Open access meta-analysis for psychotherapy research.

Meta-analysis has played a key role in psychotherapy research for nearly 40 years. There is now an opportunity for technology to assist with transparent and open meta-analyses. The authors describe an open-access database of effect sizes and a corresponding web application for performing meta-analyses, viewing the database, and downloading effect sizes. The initial databases provide effect sizes for family therapy for delinquency studies and for alliance-outcome correlations in individual psychotherapy. Disciplinary norms about data sharing and openness are shifting. Furthermore, meta-analyses of behavioral interventions have been criticized for lacking transparency and openness. The database and web application are aimed at facilitating data sharing and improving the transparency of meta-analyses. The authors conclude with a discussion of future directions for the database.