Tailored Text Message Prompts to Increase Therapy Homework Adherence: A Single-Case Randomised Controlled Study

Abstract Background: Psychotherapy homework completion is associated with positive treatment outcomes, but many patients show low adherence to prescribed assignments. Whether text-message prompts are effective in increasing adherence to assignments is unknown. Aims: To evaluate whether tailored daily text-message prompts can increase homework adherence in a stress/anxiety treatment. Method: This study used a randomised controlled single-case alternating treatment design with parallel replication in seven participants. Participants received a five-week relaxation program for stress and anxiety with daily exercises. The intervention consisted of daily text messages tailored for each participant. Phases with or without text messages were randomly alternated over the study course. Randomisation tests were used to statistically analyse differences in mean number of completed relaxation exercises between phases. Results: There was a significant (combined p = .018) effect of daily text messages on homework adherence across participants with weak to medium effect size improvements. No negative effects of daily text messages were identified. Conclusions: Tailored text messages can marginally improve adherence to assignments for patients in CBT. Further studies may investigate how text messages can be made relevant for more patients and whether text messages can be used to increase homework quality rather than quantity.