Introduction. Male-to-Female Gender Identity Disorder (MtF GID) is a complex phenomenon that could be better evaluated by using a dimensional approach.
Aim. To explore the aggregation of clinical manifestations of MtF GID in order to identify meaningful variables describing the heterogeneity of the disorder.
Methods. A consecutive series of 80 MtF GID subjects (mean age 37 ± 10.3 years), referred to the Interdepartmental Center for Assistance Gender Identity Disorder of Florence and to other Italian centers from July 2008 to June 2009, was studied. Diagnosis was based on formal psychiatric classification criteria. Factor analysis was performed.
Main Outcome Measures. Several socio-demographic and clinical parameters were investigated. Patients were asked to complete the Bem Sex Role Inventory (BSRI, a self-rating scale to evaluate gender role) and Symptom Checklist-90 Revised (SCL-90-R, a self-rating scale to measure psychological state).
Results. Factor analysis identified two dimensional factors: Factor 1 was associated with sexual orientation, and Factor 2 related to behavioral and psychological correlates of early GID development. No correlation was observed between the two factors. A positive correlation between Factor 2 and feminine BSRI score was found, along with a negative correlation between Factor 2 and undifferentiated BSRI score. Moreover, a significant association between SCL-90-R Phobic subscale score and Factor 2 was observed. A variety of other socio-demographic parameters and clinical features were associated with both factors.
Conclusions. Behavioral and psychological correlates of Factor 1 (sexual orientation) and Factor 2 (gender identity) do not constitute the framework of two separate clinical entities, but instead represent two dimensions of the complex MtF GID structure, which can be variably intertwined in the same subject. By using factor analysis, we offer a new approach capable of delineating a psychopathological and clinical profile of MtF GID patients. Fisher AD, Bandini E, Ricca V, Ferruccio N, Corona G, Meriggiola MC, Jannini EA, Manieri C, Ristori J, Forti G, Mannucci E, and Maggi M. Dimensional profiles of male to female gender identity disorder: An exploratory research. J Sex Med 2010;7:2487–2498.