Efficacy of Internet-Delivered Psychodynamic Therapy: Systematic Review and Meta-Analysis.

Recent years have seen an increase of internet-delivered interventions based on psychodynamic treatment models. To test the efficacy of internet-delivered psychodynamic therapy (IPDT), we conducted a systematic review and meta-analysis of randomized controlled trials. Following literature searches, we identified seven studies meeting inclusion criteria. The total number of participants was 528 in the treatment group and 552 in the control conditions. We found small effects favoring IPDT compared to inactive control conditions for main outcomes (g = 0.44), depression (g = 0.46), anxiety (g = 0.20), and quality of life (g = 0.40). There was significant heterogeneity between studies for main outcomes and depression. Within-group effects ranged from Hedges's g = 0.32-0.99. The effects of IPDT were maintained or increased at follow-up. Study quality varied but was generally high. No indications of publication bias were found. In conclusion, IPDT is a promising treatment alternative, especially for depression, although the small number of studies limits the generalizability of the findings.