Effectiveness of Peer Support Programs for Severe Mental Illness: A Systematic Review and Meta-Analysis

(1) Background: While medication and various forms of psychotherapy are common treatments for severe mental illness, peer support programs have also proven to be effective in managing mental disorders. These programs, which involve individuals with similar experiences in navigating mental health challenges, aim to improve coping skills and foster supportive community networks. However, despite the prevalent mention of peer support programs, especially those with supervision, there has been no systematic review or meta-analysis of peer support supervision. This study aimed to systematically review and meta-analyze the forms and effectiveness of peer support programs for individuals with severe mental illnesses. (2) Methods: A literature search focusing on randomized controlled trials (RCTs) published between February 2003 and January 2024 was conducted. (3) Results: Sixteen RCTs meeting the inclusion criteria and involving a total of 4008 participants were reviewed. These studies utilized various peer support program strategies, with eight studies included in the qualitative analysis. The combined effect sizes for depressive symptoms (d = 0.12; 95% CI, -0.14, 0.37; p = 0.37), empowerment (d = 1.17; 95% CI, -0.81, 3.15; p = 0.25), quality of life (d = 0.70; 95% CI, -0.12, 1.52; p = 0.09), psychiatric symptoms (d = -0.05; 95% CI, -0.20, 0.10; p = 0.54), and self-efficacy (d = 0.20; 95% CI, 0.05, 0.36; p = 0.01) were assessed. (4) Conclusions: Our analysis emphasizes the need for further studies on peer support programs for individuals with severe mental illness, particularly those focused on self-efficacy outcomes across diverse geographic locations involving more countries and with larger scales to bolster the strength of the evidence.