The purpose of this study was to investigate the factor structure, reliability and validity of Gender Identity/Gender Dysphoria Questionnaire in adolescent girls. Using multistage cluster sampling method, 400 female students aged 16-18 years old in Isfahan Secondary School were selected as the sample. Data were collected using Mental Health Questionnaire (Najjarian & Davoodi, 2001), Sexual Identity Questionnaire (Akefi, 2012) and Sexual Discontent and Sexual Identity Scale (Deogracias, 2007). Cronbach's alpha, test-retest reliability, exploratory and confirmatory factor analysis, and concurrent validity were used for data analysis. Reliability of test-retest and internal consistency were 0.93 and 0.92, respectively. The factor structure of gender dissatisfaction and gender identity scale was investigated using both exploratory factor analysis and confirmatory factor analysis. The results of exploratory factor analysis with principal component analysis and varimax rotation indicated that there were four factors in this scale that explained 63.44% of the total variance and the results of confirmatory factor analysis showed four factor model of There is a good fit. Correlation coefficients indicated that concurrent validity of gender dissatisfaction and gender identity scale with other instruments was desirable. The 27-item scale of gender identity/gender dysphoria has good validity.
