Effectiveness, barriers, and facilitators of interventions delivered by traditional healers for the treatment of common mental disorders: A systematic review

We investigated the effectiveness of interventions provided by traditional healers for common mental disorders (CMDs) together with associated barriers and facilitators. Electronic databases including MEDLINE, APA Psych Info, Allied and Complementary Medicine, Embase, CINAHL, Social Science Citation Index, and Scopus were searched from inception until October 2021. Randomised controlled trials (RCTs) assessing interventions by traditional healers for CMDs and qualitative and mixed-methods studies examining traditional healers and their attendees' views about the treatment of CMDs by traditional healers were included. Cochrane Risk of Bias Assessment tool (RoB-1) and Critical Appraisal Skills Programme (CASP) were used for the quality assessment of studies. A meta-analysis and thematic synthesis were conducted. Sixteen RCTs (1,132 participants) and 17 qualitative or mixed-methods studies (380 participants) were included. Improvement in symptoms was greater for interventions by traditional healers compared to control groups for both depression and anxiety. Subgroup analyses indicated that only "spiritual passe" interventions showed improvement in depression and anxiety, and participants with co-morbid anxiety and physical conditions showed improvement in anxiety. Facilitators to engaging with interventions by traditional healers were shared faith-based worldview exhibited by traditional healers and their attendees and perceived effectiveness of traditional healing. Stigma and concealing mental illness were found to be barriers not only to formal healthcare but also to traditional healers' services. Interventions by traditional healers such as "spiritual passe" are effective in improving CMDs. However, evidence is still limited due to the low quality of studies and lack of long-term evidence.