front. Public Health 8:421. doi: 10.3389/fpubh.2020.00421 Received: 25 May 2020; Accepted: 13 July 2020; Published: 06 August 2020. Edited by: Reviewed by: Copyright © 2020 Huang, Li, Liang and Chen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Chen Chen, [email protected] ^†These authors have contributed equally to this work

The United States, with over 11 million cases and ~250,000 deaths (1), has become the epicenter of the COVID-19 worldwide pandemic since the first case was identified in Washington State on January 19, 2020. In New York City the first case of community acquired COVID-19 was identified on March 1, 2020 and the number of known cases increased rapidly making the city the epicenter of COVID-19 in the United States. Public hospitals became deluged with patients as the communities they serve, urban poor and minority, were disproportionately affected by the disease. COVID-19 often affects the nervous system with both central and peripheral sequalae, neurology services had to adapt to a new landscape (2–6). This paper will report on the process changes for the neurology service, in particular for stroke and electroencephalography (EEG) services, at King County Hospital Center (KCHC), a 637 bed, public, university-affiliated, teaching hospital in central Brooklyn, New York, which serves a predominantly African American community. Implementing those changes resulted in maintaining our pre-COVID structure and quality of care despite the workflow, economic, and technical challenges induced by the virus. The first known COVID-19 patient was admitted to KCHC on March 13, 2020, almost 2 weeks after the first known case of COVID-19 was identified in New York City. The number of cases rapidly increased first in Manhattan and then in Brooklyn before in Queens and then in the Bronx. In March and April as case numbers surged at KCHC, strategies to protect patients and staff were developed and implemented rapidly as we learned first-hand about the disease. Initially, COVID-19 was thought to be a respiratory disease. However, in the first few days of the surge of patients, multiple Neurology and Emergency Medicine personnel were exposed to COVID-19 patients who presented with strokes but without respiratory complaints. The Neurology Service responded by promptly instituting a policy that full personal protective equipment (PPE) including N95 masks and face shields be used for performing stroke codes, adapting procedures for performing neurologic examinations, and changing the workflow for EEG. We also reorganized our services and participated in many facets of the hospital-wide COVID-19 response As was the case in many other hospitals when COVID-19 arrived, our Neurology Department made staffing changes to support the COVID-19 effort. We disbanded our Neuro Critical Care Service and sent the attendings into the Intensive Care Unit (ICU) attending pool as the hospital expanded its ICU bed capacity from 40 to 200 ICU beds. The Neurology Consultation Service provided neurology guidance on critically ill patients with neurologic conditions. Our Neuro Critical Care attendings graciously answered our questions on difficult to manage patients. Our current stroke fellow is also an Emergency Medicine attending and he put his fellowship on hold and went full time to the Emergency Department (ED) during the peak of the crisis. The inpatient Neurology Service expanded to become a combined Neurology-COVID service caring for patients with neurological conditions, COVID-19, or both. We received training on the evolving management of COVID-19 from Infectious Disease and ICU attendings. We also held a journal club on the neurologic manifestations of COVID-19 and regularly emailed pertinent articles to the entire Neurology faculty and all trainees. The Pulmonary Service consulted regularly on our patients on mechanical ventilation and BIPAP. The infectious disease attendings came by on a daily basis to advise us on both the management of COVID-19 and multiple other medical issues. Our Adult Neurology residents and attendings also rotated onto the Medicine services which were almost all COVID-19 wards. Of the two approaches, expanding the scope of the Neurology-COVID-Medicine service worked better. We maintained our pre-COVID structure and were better able to maintain the morale of our teams. On the outpatient side, we rapidly transitioned from in-person visits to telephone visits (televisits) and eventually our Stroke Clinic instituted video visits. Electromyography and outpatient EEG studies were suspended until the surge passed. Our Pediatric Neurology fellows performed nasopharyngeal swabs for outpatient and employee testing. Our Adult and Pediatric Neurology attendings helped out Employee Health with the phone calls to quarantined staff. Our Pediatric Neurology fellows also rounded with the ICU teams and served as the liaison with the families who were not allowed to visit their loved ones. Our Stroke Nurse Practitioner became the PPE trainer for stroke codes but also for trauma codes. She quickly trained all of the staff on both Trauma and Neurology in proper PPE donning, use, and doffing. In addition, she developed Stroke code kits comprised of N-95 masks, face shields, gowns, bonnets, and gloves, so the responder had a pre-assembled set of PPE and could rapidly prepare to safely answer a stroke code. We also analyzed and adapted the workflow of the stroke code and neuro exam. Prior to the pandemic, we used laminated pocket cards for aphasia testing. During the pandemic we blew up the pocket cards used for aphasia testing onto 8.5 × 11 sheets of paper that were discarded after each use. Pen lights were encased in sealed plastic bags to facilitate repeated cleanings with gel before and after each patient encounter. Fundoscopic examinations were halted due to the prolonged close interaction. Pupil examinations and cranial nerve examinations are also performed in close proximity to the patient's face, so we required N-95 mask and face shield use for all patient encounters in order to perform these procedures safely. Throughout the hospital patients were cohorted into “hot zones” for COVID-19 positive patients and “cold zones” for COVID-19 negative ones. As much as possible hot and cold zones were separate wards. Patients under investigation for COVID-19 (PUIs) were housed in single rooms in hot zones until their status could be determined for an appropriate ward allocation. However, due to the specialized nature of our Stroke Unit, the Neurology unit became a “mixed zone” unit for much of the surge. Attending rounds started with the COVID-19 negative patients, then PUIs, and finished with COVID-positive patients. Rounds were asynchronous with only the attending and the resident caring for the patient entering the patient's room. The Stroke Service developed a stroke cart with interactive video that could be monitored remotely so that when the attending and resident went into the patient's room to examine the patient, the rest of the team could view the interaction and observe social distancing. In particular, this enabled the on-call residents to remotely view the patient's neurologic examination and maintain the quality of care. Unlike other centers, KCHC has seen an increase in both ischemic and hemorrhagic stroke volumes during the month of March of the pandemic in comparison to the same period in 2019 (Figure 1). In the earliest phase of the surge of COVID-19 cases, all the stroke patients were COVID-19 positive. As the pandemic progressed the number of stroke cases decreased and then returned to pre-COVID levels as the patients became COVID negative. Figure 1. March through June Stroke Volumes (2019 vs 2020). Aside from the new PPE requirements and shortened more distant neurological examinations, stroke codes were minimally affected by COVID-19. We had the same indications for tPA administration and used the same algorithms for thrombectomies. At the surge's peak, when ICU beds were tight and we were able to provide a step-down level of care on our Neurology unit, we modified our tPA administration pathway using the Safety Trial of Low-Intensity Monitoring After Thrombolysis (OPTIMIST) trial as a basis (7). The streamlined OPTIMIST protocol was chosen given that it limits the frequency of patient interactions, while still maintaining patient safety. We administered tPA in the ED and performed the initial 2 h of neuro checks every 15 min as usual. At that point, the patient was transferred to the Neurology unit where neuro checks were performed every hour for 8 h. A non-contrast computerized tomography of the head was performed and, if no hemorrhage was demonstrated, the patient then received neuro checks every 4 h to complete 24 h of post-tPA monitoring. We did not see an increase in complications using this modified tPA administration pathway. After stroke codes, performing EEG was the next highest risk procedure due to the prolonged interaction time and close proximity to the patient's head. The American Clinical Neurophyisology Society recommendations for minimizing equipment contamination and the amount of time the EEG tech needs to stay in the room were followed (8). They stated that efforts should be made to limit technician exposure to potentially infectious patients; to consider rapid application EEG with disposable, single use caps/ templates; use of antiseptic wipes to clean all surfaces of the equipment that has entered any COVID+/PUI patient room; consider using one use plastic covers to shield EEG equipment in COVID+/PUI rooms; consider keeping the machine outside the patient's room (via long wiring). Our EEG technicians wore the same PPE as used for stroke codes and we modified the EEG procedures to minimize patient interactions in several ways. We used the novel Bio-Signal group system of disposable electrode strips. We chose this system because it allows for good electrode coverage of most of the brain with 16 electrodes (as opposed to 21 with the traditional 10–20 system) and is rapidly applied (9). The average traditional electrode setup time is 27 min. In addition to deployment time, the tech would normally have to reenter the patient's room to check signal quality at least 3 times for a 24-h study. After training, our EEG technicians were able to apply the novel, rapidly deployable system in 3 min. In addition, we configured the EEG acquisition system to allow the EEG to display on a laptop located outside the patient's room so that the EEG technician could leave the patient's room and still monitor the EEG quality. The studies were uploaded to a server via a sender application on the laptop allowing the neurologists to interpret the studies remotely. From March 1, 2019 through June 5, 2019, 235 inpatient EEG studies were performed of which 200 were routine and 35 were continuous and for the same time period in 2020, a total of 225 EEG studies were performed (4% decrease), of which 178 were routine (11% decrease) and 47 were continuous (34% increase) (Figure 2). This increase in continuous EEG volumes is in contrast to other institutions which witnessed a dramatic decrease (10). Figure 2. March through June EEG Volumes (2019 vs 2020). The COVID-19 pandemic hit Brooklyn and Kings County Hospital Center hard as it did elsewhere and is continuing to do so today. As a public hospital we made do with limited financial resources and leveraged technology and the resourcefulness of our staff. The Neurology Service attending physicians, residents and technicians altered their daily processes to adapt to the overwhelming nature of this virus. Adhering to strict Infection Control protocols, receiving a crash course in medical management of the COVID-19 patient, modifying our stroke code and examination protocols, and employing advanced technology for the performance of EEG allowed the service to perform its tasks safely and efficiently and to maintain quality of care. HV and SA contributed to the study design, data analysis, and editing. NS and SL provided editorial and have reviewed and approved the final work. All authors contributed to the article and approved the submitted version. SA reports support from Bio Signal Group. In addition, SA has a U.S. patent 13/284,886. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. 1. Coronavirus COVID-19 Global Cases by the Center for Systems Science and Engineering at Johns Hopkins University. (2020). Available online at: https://coronavirus.jhu.edu/map.html (accessed November 19, 2020). 2. Mao L, Jin H, Wang M, Wang M, Hu Y, Chen S, et al. Neurologic manifestations of hospitalized patients with coronavirus disease 2019 in Wuhan, China. JAMA Neurol. (2020) 77:683–90. doi: 10.1001/jamaneurol.2020.1127 PubMed Abstract | CrossRef Full Text | Google Scholar 3. Romero-Sánchez CM, Díaz-Maroto I, Fernández-Díaz E, Sánchez-Larsen Á, Layos-Romero A, García-García J, et al. Neurologic manifestations in hospitalized patients with COVID-19: the ALBACOVID registry. Neurology. (2020) 95:e1060–e1070. doi: 10.1212/WNL.0000000000009937 PubMed Abstract | CrossRef Full Text | Google Scholar 4. Tsvigoulis G, Palaiodimou L, Katsanos AH, Caso V, Köhrmann M, Molina C, et al. Neurological manifestations and implications of COVID-19 pandemic. Ther Adv Neurol Disord. (2020) 13:1–14. doi: 10.1177/1756286420932036 PubMed Abstract | CrossRef Full Text | Google Scholar 5. Frontera J, Savadia S, Lalchan R, Fang T, Flusty B, Millar-Vernetti P, et al. A prospective study of neurologic disorders in hospitalized COVID-19 patients in New York City. Neurology [Preprint]. (2020) 10. doi: 10.1212/WNL.0000000000010979 PubMed Abstract | CrossRef Full Text | Google Scholar 6. Divani AA, Andalib S, Biller J, Di Napoli M, Moghimi N, Rubinos CA, et al. Central nervous system manifestations associated with COVID-19. Current Neurol Neurosci Rep. (2020) 20:60. doi: 10.1007/s11910-020-01079-7 CrossRef Full Text | Google Scholar 7. Faigle R, Butler J, Carhuapoma HR, Johnson B, Zink EK, Shakes T, et al. Safety trial of low-intensity monitoring after thrombolysis: optimal post Tpa-Iv monitoring in ischemic stroke (OPTIMIST). Neurohospitalist. (2020) 10:11–15. doi: 10.1177/1941874419845229 PubMed Abstract | CrossRef Full Text | Google Scholar 8. American Clinical Neurophysiology Society (ACNS) Recommendations Technologist Safety and Staffing. (2020). Available online at: https://www.acns.org/UserFiles/file/ACNSCOVID-19Recs_TechSafetyStaffing_v1.pdf (accessed March 22, 2020). 9. Zehtabchi S, Abdel Baki SG, Omurtag A, Sinert R, Chari G, Roodsari GS, et al. Effect of micro-electroencephalogram on clinical management and outcomes of emergency department patients with altered mental status: a randomized controlled trial. Acad Emerg Med. (2014) 21:283–91. doi: 10.1111/acem.12324 CrossRef Full Text | Google Scholar 10. Sethi NK. EEG during the COVID-19 pandemic: what remains the same and what is different. Clin Neurophysiol. (2020) 131:1462. doi: 10.1016/j.clinph.2020.04.007 PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: change in process, EEG, critical care, stroke, COVID-19 Citation: Valsamis H, Sheikin N, Law S and Abdul Baki S (2021) Process Changes for Stroke Care and Electroencephalography on a Neurology Service in a Hospital at the Epicenter of the COVID-19 Pandemic. Front. Neurol. 11:605315. doi: 10.3389/fneur.2020.605315 Received: 24 October 2020; Accepted: 07 December 2020; Published: 08 January 2021. Edited by: Reviewed by: Copyright © 2021 Valsamis, Sheikin, Law and Abdul Baki. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Helen Valsamis, [email protected]

As the supply of nucleic acid detection kits for coronavirus disease 2019 (COVID-19) is gradually approaching the demand for testing those with moderate or severe symptoms, even those with mild symptoms of the common cold in some countries, research interests in scientific communities have started to shift to those unidentified COVID-19 infections presenting mild or even no symptoms (i.e., asymptomatic COVID-19 infections). The observed rates of asymptomatic COVID-19 infections have varied from 17% in a family of six to 67% in a family of three (1, 2). Although such observational studies are subject to the limited sample size and selection bias, the emerging studies estimating the rates of unidentified COVID-19 infections may be subject to more severe biases or even errors, if we do not have a deep understanding of unidentified COVID-19 infections in the context of efforts of epidemic control and prevention on the ground. For example, a recent study simulating the dynamics of coronavirus disease 2019 (COVID-19) infection during 10–23 January 2020 revealed “a very high rate of undocumented infections: 86%” (3). However, such an estimate should be treated with caution because several flaws in fundamental definitions and assumptions in that study can significantly affect the accuracy and implications of the results. A most basic flaw is that they “divided infections into two classes: (i) documented infected individuals with symptoms severe enough to be confirmed, i.e., observed infections; and (ii) undocumented infected individuals.” In this seemingly reasonable procedure, authors mixed up three concepts, i.e., undocumented, unconfirmed, and unnoticed, which has fundamentally undermined the accuracy of that study and largely accounted for why that estimate has not been validated or even approached by any observational study so far. Such flawed definitions and assumptions would also undermine the quality of many more, if not all, forthcoming scientific studies in that direction and, more importantly, mislead general readers in understanding what has happened at the beginning of the COVID-19 pandemic in other provinces than Hubei Province of China. Therefore, they deserve some factual explanations. First, the rate of “undocumented” infections is not an estimatable concept. It would have been more appropriate to estimate the rate of “unnoticed” infections (i.e., asymptomatic infections) or “unconfirmed” infections (i.e., untested infections) (4). In particular, authors have clearly explained the first class as “observed” infections, then the second class was actually, also naturally, “unobserved” infections, which should be more rigorously defined as “unnoticed” infections or, at the very least, less rigorously defined as “unnoticed” or “unconfirmed” infections. In any case, conceptually, scientifically, or literally, the second class should have been correctly defined. Failure to do so has further led to other problematic statements and assumptions in the following. Second, observed infections were equal to “documented infected individuals with symptoms severe enough to be confirmed,” which was problematic due to lack of a clear definition of “symptoms severe enough.” Such vagueness also existed in another statement that “these undocumented infections often experience mild or limited symptoms and hence go unrecognized,” where “mild” and “limited” symptoms were not clearly defined. A reasonable guess is that authors did not have sufficient knowledge of COVID-19 symptoms at the time of conducting this study, according to the entire lack of early epidemiological studies including clinical characteristics of COVID-19 patients in the reference list of that article (5–7). Defining the epidemiology of COVID-19 on the basis of a large enough sample of infected cases (8) or their spatiobehavioral characteristics (i.e., individuals' close contact with infectors for a certain amount of time) (9), and thereby understanding the characteristics of COVID-19 (i.e., elucidating what the full spectrum of disease severity is, how transmissible the virus is, who the infectors are), is a critical step prior to any reliable scientific study examining the transmission and impact of COVID-19. This is also why very few (reliable) studies, if not entirely lacking, in this direction have been conducted outside China before March 2020. Therefore, simulating the dynamics of symptomatic and asymptomatic COVID-19 infections without considering the definitions of COVID-19 symptoms has invalidated that study to some extent. Third, the statement that “these undocumented infections often experience mild or limited symptoms and hence go unrecognized” is not true in all provinces but Hubei, where most, if not all, infections presenting mild symptoms in other provinces have visited their nearby fever clinics and been tested at the first moment possible (10–12); thus, they could not have gone unrecognized. Only some of those experiencing mild or limited symptoms prior to 23 January in Hubei Province, especially in Wuhan, may not be timely tested for COVID-19, due to insufficient capacity of conducting COVID-19 nucleic acid testing at that time; even so, most infections presenting any symptom have visited their local fever clinics and been triaged for at-home isolation or in-hospital isolation and treatment (11). Therefore, “the transmission rate due to undocumented individuals” in that study, in the simplest assumption, should be different for “unconfirmed” and “unnoticed” infections rather than a constant value for both groups of infections. This mistake could simply occur because authors failed to differentiate “unconfirmed” from “unnoticed” infections among “undocumented.” The transmission rate among “unconfirmed” infections, if not zero, should be much lower than that of “unnoticed” infections, which invalidated authors' another statement that “those often experiencing mild, limited or no symptoms, depending on their contagiousness and numbers, can expose a far greater portion of the population to virus than would otherwise occur”. In addition, there have been many intrapersonal and interpersonal variations in the contagiousness over time, which could not be simply hypothesized (13). Also, the number of infections from those variable or unknown contagiousness depends heavily on the physical interaction between people, which could not be realized without the support and integration of individual-level movement trajectory (14, 15). Fourth, the statement that “these undocumented infections often experience no symptoms and hence go unrecognized” is not aligned with epidemic control and prevention efforts on the ground, and also could not be validated until blanket testing. Since the beginning of the COVID-19 outbreak, the local Centers for Disease Control and Prevention (CDC) in all Chinese provinces except Hubei have been helping infected people experiencing any symptom recall all their potential contacts, who have then been tested while experiencing no symptoms (16). Only a very small number of asymptomatic infections were detected in that way, which added little to the infected population; for example, the infection rates of close contacts of confirmed cases and asymptomatic infections were 6.30% (126 out of 2,001) and 4.11% (6/146), respectively (17). Despite the lack of an overall picture of the number and distribution of asymptomatic infections at the early stage of the epidemic, what had been done at that time for identifying asymptomatic infections in China has been considered acceptable (18). Last but not least, none of observational studies published so far have validated or even been close to the “undocumented infection rate of 86%” estimated based on those flawed definitions and assumptions. The national health commission of China published that, as of 31 March, 2020, the total number of asymptomatic COVID-19 infections was 1,541 including 205 imported cases (19). A recent observational study revealed that asymptomatic infections contributed to only <5% of the total infected population, and their contagiousness was only 1/6-1/3 of the contagiousness of confirmed infections in Ningbo, Zhejiang Province of China (17). Although the estimates may vary across Chinese cities, the Chinese CDC has confirmed that the result is in the right ballpark. After all, the observed rate of asymptomatic COVID-19 infections was just 30.8% among 565 Japanese people evacuated from Wuhan by 6 February 2020 (20). Given that blanket testing is currently not possible in most if not all countries, especially during epidemics when healthcare resources are relatively lacking, reporting unvalidated estimates of the rate of unnoticed infections may not be the optimal way in which both policy-makers and citizens should be informed of the severity of epidemics (21). Unvalidated estimates without consideration of epidemic control and prevention efforts on the ground are against the international recognition by the World Health Organization and public health scientists all over the world who have closely followed the emergence of the COVID-19 (18, 22). They could have been exploited by media to harm the scientists, public health professionals, and medical professionals who have “worked diligently and effectively to rapidly identify the pathogen behind this outbreak, put in place significant measures to reduce its impact, and share their results transparently with the global health community” (22). We suggest the involvement of local CDCs in epidemic studies for more unbiased descriptions of the facts and/or more factual assumptions. Science is important, but public health is much more complex than science. 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Public Health 9:593176. doi: 10.3389/fpubh.2021.593176 Received: 21 April 2020; Accepted: 08 March 2021; Published: 12 April 2021. Edited by: Reviewed by: Copyright © 2021 Yang, Dai, Huang and Jia. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Peng Jia, [email protected]

Since the 11th of March 2020, the 2019 coronavirus disease (COVID-19) has been declared a global pandemic by the (World Health Organization, 2020). The disease is caused by the SARS-CoV-2 and was first officially reported in Wuhan, China, in December 2019 (Zhu et al., 2020). Since then, COVID-19 has spread globally with millions of laboratory-confirmed cases and hundreds of thousands of deaths (Relief Web, 2020). So far, there is no specific treatment for the disease and many research teams are currently working on a vaccine that, optimistically, will only be available to the public in 2021. Meanwhile, the recommendation from health authorities is to adopt nonpharmaceutical interventions such as travel restrictions, school closures, social distancing, washing hands, and wearing face masks. Though these emergency measures are certainly inconvenient, social distancing has been proven historically effective in reducing and delaying infection rates and mortality on previous influenza pandemics (1918 and 2009) (Ahmed et al., 2018) while face masks minimize the risk of spreading viral particles through respiratory droplets (Leung et al., 2020). In short, the greater part of the success of mitigation strategies depends on individual responsibilities for implementing the recommended personal-level actions. Unfortunately, however, social distancing guidelines against COVID-19 have become a political hot topic and compliance has roughly been defined along ideological lines: conservatives are less probable to adhere to them than liberals (Rothgerber et al., 2020). To complicate matters, there has been a flood of conspiracy theories and false news about COVID-19. For instance, the conspiracy theory that the coronavirus is a laboratory-engineered bioweapon created by the Chinese started in January 2020 and was spread, bot-like, in Twitter by mostly right-wing and conservative profiles (Graham et al., 2020). While conspiracy theories are not the preserve of the ideological left or right, they are more common at ideological extremes and certainly strongest at the extreme right (Sutton and Douglas, 2020). The appeal of conspiracy theories is that they often serve as a “radicalizing multiplier” (Bartlett and Miller, 2010) for fringe groups while offering an easy explanation for complex issues (Marchlewska et al., 2018), thus satisfying people's need for cognitive closure (Kruglanski and Fishman, 2009). However, as seen with “the stab in the back” myth in Germany after the end of WWI, for instance, the unchallenged dissemination of conspiracy theories and false news can posit a great risk to democracy (Ardèvol-Abreu et al., 2020). Aided by the existence of modern information networks powered by the internet, coordinated disinformation campaigns disseminating conspiracy theories, false news, and health hoaxes, are more common than ever. Conspiracy theories usually have a system-justifying function of supporting the status quo by redirecting the public attention toward imaginary perils and distracting from genuine threats (Eco, 2014; Jolley et al., 2018). Health hoaxes and false news also sidetrack demands for adequate and science-backed solutions to fight the pandemic and its consequences, such as investment on vaccine development, adequate hospital infrastructure (ventilators, ICU units, etc.), and financial relief programs. Some conservative political leaders have regularly stressed the link between the adoption of social distancing guidelines with negative effects on the economy, even though there is evidence from the 1918 influenza pandemic that US cities that moved more aggressively to limit interactions among the public fared much better economically afterward than cities which were laxer (Correia et al., 2020). To justify the end of lockdowns, some have also promoted the use of unproven therapeutic methods, such as Chloroquine (CQ)/hydroxychloroquine (HCQ), to treat COVID-19 (Guzman-Prado, 2020). CQ was proposed in the 1930s as a drug to treat malaria (Peters, 1971), which is still the deadliest infectious disease in the world. HCQ was later introduced as a less toxic version of the drug and was approved to treat autoimmune diseases (Ben-Zvi et al., 2012). CQ and HCQ garnered worldwide attention as promising candidates to treat COVID-19 in early February 2020 after the publication of reports showing in vitro activity of CQ against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Wang et al., 2020). Subsequently, several randomized controlled clinical trials were initiated but none was able to prove its efficacy against COVID-19 (Recovery, 2020) and some were halted due to the possibility of harmful side effects. Meanwhile, beginning on 19 Mar 2020, President Donald Trump promoted the use of CQ/HCQ as a game-changer against COVID-19. Other conservative leaders around the world followed suit and began promoting the use of the drugs in their own countries as well. In the USA, the hype with chloroquine was short-lived due to counter-recommendations from the Food and Drug Administration (FDA) (US FDA, 2020), but in other countries, such as Brazil, it never went away due to official support for its use (See Figure 1). As shown in Figure 1 comparing the US with two other countries in the Americas (Argentina and Brazil), Google searches for CQ/HCQ spiked in response to President Trump's press meeting on 19 Mar 2020 not only in the US but in both Argentina and Brazil. Afterward, the number of searches subsided, except in Brazil, where government officials have promoted CQ/HCQ as a valid therapy against COVID-19 even though there is no availability of clinical trial data regarding its safety and efficacy (Chowdhury et al., 2020). Figure 1. The arrow marks the day that U.S. President Donald Trump held a news briefing saying the government would make the drug available “almost immediately” to treat COVID-19 (03/19/20). On 03/25/20, Brazil's President posted about the benefits of chloroquine. On 05/20/20 Brazil's Ministry of Health issued a protocol to treat COVID-19 patients with chloroquine. Even though most people obtain the news from conventional media outlets such as television and newspapers, not from social network applications or false news (Allen et al., 2020), heads of government have a bully pulpit through which they can reach a wider audience via traditional media coverage. In our polarized political times, their message is also propagated by both supporters and non-supporters in social media. Besides, the filtering technologies currently used by social media platforms facilitate the formation of psychosocial bubbles that limit the diversity of social contacts and feed the so-called digital “echo chambers” (Kaakinen et al., 2020). The main assumption of the social identity approach (SIA) is that each person not only has a distinct personal identity but also social identities that connect them to other people (Brown, 2000). According to the SIA, group memberships are important parts of a person's self-concept and shapes a person's experience of the world (Hornsey, 2008). For instance, it is known that personal ideology influences people's opinions on climate change policy (McCright and Dunlap, 2011; Fielding et al., 2020) and influence their decision to share false and misleading content, even though they generally wish to avoid spreading misinformation and are often able to tell truth from falsehood (Pennycook et al., 2019). Thus, by stressing the notion of “us” against “them,” the promoters of conspiracy theories and false news can vastly increase the chance of their message being spread. The backlash against science-based methods to fight infectious diseases is not new. For instance, anti-vaccination movements were common in the 19th century in England, the US, and Brazil (Figure 2) (Jolley and Douglas, 2014). What's new is the social environment for the propagation of contrarian views. For most online extremists, the content of the message does not matter as much as its potential to be used as a bait to amplify the visibility of a conspiracy theory to the wider public when mainstream media and prominent social media actors engage with the conspiracy theory, even critically. Even official denials and corrections can be exploited by conspiracy theorists to claim that authorities are covering up “the real truth” (Graham et al., 2020). Conspiracy theories promoted by the anti-vaccination movement have been widely circulated in social media in recent years and could even hamper the efforts to reach a larger share of the population with an eventual COVID-19 vaccine (Megget, 2020). Figure 2. A illustration from an 1894 anti-vaccination publication (The Historical Medical Library of the College of Physicians of Philadelphia). A recent study showed that misinformation about COVID-19 on Facebook is available in several languages and much of this content remains active in the platform without a warning or label, giving ample time for it to go viral (Avaaz, 2020b). In a joint statement, Facebook, Google, LinkedIn, Microsoft, Reddit, Twitter, and YouTube have vowed to work against misinformation in their platforms (Shu and Shieber, 2020). However, some observers agree that more has to be done by these companies, including correct the record on health misinformation by individually sending warnings to recipients of false news, ban repeated offenders, and change their algorithms to prevent their posts of appearing systematically on feeds (Avaaz, 2020b). Facebook's algorithm, for instance, rewards and encourages user's engagement with content that provokes strong emotions, which is usually how false information is packaged: as something novel and sensational (Avaaz, 2020a). Thus, there is a strong need for a vast campaign led by respected institutions and individuals to advise the public to be cautious with dubious claims of effective therapies for COVID-19 and other infectious diseases. A recent proposal is to implement a suite of interventions based on accuracy nudges to make people think about the accuracy of the information they want to share in social platforms (Pennycook et al., 2020). Also, factually inaccurate information disseminated in social media should be promptly labeled and/or removed by social media outlets. Unfortunately, only tagging such stories as inaccurate, as done by Twitter, for instance, does not seem to be an effective solution to this problem (Pennycook et al., 2018). However, to preserve fundamental free-speech rights, moderation decisions should be carried with the utmost transparency by non-governmental oversight boards selected to represent society's diversity. Moderating decisions should be explained in the most user-friendly way to the public. Although there is a strong debate on the effectiveness of corrective measures (Jerit and Zhao, 2020), recent research shows that repeated exposure to correct information contributes to repair the damage of viral misinformation spread in the realm of social media (Carnahan et al., 2020). These measures are a small but necessary step in building a confidence society, where mistrust and pessimism do not further corrode the social tissue (Collectif, 2016). Infectious diseases have always been an existential threat to mankind (Shaw-Taylor, 2020). Before the emergency of antibiotics or vaccines, i.e., for most of human history, the unexpected introduction of infectious agents could mean the decimation of some immunologically naïve groups. Besides the physiological immune system, we evolved behavioral immune responses that protect us against pathogen threats and infectious hazards in a more proactive way (Schaller, 2011). Those responses, however, operate mainly subconsciously (Mercier, 2020), and similar to other evolved threat management systems, behavioral immune responses are characterized by contextual sensitivity and biases that aid adaptive responding (Haselton et al., 2015; Ackerman et al., 2018). Though people are usually wary of other people's opinions or advice (Trouche et al., 2018), they are susceptible to repetition, i.e., repeated statements tend to be rated as more likely to be true (Trouche et al., 2018), the so-called “illusory truth effect” (Hasher et al., 1977; Pennycook et al., 2018). During times of elevated stress, such as the ongoing pandemic, our faulty decision-making heuristics are more susceptible to be targeted by groups trying to control the public narrative to their benefit (Starcke and Brand, 2012). Though this procedure is not new, the danger to public health demands a prompt response from society. Words have consequences, and they have been used carelessly in the current pandemic by elected officials, contributing to confuse the public and discredit scientific expertise in the fight against SARS-CoV-2. PP, AS, and AP wrote the manuscript. All authors contributed to the article and approved the submitted version. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Ackerman, J. M., Hill, S. E., and Murray, D. R. (2018). The behavioral immune system: current concerns and future directions. Soc. Personal. Psychol. 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Sociol. 5:560681. doi: 10.3389/fsoc.2020.560681 Received: 09 May 2020; Accepted: 13 October 2020; Published: 12 November 2020. Edited by: Reviewed by: Copyright © 2020 Pereira, Silveira and Pereira. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Antonio Pereira, [email protected]

Public health screening for COVID-19 and its mutations are becoming a routine activity, as we assess the safety of resuming interactions with each another. Control efforts have included social distancing, hygiene, masks, and lockdowns. Where available, testing can confirm exposure to COVID-19. Prior to testing, screening is conducted, typically consisting of assessing one's temperature and asking questions related to symptoms and exposures. However, the efficacy of symptom-based screening (temperature and self-report) for COVID-19 has been called into question in recent studies for both the general population and healthcare workers (1, 2). Older adults are another population in which symptom-based screening for COVID-19 should be questioned. As the pandemic unfolded, older adults have been hardest hit. The statistics are staggering, with older adults making up 45–80% of all hospitalizations, 53% of intensive care admissions, and 80% of deaths (3, 4). However, the media's tone has been that this was not alarming but expected due to age and comorbidities. This paper offers suggestions to mitigate these statistics. The presence of fever is a key clinical indicator of infection and inflammation (5). Thus, the initial objective screening for COVID-19 has been using temperature measurements to diagnose the presence of infection. Of the general population, 98% of the COVID-19 patients was found to have a fever, along with other symptoms (6). Fever is defined as a temperature of 100.4°F (38.0°C) or greater (4). However, studies have found that older adults show a lower core body temperature, described as below 98.6°F (36.4°C), using the standard definition of a fever is a less useful indicator of infection with older adults (7, 8). Other studies have found that baseline temperatures may be as low as 94°F (34.4°C) for older adults (9). In a study of 35,488 participants with a mean age of 52.9 years, the baseline temperatures declined with age (−0.02°C every decade, p< 0.001) (10). In a sample of 18,630 (aged 20–98 years) with a mean age 58.0 years with equal numbers of male/female participants, researchers found an average basal oral body temperature of 97.3°F (36.2°C) (11). A study of 2410 hospitalized patients with influenza aged ≥65 years found a lower temperature threshold 99°F (≥37.2°C) and captured 78% of influenza-positive individuals, while the CDC's threshold for a fever 100°F (37.8°C) captured only 57% (12). Lower baseline temperatures may result in overlooking fevers. In fact, upwards of 30% of older adults with serious infections show a mild or no fever (7, 13). One study found older adults (N = 1,318), presented to the emergency department with influenza 2–5 days after symptom onset (14). In other studies, seeking treatment occurred up to 1 week after symptom onset (15, 16). This delay in seeking health care increases their mortality risk (14). Therefore, the objective measure of a temperature and the threshold of 100.4 F as a fever indicator does not provide a sufficient indicator of infection in older adults and may delay the diagnosis and treatment for COVID-19 (15, 16). Similar to a fever, older adults lack other usual signs and symptoms of illness onset or exacerbation. Atypical presentations could just be a change in cognitive status or mobility. COVID-19 symptoms include fatigue, body aches, weakness and an increasing loss of taste and smell (17). Each of these symptoms may be dismissed as a normal part of aging. Other symptoms, such as coughing, or shortness of breath may be normal for existing chronic conditions such as chronic obstructive pulmonary disease (COPD) or congestive heart failure (CHF). Older adults with COVID-19 do show typical symptoms such as shortness of breath, fever, and cough; however, many of them do not (17). Atypical presentations of COVID-19 in older adults include a delay in fever and respiratory symptoms. COVID-19 symptoms may present themselves anywhere from 4–5 to 14 days after exposure, which may be too late for initiating interventions and having positive outcomes (18). In April 2020, an emergency room doctor observed COVID-19 patients without visible signs of dyspnea and a SpO₂ below 90%. He noticed that these patients had a form of oxygen deprivation, which is difficult to detect, called “silent hypoxia,” despite the patients feeling alert and breathing normally (19). Asymptomatic hypoxia (AH) or silent hypoxia is becoming more prevalent in the COVID-19 literature and is associated with extremely poor outcomes (20). In many cases, AH is associated with a delay in care as the presence of hypoxemia is not identified in the absence of dyspnea (21). In a study from prehospital first responder data, a higher discrepancy was found between oxygen saturation (SpO₂) and respiratory rates in COVID-19 Acute Respiratory Failure (ARF) patients compared to earlier non-COVID-19 ARF patients (22). Without an SpO₂ measurement, normal breathing rates could mask profound hypoxia and make the assessment of severity more difficult in an out-of-hospital setting. Providers must remain attentive while checking for a 3–5% drop in SpO₂ after mild activity/ambulation, room air, and the presence of hypoxemia without tachypnea (19, 21). However, these symptoms may not be occurring in a clinical setting but at home. For this, there is a portable device: the pulse oximeter, which may detect “silent hypoxemia” in older adults with COVID-19, to be used at home or in a community senior-living setting (22). Pulse oximeters are a noninvasive and painless device that measures oxygen saturation levels in the blood (22). COVID-19 pandemic studies are finding increasing value in using pulse oximetry devices. Studies include the usefulness of oximeters in low-resource settings and predicting clinical deterioration (23, 24). A study evaluating 22 prognostic models for COVID-19 found peripheral oxygen saturation on room air and age was a predictor of clinical deterioration and mortality. In addition, the authors recommended that oximeters should be used in initial screenings as well as community-based monitoring (24). Given its potential efficacy for detecting changes in SpO₂, pulse oximeters should be considered to screen for COVID-19 AH in older adults (25, 26). Oximeters are now available as a small, portable, and inexpensive device that can measure SpO₂ at home. Smartphone apps are being developed so that oximeter readings can be downloaded (using a Bluetooth connection) to the phone and shared with providers. While inaccurate oxygen saturation readings are possible due to incorrect finger placement, nail polish, cold fingers, anemia, or device quality, pulse oximeters may be a valuable screening device for COVID-19 in acute and non-acute settings (25). Detecting AH is critical for the prevention of infection progression and initiating treatment. Earlier interventions could help patients avoid highly invasive procedures (i.e., intubation and mechanical ventilation) and improve the allocation of scarce healthcare resources (25). One pulse oximetry study using a cutoff of SpO₂ of 92% decreased the need for hospitalization for COVID-19 positive patients. Checking their SpO₂ regularly provided patient reassurance and reduced emergency room visits (26). The absence of shortness of breath in an older adult should not be considered to be a good sign. In these patients, pulse oximetry is an important means to improve COVID-19 outcomes (20). Across the nation, testing continues to be inadequate, and temperature screening remains the primary initial objective assessment for COVID-19. The recognition of atypical presentations of infection and physiological aging changes in older adults requires us to implement additional methods of screening to guide clinical decision making. The diminished febrile response in older adults is a serious disadvantage and suggests fever thresholds should be decreased (9). The absence of shortness of breath in an older adult with comorbidities should not be considered as a sign of well-being. The poor prognoses of asymptomatic hypoxia underscores the severity of this clinical presentation (20). As the absence of fever does not always rule out the presence of an infection, could the screening for “silent hypoxia” help identify older adults with COVID-19 pneumonia earlier? If so, intervening sooner could potentially decrease mortality rates, before the infection progresses to a point of a fever, and the COVID-19 battle is lost. Halting the spread of the virus among older adults is a challenge, especially in settings where it may be difficult to quarantine, implement social distancing and encourage cognitively impaired older adults to wear masks (27). As screening is essential; decreasing fever thresholds and adding AH screening via a pulse oximeter to routine vital signs is not an unrealistic nor cost prohibitive goal. Symptom-based screening for COVID-19 is a less than precise endeavor, and data being collected during this pandemic is finding that temperature and self-report of exposure and/or symptoms are missing more than 50% of infected individuals (28). Research is needed to determine the most appropriate screening assessments for various infectious diseases and the cohorts exhibiting variations from standard physiological norms. Clinical presentations and physiological differences in older adults should compel healthcare providers to reconsider current assessment and treatment algorithms. For our most diverse population with considerable variations in illness presentations and disease courses, more appropriate and faster clinical decision making is required. No assumptions should be made that a poor prognosis is part of aging when improvements in public health screening may be achieved and the mortality rate of COVID-19 may be reduced or eliminated. CV developed the concept of the article and wrote the manuscript. DE consulted on content and edited the manuscript. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. 1. Callahan A, Steinberg E, Fries JA, Gombar S, Patel B, Corbin CK, et al. Estimating the efficacy of symptom-based screening for COVID-19. NPJ Digi Med. 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Estimated effectiveness of symptom and risk screening to prevent the spread of COVID-19. Elife. (2020) 9:e55570. doi: 10.7554/eLife.55570 PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: older adults, COVID-19, silent hypoxia, temperature, pulse oximeter, atypical presentation Citation: Van Son CR and Eti DU (2021) Screening for COVID-19 in Older Adults: Pulse Oximeter vs. Temperature. Front. Med. 8:660886. doi: 10.3389/fmed.2021.660886 Received: 05 February 2021; Accepted: 23 March 2021; Published: 14 April 2021. Edited by: Reviewed by: Copyright © 2021 Van Son and Eti. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Catherine R. Van Son, [email protected]

Laboratory tests are an important component in the diagnostic process. From an analytical point of view, most tests have reached high technical standards resulting in quantitative results with very high precision and accuracy. The challenge for the clinician then is how to interpret those results. It is particularly difficult when different test systems use different scales and arbitrary units for a given biomarker, as is often the case in immunologic testing. For the clinician it is demanding to estimate the predictive value of a diagnostic test result. A solution to this problem that is advocated here is to provide likelihood ratios as a measure of the predictive value of test results. This approach is not only useful to harmonize interpretation between assays and assay platforms but can be employed as well in external quality control programs. However, the concept of likelihood ratios in clinical diagnostics, although not new, is not yet generally accepted and needs further promotion by demonstrating its usefulness. Some 55 years ago, a “technic for the estimation of the predictive value of diagnostic test results in the subject tested when the sensitivity and specificity of the test and the prevalence of the disease in the population are known” was described (1). At that time, the technic was limited to dichotomous, qualitative test results. Later, the approach has been extended to intervals of test results and their likelihood ratio (LR) (2–6). The LR of a diagnostic test result is defined by its likelihood in diseased subjects (sensitivity) versus non-diseased subjects (1-specificity). In the field of autoimmunity, test result interval-specific LRs have been applied for the diagnosis of rheumatoid arthritis (7, 8), vasculitis (9, 10), systemic rheumatic diseases (11–16), inflammatory bowel disease and celiac disease (17–22). It has been realized that expressing results in the form of LRs provides a convenient way to harmonize test results which otherwise would be expressed in various units and provider-defined scales, making it difficult to compare results. This has led to a proposal for harmonization of anti-neutrophil cytoplasmic antibody (ANCA) testing (23, 24), antinuclear antibody testing (25, 26) and autoimmunity tests in general by reporting test result-specific LRs (27, 28). The calculation of LRs of test result intervals has been further extended to arbitrary quantitative test results (29, 30) and applied, for example, for the diagnosis of Alzheimer’s disease (31), ANCA testing (24), antinuclear antibody testing (26) and celiac disease (22). For the clinician, LRs could be a valuable diagnostic measure (32–35). Nevertheless, a wide application of LRs in diagnostic laboratory testing is not observed today. This might have different reasons, such as: ● a LR is related to a specific diagnosis and, habitually, the clinician does not inform the testing laboratory on the precise diagnostic question. ● a test might be used for screening purposes resulting in a differential diagnosis. ● there is a dearth of data on LRs (and consequently laboratories do not report LRs). With regard to the differential diagnosis, it should be noted that LRs for each differential diagnosis are very valuable to estimate the relative weight of possible diagnoses (36, 37). Establishing LRs needs clinical studies to be performed, either by the in vitro diagnostics industry, the laboratories, or a collaboration of both. As this has a cost, reimbursement of laboratory tests should consider the additional clinical value of the diagnostic information given by the LR (38), which is not the case today. The field will benefit from applying LRs as quantifiable diagnostic values of laboratory tests and as means for harmonizing otherwise incompatible quantities of test results. The Receiver Operating Characteristics (ROC) curve of a test is a good basis for establishing LRs. Such ROC curves are routinely established to choose a cut-off for qualitative readouts and for calculating the area under the curve (AUC). On ROC curves the LR of a test result interval is given by the slope of the corresponding secant to the curve between the two endpoints of the interval (Figure 1) (39). Making the interval smaller and smaller the LR of a single test result is reached as the slope of the tangent to the ROC curve at the point corresponding to the test result (Figure 1) (39). Figure 1 ROC curve with AUC. The slope of the secant (green) gives the LR of an interval of test results and the slope of the tangent (red) for a specific quantitative test result. Since the AUC expresses the discriminant power of a test, the test producer has a high interest to publish such ROC curves. Usually only the graphical display of the curve or even only the AUC and the cut-off are published, but not the test result values corresponding to the individual points of the curve. Some publications shared the complete ROC curve dataset, which allowed to calculate the LRs using the Bézier curves method (31). Based on published ROC curves on fasting capillary glycemia testing (40), D-dimer testing (41), PSA testing (42), HbA1c testing for gestational diabetes mellitus (43), and an Alzheimer’s test (44), we determined test-result specific LRs. These data are given in Supplemental Data Figure 1. Having access to the raw data of clinical studies and the LRs, the next step will be to guide the clinicians to understand the use of LRs. One way certainly is to apply LRs in differential diagnosis. As an example, when performing antinuclear antibody tests (ANA) for screening for connective tissue disease one would get different LRs for different diseases. This would allow the clinician to weigh the suspicions derived from other clinical data. Based on published data on antinuclear antibody testing (45), we deduced the titer-specific LR for the various systemic rheumatic diseases. The results are shown in Supplemental Data Figure 2. Another advantage of using LRs is the harmonization of different techniques, scales, units etc. (24). It certainly would make it easier for the clinician to interpret one single scale, namely LR, than having to get acquainted with different titers, units/ml, ug/ml, mmol/l etc. Even tests using the same scale are not always comparable between different test producers but could be harmonized with LRs. Clinical guidelines giving clinical decision limits for certain test results could improve on such harmonized LRs, not only for dichotomous readouts (46, 47), but also for quantitative results. LRs have a direct function in estimating the probability of a diagnosis. According to Bayes’ theorem the pretest odds multiplied by the LR of the test result give the posttest odds. Now, the clinician in daily practice may not be used to thinking in such numbers of probability but would rather develop an intuition for them. Nevertheless, when it comes to explain, defend, and document a diagnostic decision, LRs would be very helpful. Estimating the pretest odds might be the more difficult part. Starting from the prevalence of the disease in the population to which the patient belongs, the clinician usually adds the anamnestic and clinical findings leading to the use of a laboratory test in order to include or exclude the suspicion. A low suspicion would need a much higher LR for inclusion than a high suspicion and, conversely, a high suspicion would need a much lower LR for exclusion than a low suspicion. For example, when testing healthy pregnant women for HIV-infection the pretest odds would be around 1:100’000. Receiving now a positive screening test from the laboratory a confirmation would of course be necessary, which usually needs a second blood sample. But what should the doctor tell the patient in the meantime? Above what level of screening test results is the LR starting to get higher than 1? HIV-Screening tests have a very low cut-off to reach a maximal sensitivity, but this leads to the fact that low screening results have an LR smaller than 1. The same holds for anti-nuclear antibody screening by indirect immunofluorescence. A low titer positivity (e.g.) 1:40 or 1:80 has a low LR (<1) for systemic rheumatic disease (14). In daily practice, the clinician probably is not thinking in terms of pretest probabilities or even pretest-odds. However, the clinical experience provides a level of premonition for a diagnosis that should be confirmed or refuted by the laboratory test. To what extend such change of suspicion is valid depends of course on the quantitative level of the test result. For standardized and frequently used tests, the clinician would intuitively have a feeling for how much the quantitative test result assures the diagnosis. But often, especially in non-harmonized test systems and when the result is at a level near the cut-off point between positivity and negativity, the information content of the result will be overestimated and therefore misleading. As an example, we recently defined for 8 different ANCA test systems assay-specific test results that corresponded to a LR of 0.1, 1, 10 and 30 (24). For the different assays, the test result that corresponded to a LR of 10 was 35 Units, 48.5 CU, 8.6 IU/mL, 2.8 AI, 10 IU/mL, 13.8 U/mL, 48 U/mL and 10.7 IU/mL (24). All these values have the same clinical meaning, namely that the chance to find such value is 10 times higher in patients with ANCA-associated vasculitis than in individuals without an ANCA-associated vasculitis. The provision of LR values would give the individual results a meaning without knowing the scales and cut-offs. When LR values will be reported by the laboratories, together with the quantitative results, the intuitive diagnostic estimation of the clinician will get with time a new dimension that is generally applicable, independent on the specific test. The diagnostic information provided by a LR of 3, 10, 30 or 100 will get a semantic content on how much secure the clinician can be in the daily routine, without calculating probabilities. Another example that we recently worked out is on antinuclear antibodies (ANA). Lately, platforms that measure fluorescence intensities have been introduced into clinical laboratories. We defined the light intensity units that corresponded to a LR of 0.1, 0.33, 1, 3 and 10 for the NovaView, an automated ANA system from Inova Diagnostics. By doing so we found that the light intensity unit that corresponded to a LR of 0.1 was very close to the cutoff for positivity proposed by the company (26). This means that values that correspond to the cutoff are 10 times more likely to be found in individuals without an ANA-associated rheumatic disease than in patients with an ANA-associated rheumatic disease (which was in agreement with the many false positives reported by the clinicians). We report the LRs for ANA-associated rheumatic disease associated with the ANA fluorescence intensities, which helps the clinician with interpreting test results. One could even go a step further and define pattern-specific LR. Indeed, we demonstrated that the positive predictive value of ANA depends on the pattern, with the highest positive predictive values for the centromere pattern (48). Finally, we also associated LRs to tissue transglutaminase antibody levels and this revealed that cutoffs are not aligned between manufacturers (22). Here again, test result specific LRs could help to align results between manufacturers. A further aspect in using LRs by the laboratory is that it can be applied in external quality control. It is nowadays standard for clinical laboratories to take part in external quality controls. When starting to provide LRs of test results to the clinicians it would be important to also compare LRs with other laboratories. Upcoming differences would probably rather have their origin in the different specifications of clinical studies used to establish the ROC curves than in the technical procedures in the laboratory. This would be important to find out to improve harmonization of tests. It might lead to harmonize clinical diagnosis. We here presented the concept of LR and illustrated its application in autoimmune serology. There are several advantages in applying LR to communicate the diagnostic value of a test. It allows to report test result- (or test result interval)-specific information and to harmonize interpretation between assays and assay platforms. It can not only be applied for specific diseases, but also in differential diagnosis. The concept can also be employed in external quality control programs. The advantages of using LRs in autoimmune serology is being recognized by experts and in vitro diagnostic companies and using LR has been proposed by international organizations (EASI, EFLM, …) as a convenient way to harmonize ANCA test results. Major efforts still need to be done in order to get the concept more generally accepted and applied. The authors contributed equally to the manuscript. All authors contributed to the article and approved the submitted version. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fimmu.2021.655262/full#supplementary-material Supplementary Figure 1 | ROC curves with test result values (o) corresponding to the individual points of the curve (left) and LR as a function of test results (right) as calculated by the Bézier curves method (29). Test results with LR=1 are indicated in red. (A) Fasting capillary blood glucose as a screening test for diabetes (40). (B) D-dimer testing for suspected pulmonary embolism in outpatients (41). (C) PSA testing Gleason grade ≥7 vs Gleason grade <7 or no cancer (42). (D) HbA1c Test as a Tool in the Diagnosis of Gestational Diabetes Mellitus (43). 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This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Walter Fierz, [email protected]

The twentieth century saw the gradual disappearance of the heroic individual doctor and the emergence of specialities with distinct governance structures through colleges and societies. These defined training and issued qualifications. In our world, cardiothoracic surgery split from general surgery, pediatric surgery from general surgery and ear, nose and throat surgery emerged in parallel. The separation produced rapid advances in each field but, as an unexpected consequence, the disciplines grew apart, developing their own ways of working and their own tribal cultures. Our patients (and their conditions) did not recognize this, and they would find that the way in which their disease was treated varied widely–defined largely by the speciality with which they first came into contact. The management of complex airway disease in children exemplifies these problems, but also offers a solution. In the late twentieth century, patients were referred to individual surgeons who applied the skills of their own discipline to varying, but imperfect effect. Inter-discipline referral was rare, and sometimes difficult because the geographic location of services had become separated to different hospital sites in previous years. Sadly, and as we all now know, affected children often had problems which crossed the constrained boundaries which we physicians had drawn up. Tracheal stenosis is often combined with cardiovascular anomalies and genetic abnormalities are frequent. Upper gastro-intestinal tract issues including swallowing problems abound. Patients attending one speciality were referred to another for consultation on a transactional basis. Indeed, in dominantly private healthcare systems, this remains the case, as it can increase incomes to all parties. This slows decision making, fails to integrate views effectively and weights decision making in favor of the physician to whom primary referral is made. Our primary aim as physicians is “first, do no harm.” As Hull and Sevdalis pithily stated (1) “Teams create safety,” and as we hope to outline in this paper, teamwork also improve outcomes, creates efficiency, reduces cost and promotes research. Achieving these goals is good for patients and for the wider healthcare system. In the United Kingdom in the 1980s and 90s, referrals for small children with long segment congenital airway stenosis (LSCTS) passed through a series of gateways to pediatric or cardiac intensive care units, largely because of the resuscitative skills held by the staff there. Surgery tended to default to cardiac surgical teams because of the high incidence of associated cardiovascular anomalies and the need for cardiopulmonary bypass for repair. The incidence is low, and so each center saw a tiny number of patients, and experience was hard to acquire. There were only a few short case series in the literature upon which to base treatment choices, and few contained sufficient detail to be confident about all the relevant technical details and none had any long-term data. Several techniques had been described for repair, but patch tracheoplasty dominated, and mortality rates were high. At that time, relevant skills were distributed in such a way that individuals had to be consulted to manage specific problems. For example, endoscopic examination of the airway was largely done by ear, nose and throat (ENT) surgeons, cardiologists helped diagnose and manage cardiac issues, and the surgical reparative skills crossed boundaries. Intensive care was mandatory, but often seen as a “service” to other teams, and nursing was undervalued. Interventional radiology was embryonic, but increasingly seen to be relevant, and palliative care was only a consultative service. The interfaces between services were relatively formal; a consultative interface. As Reason pointed out many years ago (2), it is the interfaces which go wrong and lead to error because of failures in communication. Each discipline approached problems in its own way according to its own (often limited) experience. Those of us involved in the care of these children decided that this was not good enough and everyone involved met in 2000 to work out how we might better deal with complex airway cases. It was the birth of the GOSH¹ Tracheal Team, and a fantastic meeting of minds. Several key decisions were made; • The team should comprise all those coming into contact with such patients on a regular basis. Namely, but in no specific order of importance, cardiothoracic surgeons, ENT surgeons, interventional radiologists, specialist and intensive care unit (ICU) nurses, intensivists, respiratory physicians, pediatric general surgeons, anesthetists, diagnostic radiologists, speech therapists, physiotherapists, administrative staff, data managers, radiographers, cardiologists, and interested researchers and junior staff in training. • A leadership structure was created. • ALL referrals with complex airway problems would be reviewed by the Tracheal Team at a weekly multi-disciplinary team meeting (MDT). • ALL relevant decisions about both individual patient care and overall strategy would be taken at the MDT, recorded and stored in a database. • LSCTS would be treated by slide tracheoplasty on cardiopulmonary bypass or extracorporeal membrane oxygenation (ECMO), and where possible, cardiac lesions would be repaired at the same time. • The team should learn to cross-skill to avoid delays to patient care. Specifically, this related to skills in fibreoptic bronchoscopy and balloon dilatation. • All outcomes would be published, and attempts would be made over time to centralize care in the UK if results justified it. • Links would be created with other interested specialists throughout the world. Within just a few years we observed a significant increase in referral, improved outcomes and a dramatic reduction in the cost of care (3). Such single center reporting is prone to bias and uncertainty as to the cause of the improvement, but we maintain that all of the above decisions contributed in some way. We also noted greater cohesion, smoother decision making, constructive discussion and general happiness in the mode of working. Several other teams emerged simultaneously, notably in Chicago and Cincinnati, from different origins, and also commented on the value of integrated teamwork [see discussion at the end of (3)]. The growth of referral accelerated our learning, and the rate of improvement of results changed with it. In 2005–6 the team applied for, and was granted, national status by the National Health Service (NHS), becoming the sole center recognized for the treatment of complex airway disease in children. Since then growth has been continuous, with referrals coming from all over the world, bringing with it new challenges and increasing complexity of cases. Research blossomed, ranging from diagnostic techniques through to quality of life assessment, cell biology and transplantation. Our team was successful, and its teamwork “worked.” We are particularly proud of the way in which certain roles developed within the team. Specifically, and against some initial resistance by vested interests, the radiographer in our team was taught to undertake bronchoscopy and balloon dilatation, a skill which now makes her one of the world leaders in this field and a significant contributor to the literature. We will return to cross-skilling later. Is our experience unique, or are the consequences of good teamwork replicable? There has been a great deal of work undertaken about the importance of teamwork in surgery, and an excellent review of the relevant background for surgeons by the Royal College of Surgeons of England (RCS). This can be found at www.rcseng.ac.uk/surgeons/surgical-standards/professionalism-surgery/gsp. It is widely accepted that good teamwork improves clinical performance (4), patient outcomes (4, 5), and the well-being and retention of staff (6, 7). The effect on performance appears to be present even in a limited part of the patient journey, i.e., in the operating room (8). The RCS report highlights the point that teams come together to perform specific tasks, and thus the membership of the team must be capable of achieving that task together. In high performing teams, members (6, 7): • Understand their own and other members' roles and responsibilities • Encourage contributions of all members and ensure that the views of new and junior members are taken into account • Show respect for the role, expertise, competence and contributions of allied disciplines and healthcare providers. • Respect the leadership of the team • Have the shared goal of high-quality care for the patient • Show a commitment to teamwork in the best interest of the patient • Recognize they are important to the outcome of the task • Feel confident to raise their voice or intervene. It is wonderful when one finds oneself working in an effective team. Sadly, it is much more common to find oneself in a group. Giddings and Williamson (9) created a fascinating table which very clearly reveals the differences between a team and a group, which we reproduce here; Some key points emerge from this table, and these are reinforced by our own experience and from watching other teams/groups in action. Consensus, clarity of goals and understanding of roles may seem obvious, but the hiding of feelings is perhaps less so. How many of us can remember being in meetings in which half the people in the room do not contribute to the decision making, but can be found moaning in the corridor about the decision that was made? This reflects a dangerous lack of confidence in not speaking up (always dangerous for patients) and a lack of leadership in bringing everyone's views to the fore. It does not do, either, to have a leader foisted on a team; better to let the team choose its leader and be ready to change leadership as and when circumstances change (and they always will). Good teams are self-analytical; happy to consider their own effectiveness and to make changes rapidly when required. We are all aware that teams can be dysfunctional and have probably experienced situations in which an individual has thrown the train of successful teamwork off the tracks, derailing the team. Another great table from Giddings and Williamson (9) [based on the work of Hogan and Hogan (10)] looks at the characteristics of strong team members and those who tend to derail (see below). A quick glance down the “derailer” column usually prompts memories of specific individuals by anyone who reads it. It is also highly reminiscent of some world leaders at the time of writing! Teams in healthcare are often larger than is ideal, and leadership is critical for effective performance. There is evidence that leadership clarity in healthcare environments improves both teamwork and innovation (11). But what good leadership actually really means is harder to define, and it is salutary to think about it from the team members' perspective as Goodwin discussed (12). Team members define the most common positive attributes of healthcare leaders to be; intelligence, ability, confidence, warmth and friendliness, benevolence, emotional stability, integrity and the abilities to delegate and communicate. There seems nothing to argue about in this list. In our view, these are attributes to which leaders of teams in our field should aspire, and by which they should be judged. We have alluded to the wide membership of our own team in London, and it is worth considering why that should be necessary in a little more detail. As our team has evolved, the differences in core skills between the various members have become evident. This is best demonstrated by considering some examples. • Within their discipline, ENT surgeons have developed skills in endoscopy (rigid and fibreoptic) and trans-endoscopic surgery. They are confident with very difficult airways and have had to work closely with specialist anesthetists to ensure the safety of their patients. They have specific technology and imaging experience and themselves often work in wider teams, for example in tracheostomy management. Culturally, ENT surgeons often receive direct referrals and stay in close contact with individual patients throughout the course of care, leading the management decisions. • Cardiothoracic surgeons used to be just that, although it is becoming more common for cardiac and thoracic skills to be separated after appointment to the consultant (attending) staff, especially in pediatrics. Cardiac surgeons clearly are used to repairing the heart and blood vessels and to the use of cardiopulmonary bypass and ECMO. Both these latter can be lifesaving in severe airway problems. Cardiac surgeons are also used to working under time pressure because of the limitations of cardioplegic myocardial preservation, and to do so in a complex multi-disciplinary team of their own. Referrals usually are made to a team, via pediatric cardiologists and culturally almost all decisions are made in formal MDT meetings. Follow up of individual patients is often not directly with the surgeon, but by other members of the team, especially cardiologists and specialist nurses. • Radiologists have a wonderful grasp of available technology, excellent dimensional interpretive skills and cross disciplines in their knowledge of diagnoses. In our world, this has led to developments in MR (flow dynamics), CT (4 D assessment of the airway), optical coherence tomography and advanced bronchography. The development of interventional radiology has involved them increasingly in therapy and follow up including endoscopic or physiologic imaging. The development of balloon dilatation of airway and image-guided surgery has further expanded the role of radiology in airway disorders. Culturally, radiologists have rarely had longer term follow up as part of their job description, with referral on each occasion usually being on a “form—request” basis. They have always been deeply involved in MDTs from a diagnostic perspective, but increasingly they are crucial members of the team in determining therapeutic options and the role in decision making is continuous. • Pediatric cardiologists are integral to service delivery. Eighty percent of our patients have had cardiovascular problems, often complex, and cardiac diagnosis and non-surgical intervention fall within the realm of the cardiologists. They have a huge role to play in deciding the timing of interventions, and involvement in the MDT is essential for complex patients. • All the above groups have a tendency to be “activist,” anxious to do something practical to intervene for the better. Such views need balancing, and the voice of the pediatric respiratory physician is crucial in this regard. It is often more valuable to the patient and his/her family to avoid surgery and the wisdom of someone who sees patients over time with detailed physiological and holistic assessment is of great importance to the team. • The role of the nurse in the team cannot be underestimated. We have found it best to have a specialist “tracheal” nurse as the leader of the nursing team, and they have the front-line responsibility of communicating regularly with the families. It often comes as a surprise to surgeons that patients find them intimidating. This is rarely the case with nurses, who better grasp the wider needs of the patient and who take on a huge burden of communication with community services. Some of the most common complaints made against hospitals relate to difficulty in contacting the relevant person or failing to be called back with detail when promised. This is exactly what a well-trained and sympathetic nurse does well. Communication is everything. • Administrative staff are needed to oil the wheels of the machine. The quality of service is dependent on them, and it is best to have them involved in all MDTs and team meetings. They ensure proper communication with other services and the family, and also help with maintaining the records and database, facilitating later research. They provide a great deal of support to families in practical, non-medical interactions with various authorities; many of these children have additional problems and appointments with hospital, school, social worker etc., all need to be coordinated to make a “one-stop shop” possible as often as possible. This is customer service. Some provide good service naturally, but it can be trained and should be expected. • The remainder of the team comprises physio- and speech therapists, researchers and junior staff. Their role is variable, but they have much to offer; each will learn more about the patient and their voices should be heard. Ross Brawn, the great Formula One manager, in describing what it takes to win a Formula One championship said (13)² that “everyone in the team should aspire to be World Champion at what they do.” This is an important concept, reflecting disseminated ambition, strong leadership and a philosophy of excellence. Mostly, though it expresses the value of every member of a team in contributing to its success. People who fail to contribute to the team might better be employed elsewhere. These are the human factors of surgery (14, 15), a field of study drawn from organizational psychology and of proven performance value in many industries, particularly aviation (16, 17). The team leaders should ensure that these human factors are monitored and appropriately maintained as time goes by. They need also to consider the impact of their own style (which can be measured) on others (18). Most teams in medicine never have their team performance assessed. There are good examples of such assessment in certain specific areas, notably in anesthesia (19), emergency medicine (20), intensive care (21), and the operating room (22) in all of which there are good opportunities for simulation. The lack of assessment of complex teams with responsibilities for human lives is a situation that would not be allowed to exist in other high reliability organizations where regular human factors audit is regularly undertaken and is often part of licensing, for example the Line Operations Safety Audit to which commercial pilots and their teams are subject (16). Although not mandatory, it might be considered good governance for airway teams to subject themselves to such review. Medicine is changing fast. The impact of technology, particularly in imaging, minimally invasive surgery and communications has been immense and is accelerating. Changing patterns of referral change the demands on the team as time passes. Teams should not be static in such a context. Membership should be reviewed; the unnecessary should be redeployed and new relationships fostered as demands change. In our own team two developments over the last decade have driven the need for change. The first has been the development of tracheal transplantation in various forms (23, 24) and the increased incidence of button battery injury (25). For the first, we needed to involve a wide range of scientists, adult research teams and international contacts. They worked at multiple institutions but were able to join our MDTs and research meetings thanks to video conferencing. Not only was this necessary to manage the individual patients, but it added skills we lacked, and which have subsequently become integral. Notably, the integration of clinicians caring for adults helped us better to plan the transition of care from pediatric to adult practice and ensure the lifelong follow up necessary to determine the value of any intervention (26). For the second, close collaboration was needed with general pediatric surgeons with primary responsibility (and understanding) of the esophagus and its surgery. Our team has thus changed its structure and now its name as a result. It is called the aero-digestive team. This reflects the changing pattern of work, and also how joint enterprise in a team format has meant that previously untried techniques are being developed to solve major problems (25), based on the respective skills of the team members. If close integration into team activities had not occurred, and if treatment was based on referral rather than working together as one team, these advances are unlikely to have been made. Once again, referrals are increasing, and the benefits of specialization are evident. The more you do, the better you get. There is an old Chinese proverb³ which goes “Those who have knowledge don't predict. Those who predict, don't have knowledge.” Despite the dangers of prediction, some things are coming our way and we need to anticipate them. There is no doubt that the advent of artificial intelligence and machine learning will have an impact on decision making and outcome analysis. Data are critical to both, and there can be no excuse in the current era for incomplete or inaccurate data collection. Transparency is necessary, and no patient should be excluded from the databases, unless they specifically refuse consent. Asked correctly, and with the altruism of involvement in future benefit, refusal is rare. Augmented reality is developing so fast that many of the interventional procedures we employ will be supported by these techniques, as too will surgical learning and patient understanding. Combining these developments will permit simulation and improved precision. The development of all though will need “volume.” Research is unlikely to be funded for small or unstable teams. Thus, there seems to be a significant rationale for centralizing pediatric airway care around teams of a certain, but undetermined, size and which embrace all the relevant skills. Such teams will benefit from international collaboration with similar teams, especially those of appropriate size. These teams exist and are contributing (27, 28). Research, transparency, partnership and co-operation are critical. As we said at the start of this paper, this is not a sport for individuals but for teams. Yet Brawn remains correct (13); if you want to win as a team, all the individuals must perform to the highest standard. ME wrote the first draft, and all the other authors contributed to the final text and approved it for publication. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. 1. ^GOSH = The Great Ormond Street Hospital for Children NHS Foundation Trust, London. 2. ^Paraphrased. 3. ^Lao Tzu, 6th Century BC Chinese Poet. 1. Hull L, Sevdalis N. Teamwork and safety in surgery. Revista Colombiana Anestesiol. 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Gaslini's tracheal team: preliminary experienceafter one year of paediatric airway reconstructive surgery. Italian J Pediatrics. (2011) 37:51–8. doi: 10.1186/1824-7288-37-51 PubMed Abstract | CrossRef Full Text | Google Scholar 28. Boesch RP, Balakrishnan K, Acra S, Benscoter DT, Cofer SA, Collaco JM, et al. Structure and functions of pediatric aerodigestive programs: a consensus statement. Pediatrics. (2018) 141:e20171701. doi: 10.1542/peds.2017-1701 PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: teamwork, airway surgery, quality, pediatrics, trachea Citation: Elliott MJ, Roebuck D, Muthialu N, Hewitt R, Wallis C, DeCoppi P, Macintyre D and McLaren CA (2021) Teamwork in Airway Surgery. Front. Pediatr. 9:621449. doi: 10.3389/fped.2021.621449 Received: 26 October 2020; Accepted: 20 January 2021; Published: 24 February 2021. Edited by: Reviewed by: Copyright © 2021 Elliott, Roebuck, Muthialu, Hewitt, Wallis, DeCoppi, Macintyre and McLaren. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Martin J. Elliott, [email protected]

Although primary care physicians (PCPs) regularly encounter patients with dizziness or vestibular symptoms, they often consider these patients as difficult, challenging or even heartsink (1, 2). Given the current scientific evidence and available “vestibular tools,” this is unnecessary. We will provide ten vestibular tools that should not be missed, following definition, diagnosis, treatment, and prognosis, respectively (Figure 1). Figure 1. Ten vestibular tools for primary care. When approaching a potentially complex problem, the use of a uniform nomenclature is crucial. To date, most primary care guidelines use the typology of Drachman and Hart (3). This typology distinguishes four dizziness subtypes, i.e., vertigo (rotational dizziness), presyncope (lightheadedness), disequilibrium (unsteadiness when walking), and non-specific dizziness. The Drachman-Hart typology is primarily based on how patients describe the nature of their symptoms, assuming that this will provide etiological insight, and therefore, diagnostic guidance (4, 5). However, both doctors and patients use the term “vertigo” differently (6–8), patients are inconsistent when describing their symptoms (7), the identified subtype does not reliably match the suggested etiology (5, 9), and regularly patients have more than one dizziness subtype (10). Therefore, it is time to leave the Drachman-Hart typology and to adopt a more accurate and uniform way to describe vestibular symptoms. The Bárány society, the leading international organization for clinicians and researchers involved in vestibular medicine, previously realized such a nomenclature: the International Classification of Vestibular Disorders (ICVD) (11, 12). The ICVD identifies four main vestibular symptoms, i.e., dizziness (“the sensation of disturbed or impaired spatial orientation without a false or distorted sense of motion”); vertigo (“the sensation of self-motion when no motion is present or the sensation of distorted self-motion during normal head movement”); vestibulovisual symptoms (“visual symptoms that result from vestibular pathology or visual-vestibular interaction”); postural symptoms (“balance symptoms related to maintenance of postural stability, occurring only while upright—seated, standing, or walking”) (13). These vestibular symptoms are not specific in terms of etiology, not overlapping, and not hierarchical (a single patient can experience multiple symptoms) (13). When assessing a patient with vestibular symptoms, the Bárány society recommends to focus on timing (onset, duration, and evolution of symptom) and triggers (actions, movements, or situations that provoke onset of symptoms) (11, 12). Combining the mentioned vestibular symptoms with timing and triggers results in three vestibular syndromes, i.e., acute vestibular syndrome (AVS), episodic vestibular syndrome (EVS), and chronic vestibular syndrome (CVS). AVS is defined as acute-onset, continuous vertigo/dizziness, lasting days to weeks, generally including symptoms that suggest new dysfunction of the vestibular system (like vomiting, nystagmus, and severe postural instability). Disorders presenting with AVS include vestibular neuritis, labyrinthitis, stroke affecting vestibular structures, and traumatic vestibulopathy. EVS is defined as transient vertigo/dizziness lasting seconds to hours, generally including symptoms that suggest temporary dysfunction of the vestibular system (like nausea, nystagmus, and sudden falls). Disorders presenting with EVS include vestibular migraine, benign paroxysmal positional vertigo, Menière's disease, and panic attacks. CVS is defined as chronic vertigo/dizziness lasting months to years, generally including symptoms that suggest persistent dysfunction of the vestibular system (like oscillopsia, nystagmus, and gait unsteadiness). Disorders presenting with CVS include poorly compensated vestibulopathy, bilateral vestibulopathy, and persistent postural perceptual dizziness (13). In short, the ICVD nomenclature provides an essential tool for the work-up and communication of vestibular symptoms in primary care (tool #1). Up to 40% of patients presenting with vestibular symptoms in primary care remain undiagnosed (14, 15). Although this is not unusual for comparable reasons for encounter (like tiredness), we firmly believe it is possible and necessary to reduce the number of undiagnosed dizzy patients in primary care. An accurate diagnosis starts with thorough history taking, focusing on symptom characteristics, timing, and triggers according to the ICVD. During history taking, the importance of a medication review is apparent. Although an adverse drug effect is a rare cause of vertigo/dizziness in younger patients, it is much more prevalent and regularly missed in older patients. Previous research studies showed that Dutch PCPs scarcely reported adverse drug effect as a cause of dizziness in older patients (1–3%) (14, 15), whereas a diagnostic panel study among the same population found a much higher proportion (25%) (10). Drug-induced vertigo can be caused by aminoglycosides, azithromycin, pregabalin, mefloquine, and α-blockers, whereas drug-induced dizziness can be caused by anticonvulsants, antidepressants, anti-psychotics, β-blockers, Calcium channel blockers, antiarrhythmics, diuretics, vasodilators, anxiolytics, and antispasmodics (16–18). As a medication review costs little time and may provide much insight (i.e., clues for intervention), it should not be missed in the diagnostic phase (tool #2). During such a review, a practical guide may help to rapidly identify potential adverse drug effects (19). A more common cause of episodic vertigo is vestibular migraine (VM). This is a migraine variant with vestibular symptoms and poorly understood pathophysiology. Despite its prevalence and high impact on healthcare cost and utilization, VM remains clinically underdiagnosed (20). The diagnostic criteria for VM include the presence or history of migraine, at least five episodes with vestibular symptoms of moderate or severe intensity and at least 50% of episodes associated with migraine features (i.e., headache, motion sensitivity, photo- or phonophobia, or visual aura) (21). We recommend physicians to structurally ask for migraine symptoms (tool #3), and, if present, consider vestibular migraine (VM). Another small but effective tool, especially regarding older patients, is to incorporate the following question in your diagnostic work-up: Is there another contributory cause of dizziness? (tool #4) According to a diagnostic panel study among 417 older dizzy patients in Dutch primary care, 62% had two or more contributory causes of dizziness (10). Among a consecutive cohort of 621 patients in tertiary care (average age 56 years, range 11–90 years), 30% of dizzy patients had more than one diagnosis (22). If the history reveals red flags (e.g., neurological symptoms, new headache, or acute deafness) (23), it is important to minimize the probability of a central cause of dizziness. However, when sharpening one's diagnostic tools, population awareness is crucial: the prior probability of a central cause of dizziness in a primary care population is very low compared to secondary/tertiary care. In a study cohort that consisted of patients hospitalized with isolated vertigo, the risk for stroke during 4-year follow-up was 3.01-times higher compared to the general population; vertigo patients with three or more risk factors (including age >55 years, male gender, hypertension, diabetes, coronary artery disease, and hyperlipidemia) even had a 5.51-fold higher for stroke (24, 25). However, in a surveillance study among patient presenting with dizziness symptoms to the emergency department, only 0.7% with isolated dizziness symptoms had a stroke/TIA (26). According to the ecology of medical care (27), this proportion will be even lower for patients presenting with the same symptoms in primary care. In case of an acute vestibular syndrome (i.e., rapid onset of vertigo, nausea/vomiting, and gait unsteadiness in association with head-motion intolerance and nystagmus) another promising tool comes in: the three-step Head Impulse–Nystagmus–Test of Skew (HINTS) exam (HINTS; tool #5). The HINTS exam is a simple bedside test that is relatively easy to learn (https://medicinetoday.com.au/vertigovideos). The HINTS exam can help differentiate between vestibular neuritis and stroke, because the presence of any of three oculomotor signs (normal horizontal head impulse; gaze-direction nystagmus; or skew deviation) indicates a central cause of acute vestibular syndrome. A recent systematic review revealed that the HINTS exam has a pooled sensitivity of 96% and specificity of 71% to detect stroke (28), which indicates an even higher diagnostic accuracy than early MRI (29). When revising one's diagnostic tools, it is important to reconsider overrated tools. According to an observational study (n = 2,812), Dutch PCPs performed blood analyses in 22% of older patients presenting with dizziness (15). Until present, there is no scientific evidence that standardized blood analysis has additional value during the work-up of vestibular symptoms. Among 4,538 patients included in etiologic studies, laboratory abnormalities that explained dizziness were limited to three patients with electrolyte disturbances, 11 with glucose disorders, 11 with anemia, and one with hypothyroidism (30). In a community based study, the results of standardized blood analysis among 149 dizzy subjects and 97 controls did not differ (31). Therefore, use blood tests only on a strict medical indication and avoid standard blood analysis in patients with vestibular symptoms (tool #6). A very rewarding vestibular tool is the Epley maneuver (tool #7). This is a relatively simple, safe, and highly effective treatment for the most prevalent cause of episodic vertigo, i.e., benign paroxysmal positional vertigo of the posterior canal—a diagnosis that can be confirmed by using the Dix-Hallpike test (https://www.youtube.com/watch?v=kEM9p4EX1jk&feature=youtu.be) (32). Despite its proven effectiveness, PCPs have not yet embraced the Epley maneuver. During a survey among 426 PCPs, only 57% used the Epley maneuver. The most common reason (50%) for PCPs not to use the maneuver was that they did not know how to perform the technique (33). The second reason (30%) was not being convinced of its effectiveness. Both deserve reconsideration, as the Epley maneuver can be easily learned (https://medicinetoday.com.au/vertigovideos) and the scientific evidence is convincing [Epley vs. sham maneuver, complete resolution of vertigo: OR 4.42 (95% CI 2.62–7.44); Epley vs. sham maneuver, conversion of Dix-Hallpike: OR 9.62 (95% CI 6.0–15.42)] (32). Another effective, safe, and neglected tool is vestibular rehabilitation (VR; tool #8). VR is an exercise based treatment that gradually stimulates the vestibular system and vestibular compensation (34). Chronic vertigo occurs when natural vestibular compensation fails (35). Although a clear definition is lacking (36), chronic vertigo is—based on clinical course and expert opinion—often defined as symptoms persisting more than 1 month (17, 37). In primary care, physicians can refer patients to a specialized physiotherapist for VR. Despite the scientific evidence for VR, <10% of PCPs in the Netherlands and UK reported its use (33, 38). As this may be due to a lack of availability or access to VR (38), the University of Southampton developed a freely available online VR intervention (https://balance.lifeguidehealth.org). This online VR intervention was investigated among two different cohorts in primary care (n = 296 and n = 322, respectively), showing both reduction of dizziness and dizziness-related impairment after 3 and 6 months (39, 40). Being easily accessible, safe, effective and low cost, online VR has the potential to substantially improve the quality of life for a largely undertreated group of patients. Although nowadays VR is the preferred treatment for chronic vertigo according to US, Dutch, and UK clinical practice guidelines (17, 41–43), anti-vertigo drugs like betahistine are still regularly prescribed. According to a large observational study, betahistine was initially prescribed to more than two thirds of vertigo patients in general practice and was still being used after 6 months (44). This enthusiastic prescribing contradicts with the state of the science, though, as a recent Cochrane review showed only weak evidence for the effectiveness of betahistine to treat chronic vertigo (45). Also, long term prophylactic treatment with betahistine does not change the time course of vertigo episodes related to Meniere's disease compared with placebo (46). When using GRADE methodology to compare VR (4 RCTs, n = 565 adults with different causes of chronic vertigo) with betahistine (11 RCTs, n = 606 adults with different causes of chronic vertigo), there is a difference in effectiveness and quality of evidence: vertigo patients receiving VR reported higher improvement compared to sham/no treatment [odds ratio 2.67 (95% CI 1.85–3.86); moderate quality of evidence], whereas vertigo patients treated with betahistine reported limited improvement compared to placebo [risk ratio 1.30 (95% CI 1.05–1.60); low quality of evidence]. In contrast to VR, none of the betahistine trials was conducted in primary care, which limits the generalizability (47). In short, when treating chronic vertigo, use exercise not drugs (tool #9). Until present, many risk factors of handicapping dizziness and/or vertigo have been identified, like chronic dizziness, daily dizziness, activity limitation or avoidance due to dizziness, anxiety or depression, polypharmacy, and impaired functional mobility (48–51). One of the most powerful predictors of an unfavorable course of dizziness, though, is significant impairment at baseline as measured with the Dizziness Handicap Inventory (DHI) (49, 52). The DHI is a 25-item self-report questionnaire, developed to measure impairment due to vestibular symptoms (53). Nowadays, it has been translated in at least 17 languages and considered to be the most used vestibular PROM (54). However, the length of the DHI limits its use in daily clinical practice. Therefore, the abbreviated 10-item DHI-S questionnaire (fill-in time ± 2 min) was developed in 1998 (55). During a psychometric evaluation in primary care, the DHI-S showed excellent criterion validity, test-retest reliability, and responsiveness (56). Recently, a prediction study with external validation in primary care showed that the ability of the DHI-S to identify patients at risk of an unfavorable course of dizziness improved when combined with the predictors age, history of arrhythmia, and looking up as a provoking factor (area under the curve after external validation = 0.78) (52). Given the fact that—in addition to its prognostic qualities—the DHI-S provides information on current handicap and can be used to monitor treatment effect, we believe that this questionnaire should not be missed in the vestibular toolkit of the PCP (tool #10). In this article, we present ten vestibular tools for primary care. PCPs can use these tools to improve diagnosis, treatment, and prognosis of vestibular symptoms. All tools are readily available and do not require intensive training. 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(2020) 126:56–64. doi: 10.1016/j.jclinepi.2020.06.021 PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: vestibular symptoms, vertigo, dizziness, primary care, general practice, diagnosis, treatment, prognosis Citation: Maarsingh OR and van Vugt VA (2021) Ten Vestibular Tools for Primary Care. Front. Neurol. 12:642137. doi: 10.3389/fneur.2021.642137 Received: 15 December 2020; Accepted: 12 January 2021; Published: 12 February 2021. Edited by: Reviewed by: Copyright © 2021 Maarsingh and van Vugt. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. *Correspondence: Otto R. Maarsingh, [email protected]