Association between obsessive-compulsive and related disorders and experiential avoidance: A systematic review and meta-analysis.

The associations between the distinct types of obsessive-compulsive and related disorders and experiential avoidance have received mixed evidence. We, thus, undertook this meta-analysis to i) re-examine the association between obsessive-compulsive disorder and experiential avoidance, ii) extend this association to hoarding disorder, trichotillomania, and body dysmorphic disorder, and iii) identify potential variables affecting these associations. Five databases, including Medline, Embase, PsychINFO, Web of Science and CINAHL, were searched until March 15th, 2021. Meta-analyses based on random-effect models were performed. Heterogeneity and publication bias tests were applied using the I2 statistic and the Egger's test. Meta-regression analyses were performed to identify potential moderators affecting the strength of these associations. Thirty-six unique studies based on n = 11,859 participants were identified. The association between obsessive-compulsive disorder and experiential avoidance was moderate (SMD = 0.75, 95% CI = 0.57-0.92), whereas the associations between individual obsessive-compulsive symptoms, including obsessions, responsibility for harm, ordering, checking, washing and neutralizing, and experiential avoidance ranged from low to strong (SMD ranged between 0.41 and 1.06, 95% CI = 0.25 to 1.40). The associations between hoarding disorder (SMD = 0.93, 95% CI = 0.46-1.40), trichotillomania (SMD = 0.56, 95% CI = 0.48-0.63), body dysmorphic disorder (SMD = 1.55, 95% CI = 0.72-2.37) and experiential avoidance were moderate to strong. Meta-regression analyses demonstrated that studies using the AAQ/AAQ-II scales for measuring experiential avoidance, and/or self-report scales for assessing OCRDs contributed smaller effect sizes. These findings suggest that reducing experiential avoidance may be a viable way of complementing exposure strategies in alleviating obsessive-compulsive and related symptoms.