The Relation of Conjunctival Pallor to the Presence of Anemia

Abstract

To determine the value of conjunctival pallor in ruling in or ruling out the presence of severe anemia (hemoglobin 90 g/L) and to determine the interobserver agreement in assessing this sign. Patients were prospectively assessed for pallor by at least one of three observers. All observations were made without information of the patient's hemoglobin value or of another observer's assessment. Tertiary-care, university-affiliated teaching hospital. Three hundred and two medical and surgical inpatients. Likelihood ratios (LRs) calculated for conjunctival pallor present, borderline, and absent were as follows: pallor present, LR 4.49 (95% confidence interval [CI] 1.80, 10.99); pallor borderline, LR 1.80 (95% CI 1.18, 2.62); pallor absent, LR 0.61 (95% CI 0.44, 0.80). Kappa scores of interobserver agreement between paired observers were 0.75 and 0.54. The presence of conjunctival pallor, without other information suggesting anemia, is reason enough to perform a hemoglobin determination. The absence of conjunctival pallor is not likely to be of use in ruling out severe anemia. With well-defined criteria, interobserver agreement is good to very good.