In this report, cases of musculoskeletal disease were identified by a yes response to questions involving joint pain and/or physician-diagnosed arthritis in four national surveys for the following objectives: (a) to assess time trends in case prevalence; (b) to describe respondent health status; (c) to estimate prevalence of joint pain by location; (d) to estimate prevalence of selected comorbid medical conditions; and (e) to estimate among these persons the burden of ADL and IADL disability. These surveys were conducted over a 25-year interval (1960-84). Joint pain is the final common pathway through which a number of these disorders operate and could be expected to identify a subset of persons who have not sought medical consultation. Physician diagnosis of disease is an item that is conceptually a measure of severity. In these samples, there were slightly more persons reporting joint pain than reporting a diagnosis of arthritis in most years. Increases in the prevalence of both joint pain and physician-diagnosed arthritis were noted across survey years and for the cohort aged 65-69 years in NHANES I. Although this analysis is based on national data from persons with arthritis, estimates of disability prevalence from national surveys of the total U.S. population (18,28) are also available for comparison. In this report, persons with arthritis suffer from poorer health status and more disability when compared with U.S. population prevalence. Overall, 14 percent of persons aged 65-74 years reported difficulty walking, and 20 percent of persons with arthritis reported this difficulty. In the U.S. cohort aged 75-84 years, 23 percent reported difficulty walking, compared with 31 percent of those with arthritis. Among persons aged 85 years and over, 40 percent reported difficulty walking, compared with 46 percent of respondents with arthritis. It should be recognized that persons with arthritis are included in the total population estimates and these differences in disability prevalence, therefore, could be much larger. It is important to note, however, that for tasks such as toileting, dressing, and managing money, estimates of disability for the total U.S. and arthritic U.S. populations are similar. These data suggest that arthritis may be a large contributor to certain types of disability.(ABSTRACT TRUNCATED AT 400 WORDS)