Meta-analysis of dropout from cognitive behavioral therapy: Magnitude, timing, and moderators.

The aim of this study was to answer questions about the rate and timing of dropout from CBT, with specific reference to pretreatment versus during treatment phases. Also explored were several moderators of dropout. METHOD: A meta-analysis was performed on dropout data from 115 primary empirical studies involving 20,995 participants receiving CBT for a range of mental health disorders.

Average weighted dropout rate was 15.9% at pretreatment, and 26.2% during treatment. Dropout was significantly associated with (a) diagnosis, with depression having the highest attrition rate; (b) format of treatment delivery, with e-therapy having the highest rates; (c) treatment setting, with fewer inpatient than outpatient dropouts; and (d) number of sessions, with treatment starters showing significantly reduced dropout as number of sessions increased. Dropout was not significantly associated with client type (adults or adolescents), therapist licensure status, study design (randomized control trial [RCT] vs. non-RCT), or publication recency.