Compliance with treatment and follow-up protocols in project MATCH: predictors and relationship to outcome.

Treatment and follow-up session attendance data from Project MATCH, a multisite clinical trial investigating patient-treatment matching, were analyzed to study compliance. High rates of compliance to both therapy and research protocols were achieved, enhancing treatment integrity and data quality. Strong baseline predictors of compliance did not emerge, and the small relationships found were consistent with reports from previous studies. Attendance at therapy sessions was moderately correlated with research follow-up participation. Treatment compliance predicted drinking outcome, underscoring the importance of retaining patients in treatment. Future studies should examine the associations between compliance and structural features of the treatment environment, treatment delivery, and context-features that are often under the control of the clinician/investigator.