Predictors of dropout in self-guided internet-delivered cognitive behaviour therapy for obsessive-compulsive disorder: an exploratory study

Objectives: Self-guided internet-delivered cognitive behaviour therapy (ICBT) is an effective treatment for obsessive-compulsive disorder (OCD); however, there is little research investigating who dropouts of treatment. Therefore, the aim of this study was to conduct an exploratory study of predictors of dropout in self-guided ICBT for OCD. Given that definitions of dropout vary across ICBT studies, we conceptualized dropout in multiple ways: (1) early dropout (proportion of participants who did not complete the pre-treatment questionnaires); (2) proportion of participants who did not commence the intervention; (3) proportion of participants who did not complete the treatment; and (4) proportion of participants who did not complete the post-treatment questionnaires. Method: This was a secondary data analysis of 323 participants with OCD symptoms who provided a successful screening assessment to commence an ICBT intervention. Binary logistic regression was used to predict dropout based on a number of exploratory variables. Results: Early dropout was predicted by the country of the participant (participants in the United Kingdom and India being more likely to dropout), as well as shorter symptom duration (explaining 7% of the variance). Medication use predicted non-completion of the intervention with those taking medication for OCD being less likely to complete the treatment (explaining 3% of the variance). Completion of the post-treatment questionnaires was predicted by higher contamination symptoms, lower depressive symptoms and higher pre-treatment conscientiousness (explaining 13% of the variance). There were no significant predictors of treatment commencement. Conclusions: The study provides important preliminary information concerning which patients with OCD may be more likely to drop out of a self-guided ICBT intervention.