Do Participants of a Community-based Health Promotion and Disease Self-Management Program Differ from Non-participants?

Generalizability of community-based randomized control trials is an important issue to consider for researchers and policymakers. The purpose of this study is to examine the differences between program participants and non-participants of a community-based health promotion and disease self-management program among Medicare beneficiaries with chronic conditions. We used data from 3402 eligible applications from the Medicare Primary and Consumer-Directed Care Demonstration. We compared individual characteristics (age, gender, Medicaid eligibility, activities of daily living (ADL), instrumental activities of daily living (IADL) and prior use of health service) between participants (n=1605) and non-participants (n=1797). We used descriptive statistics to compare applicants' characteristics and multivariate logistic regression models to identify factors predicting program participation. We found that program participants were slightly younger (p<0.01), less likely to have Medicaid coverage (p<0.01) and have fewer ADL and IADL limitations (p<0.01 for both), less likely to have had a nurse home visit (p<0.01), a home health aide visit (p <0.01), a social worker home visit (p<0.01) during the year prior to eligibility assessment. However, enrolled participants were more likely to have been hospitalized during the same period (p=.05). In addition, earlier applicants were less likely to participate. The results showed that program participants and non-participants were generally similar, with the exception of certain health and prior services use related characteristics. These differences need to be considered so that future community-based intervention studies can be targeted more effectively and enrollment goals can be reached in a timely manner.