Data for this article, as in previous reports,1 are drawn principally from Monthly Vital Statistics Report, published by the National Center for Health Statistics (NCHS).2-6 The international data come from the Demographic Yearbook7 and the quarterly Population and Vital Statistics Reports,8 both published by the Statistical Office of the United Nations, which has also been kind enough to provide directly more recent data. Except for mortality data by cause and age, which are based on a 10% sample, all the US data for 1984 are estimates by place of occurrence, based upon a count of certificates received in state offices between two dates, 1 month apart, regardless of when the event occurred. Experience has shown that for the country as a whole the estimates, with few exceptions, are close to the subsequent final figures. There are, however, considerable variations in some states, particularly in comparing data by place of occurrence and place of residence. State information should be interpreted cautiously.
