ABSTRACT
Trichotillomania [TTM] is an unknown disorder and resistant to treatment. The purpose of this study was to develop and validate the new metacognitive-cognitive-behavioral model for trichotillomania. The present study was a description and correlation study. In this study, 635 participants [304 male and 331 female] were selected. The participants completed the Massachusetts general hospital hair pulling scale [MGH-HPS], dysfunctional attitude scale [DAS], cognitive distortion scale [CDS], automatic thought questionnaire [ATQ], metacognition questionnaire [MCQ], and the obsessive-compulsive behavior scale [OCBS]. For reliability assessment of the factor structure of the metacognitive-cognitive-behavioral model, the structural equation modeling analysis was used by AMOS software. The results of the structural equation modeling supported a metacognitive-cognitive-behavioral model for trichotillomania. Moreover, the results showed that the model had the best fit to the data and was closely related to the theoretical assumptions. The model presented in this study illustrates a multidimensional approach that focuses on the metacognitive, cognitive, and behavioral dimensions; hence, the model presented in this study is a new explanatory model. This model may prompt future research into trichotillomania and facilitate clinical treatment and case formulation