Kuller, L H. (Johns Hopkins Univ. School of Hygiene and Public Health, Baltimore, Md. 21205), A. Bolker, M. S. Saslaw, B. L Paegel, C. Sisk, N. Borhani, J. W. Wray, H. Anderson, D. Peterson, W. Winkelstein, Jr., J. Cassel, P. Spiers, A. G. Robinson, H. Curry, A. M. Lilienfeld and R. Seltser. Nationwide cerebrovascular disease mortality study. IV. Comparison of the different clinical types of cerebrovascular disease. Amer. J. Epid., 1969, 90: 567–578.—The specific types of stroke as reported on the death certificate or hospital record were compared in areas of the United States with high, low and intermediate cerebrovascular disease death rates. There was no difference in the specific types of stroke listed on the death certificates in the different areas. Of 1, 960 death certificates listing stroke, 108 [5.5%) reported intracerebral hemorrhage, 179 (9.1%) subarach-noid hemorrhage, 483 (24.6%) cerebral hemorrhage, 588 (30%) cerebral thrombosis, 49 (2.5%) cerebral embolism and 595 (30.4%) cerebrovascular disease type undetermined. Many certificates included more than one stroke diagnosis. In spite of the much greater frequency of diagnostic procedures in the low and intermediate as compared to the high cerebrovascular disease death rate areas, the type of stroke listed on a hospital discharge diagnosis was similar in the three area groups, being 27% (337 of 1, 242) cerebral hemorrhage, 12.2% subarachnoid hemorrhage, 37.3% cerebral thrombosis or infarction and 23.3% cerebrovascular disease type undetermined. In general there was a fairly close agreement between the type of stroke that was listed on the hospital discharge diagnosis and death certificate. The validity of the diagnosis of the specific typo of stroke was difficult to determine. For records listing subarachnoid hemorrhage or aneurysm 88% were verified by at least an autopsy examination of the brain, or arteriogram, craniotomy or spinal puncture, while for cerebral hemmorrhage 40.7% and for cerebral thrombosis 47% of the records could be verified.