Prescribed medicines: findings from the National Medical Care Expenditure Survey.

In 1977 the National Center for Health Services Research, US Department of Health and Human Services, undertook a survey of 40,000 individuals in the United States, soliciting information on expenditures and sources of payment for health services including prescribed medicines. Differences in the use of prescribed medicines by age, sex, ethnic/racial background, family income, and perceived health status were found across and within therapeutic categories. More than one-fifth of expenditures were for cardiovascular-renal agents. Sources of payment were similar in all but a few therapeutic categories.