Predictors and moderators of treatment response in cognitive behavioural therapy for body dysmorphic disorder: A systematic review

Although Cognitive Behavioural Therapy (CBT) is an effective treatment for Body Dysmorphic Disorder (BDD), substantial variability exists in patient responses. The aim of this systematic review was to synthesise the emerging literature on predictors and moderators of treatment response in CBT for BDD. EMBASE, MEDLINE®, and PsycINFO databases were systematically searched for studies reporting predictor and/or moderator analyses in samples of individuals with diagnosed BDD who received CBT specifically for this disorder. Methodological quality of included studies was assessed using the methodological index for non-randomised studies (MINORS). The search identified eleven studies, examining 56 predictor variables. Nine variables (e.g. insight, depression, BDD severity) emerged as significant predictors in some but not all studies. No variables were found to consistently predict outcome at post-treatment or follow-up. Only one study reported moderator analyses and found no significant effects. In summary, although certain variables, such as insight, depression, and BDD severity, may predict response to CBT for BDD, findings have been inconsistent and common methodological flaws (e.g. inadequate statistical power) reduce the strength of evidence. Further, methodologically-robust research is needed to identify predictors and moderators of responses to CBT for BDD, in order to inform optimisation of CBT and support clinical decision-making.