Designing a Community Study of Moderately to Severely Disabled Older Women: The Womenʹs Health and Aging Study

PURPOSE: This paper reports on the design of a community-based study focusing on the effects of prevalent and incident disease and other modifying influences, on changes in functioning among moderately and severely disabled elderly women over a 3-year period [the Womenʹs Health and Aging Study (WHAS)]. METHODS: An approach to conceptualizing and assessing disability which captured functional difficulty across a broad range of activities and tasks was developed, tested on existing national data, and used, in the form of a brief screening instrument, to identify moderately to severely disabled elderly women in a large community sample representative of women 65 and older. Women meeting study criteria were recruited for a baseline interview, a 3-hour in-home clinical exam, as well as follow-up interviews and physical performance tests at 6-month intervals for three years. RESULTS: Prevalence of moderate to severe disability among the screened population proved similar to that expected from analysis of national data (about one-third). The screening interview response rate was 78%, and 71% of women eligible by disability criteria participated. Only women completing both the baseline interview and clinical exam were counted as respondents. Analysis of characteristics of participants and nonparticipants indicated no selection bias related to levels of disability. However, education, race, and age were associated with participation. Women with some college education, black women, and younger women were more likely to participate. CONCLUSIONS: The approach used to identify and recruit moderately to severely disabled elderly women in the WHAS is both feasible and applicable to other community-based research where inclusion of elderly people with moderate to severe disability across several areas of functioning is an objective. Other aspects of study design, such as use of proxy respondents, will also affect recruitment of individuals with impaired functioning into epidemiologic studies.