A systematic review and meta-analysis of psychiatric treatments for excoriation (skin-picking) disorder

Objective: While individual trials suggest benefit of interventions for excoriation (skin-picking) disorder (ExD), limited systematic evaluation of treatments, or their collective benefit, exists.

Methods: The present study examined the current state of treatments for ExD in a systematic review and meta-analysis and explored potential treatment moderators. Twelve trials were identified for review, including five with a control condition. Of these, nine were eligible to be included in the meta-analysis (three with a control).

Results: A fixed-effects meta-analysis found a large overall treatment effect size (g=1.13), comprised of large effects for behavioral treatments (g=1.19), lamotrigine (g=0.98) and selective serotonin reuptake inhibitors (g=1.09). Clinician-rated measures did not significantly differ from self-rated measures; however, larger effects were observed on self-rated measures of severity, as compared to impairment [Q(1)=4.63, P=.03]. Treatment type, trial length and trial methodological quality were not significant moderators. For controlled trials, the comparative efficacy of treatments for ExD was in the moderate range (g=0.47).

Conclusion: Findings suggest that treatment for ExD has benefit; however, the meta-analysis did not provide strong evidence to support any specific treatment or to suggest its unique clinical benefit over control conditions. Overall, there is a lack of study on treatments for ExD and additional randomized controlled trials with inclusion of multiple informants in assessment is needed.