The delayed, durable effect of expressive writing on depression, anxiety and stress: A meta-analytic review of studies with long-term follow-ups.

BACKGROUND: Expressive writing is a promising tool to heal the wounds with words. AIMS: This meta-analysis evaluated the current state of efficacy of expressive writing on depression, anxiety and stress symptoms among healthy and subclinical samples. MATERIALS AND METHODS: Thirty-one experimental studies (N = 4012) with randomized controlled trials and follow-up assessments were analysed. RESULTS: Results showed that expressive writing had an overall small but significant effect (Hedges' g = -0.12, 95% CI [-0.21, -0.04]) on reducing symptoms of depression, anxiety and stress. Change score analyses suggested that the intervention effect emerged after a delay, as evidenced by assessments at follow-up periods. Moderator analyses indicated that the effect sizes varied as a function of one intervention feature: interval. Studies that implemented short intervals (1-3 days) between writing sessions yielded stronger effects (Gdiff  = -0.18, p = .01) relative to studies that implemented medium intervals (4-7 days) or long intervals (>7 days). The effects of expressive writing remained consistent across other intervention features including focus, instruction, number of sessions, topic repetition and delivery mode. DISCUSSION: Together, these findings provide evidence for the delayed, durable effect of expressive writing and underscore the importance of scheduling writing sessions at short intervals. CONCLUSION: Implications for incorporating expressive writing into clinical practice and daily life are discussed.