Acceptance and Commitment Therapy (ACT) has shown promise as a treatment for obsessive-compulsive disorder (OCD) in clinical trials; however, its cross-cultural applicability remains underexplored. This systematic review and meta-analysis assessed ACT's global efficacy across diverse cultural contexts. A comprehensive search of MEDLINE, Scopus, Web of Science, PsycINFO, Google Scholar, and ClinicalTrials.gov identified 468 records, of which nine randomized controlled trials (RCTs) met inclusion criteria. The analysis evaluated ACT's effectiveness in reducing OCD symptoms, with subgroup analyses based on control group type (inactive, pharmacotherapy, psychotherapy) and cultural setting (Western: two studies from the USA and one from Denmark; Eastern: five from Iran, one from South Korea). Results indicated a moderate overall effect size favoring ACT compared to inactive and pharmacotherapy controls, but no significant differences compared to other psychotherapies. While initial cross-cultural comparisons suggested greater effectiveness of ACT in Eastern studies, subsequent sensitivity analyses-including only psychological interventions as comparators- revealed no significant differences in efficacy between Eastern and Western contexts. Although ACT appears to be a culturally adaptable OCD treatment, its evidence base is limited by a shortage of methodologically rigorous RCTs, particularly in Eastern contexts. Additionally, more controlled studies in Western settings are needed to further validate ACT's efficacy and applicability across diverse populations.
Loureiro et al. (2026) studied this question.