Determinants of Non-Compliance and Attrition in the Elderly

Abstract

This report identifies demographic and health-related baseline factors associated with non-compliance and attrition in elderly subjects participating in a preventive intervention study over a 4-year follow-up period. The Cox proportional hazards model and polychotomous logistic regression were used to evaluate time to clinic assessment non-compliance and type of non-participation. Of 1785 subjects, 35.6% were non-compliant during follow-up which meant they were eligible to participate at the time they were contacted but would not or could not return for an assessment. Refusals due to a lack of continuing interest or being too busy, and those citing health problems constituted the major subgroups of non-compliers. Death, unable to contact, and ineligible due to disenrolment or moving away accounted for nearly 20%. Four-year compliance was achieved by 44.4% of the participants. Time to non-compliance was significantly shorter with older age, lower annual Income, poorer personal health ranking, and, to a marginal extent, depression. Lower annual income was associated with all reasons for non-participation including disenrolment or moving. Other factors correlated with specific types of non-participation. These results can be useful in designing more effective cohort maintenance strategies. Greater resources may be allocated to subgroups who are less likely to continue.