Do it yourself! Evaluation of self-help habit reversal training versus decoupling in pathological skin picking: A pilot study

Pathological skin picking (PSP) is a rather frequent but yet underrecognized impulse control disorder at the crossroads of dermatology, psychology, and psychiatry. The present pilot study assessed the feasibility and efficacy of self-help interventions in the disorder. Habit reversal training (HRT), the current treatment-of-choice intervention, was tested against a newly developed technique entitled decoupling (DC). Both techniques were conveyed by bibliotherapy. A total of 70 subjects with PSP were recruited via self-help forums and were randomly allocated either to HRT or DC. Manuals were sent via email attachment. Four weeks after the dispatch of the manual, each participant was recontacted and underwent the same questionnaires as before, which included the Modified Skin Picking Scale (M-SPS). Pre-post comparisons indicated a strong symptom decline under HRT but not DC. Every second patient reported a symptom decline due to HRT relative to every third patient in the DC condition (50% versus 33%). The study affirms the efficacy of self-help HRT but discourages the usage of DC in PSP. Possible reasons why DC has exerted positive effects in prior trials on trichotillomania and pathological nail-biting but not PSP are put forward.