Measuring participation in an evidence-based practice: illness management and recovery group attendance.

Given the important role of treatment attendance as an indicator of program implementation and as a potential moderator of program effectiveness, this study sought to develop useful indicators of attendance for evidence-based practices. The current study examined consumer attendance patterns in a randomized controlled trial comparing illness management and recovery (n=60) to a problem solving control condition (n=58). Associations were examined between consumer clinical indicators, demographics, and level of recovery and indices of attendance. Attendance was poor, but comparable to rates found in many other studies. Four indicators of attendance (percent sessions attended, time enrolled, periods of attendance, and longest period of attendance) were highly inter-related and were more sensitive to baseline differences than a traditional approach of dichotomizing participants into "attenders" and "non-attenders." Older age, lower hostility, fewer psychotic symptoms, and more education were associated with higher group attendance in both treatment conditions; the client-reported illness management and recovery scale was associated with attendance in the control group. Indicators of attendance were an advancement over dichotomous classification. Strategies to increase attendance are still needed, particularly for younger consumers with greater positive symptoms.