Same but different? Phenomenological differences among various types of body-focused repetitive behaviors.

BACKGROUND: Body-focused repetitive behaviors (BFRBs) are highly prevalent conditions at the border of psychiatry and dermatology. Using a newly developed scale, the Generic BFRB scale (GBS-36), we aimed to compare 4 prominent BFRBs in terms of phenomenology, age at onset, and other illness-related aspects. METHODS: A sample of 391 individuals with different forms of BFRBs completed the GBS-36, the Patient Health Questionnaire-9 (depression), and the World Health Organization Quality of Life-BREF global item (quality of life). RESULTS: Most individuals showed multiple BFRBs (73.9%). Skin picking and nail biting were reported most frequently (nail biting: 68.3%; skin picking: 60.9%; trichotillomania: 52.4%; lip-cheek biting: 31.7%). Nail biting was most common in childhood; the other BFRBs began mainly in adolescence. Both trichotillomania and skin picking were associated with the greatest impairment and urge to perform the behavior. The 2 conditions also showed a higher association with obsessive-compulsive disorder. Overall symptom severity was correlated with earlier age of onset, number of concurrent BFRBs, and severity of depression as well as suicidality. CONCLUSIONS: BFRBs are a heterogeneous group of conditions, with trichotillomania and skin picking showing the largest similarities. Whether the observed differences reflect specific etiological factors awaits further testing.

Self-Help Habit Replacement in Individuals With Body-Focused Repetitive Behaviors: A Proof-of-Concept Randomized Clinical Trial.

Importance: Body-focused repetitive behaviors (BFRBs; eg, skin picking) encompass a set of conditions at the interface of dermatology and psychiatry/psychology. The disorder is prevalent but currently underdiagnosed and undertreated. Objective: To compare a new self-help intervention, habit replacement, against a wait-list control condition for the treatment of BFRBs. Design, Setting, and Participants: This randomized clinical trial was conducted online in 2022. Participants were a population-based nonclinical sample with BFRBs and were recruited via social media. Initially, 481 individuals entered the assessment; 213 were excluded blind to results. A final sample of 268 participants were randomized. The intervention period was 6 weeks. Interventions: Participants were randomized to a self-help intervention, habit replacement, or a wait-list control condition (each n = 134). Main Outcomes and Measures: The Generic BFRB Scale-45 (GBS-45, self-report) represented the primary outcome. Results: Individuals in the 2 conditions (n = 268; 241 [89.9%] women; mean [SD] age, 36.8 [11.1] years; skin picking, 68.3%; trichotillomania, 28.4%; nail biting, 36.6%; lip-cheek biting, 26.1%; other, 20.1%) did not differ on any baseline characteristics. The experimental group significantly improved on the primary outcome (GBS-45) for both the per-protocol (technique was used at least once weekly, ηp2 = 0.068, P = .001) and the intention-to-treat analyses relative to the wait-list control group (expectation-maximization algorithm; ηp2 = 0.019, P = .02). The interaction of group and time yielded statistical trends in favor of the experimental condition only on the Patient Health Questionnaire-9 and quality of life. For the Clinical Global Impressions scale, more individuals in the habit replacement group reported improvement (52.8% vs 19.6%; P < .001). User satisfaction in the habit replacement group was high. Moderation analyses that included all baseline variables showed that those who exhibited nail biting particularly benefited from the new technique. Conclusions and Relevance: The present proof-of-concept randomized clinical trial tentatively demonstrates that habit replacement is a feasible and effective self-help strategy against BFRBs, especially for nail biting. Study limitations include the lack of external assessment and verified diagnoses. In addition, the study is missing follow-up data. Self-help habit replacement shows promise in reducing BFRBs but not concomitant symptoms. Trial Registration: German Clinical Trials Register Identifier: DRKS00030511.