Lesbian, Gay, and Bisexual Identity Scale (LGBIS): construct validation, sensitivity analyses and other psychometric properties

According to Mohr and Fassinger (2006), identity is seen as both self-identification and collective identification with values, beliefs, traits or behaviours and attachments. Their Lesbian, Gay, and Bisexual (LGB) multidimensional identity model accounts for important variables regarding the constitution of identities. This model not only accesses numerous dimensions of the lives of LGB individuals, but is also based on a body of research that recognizes how LGB difficulties are caused by societal intolerance and marginalization (Mohr & Fassinger, 2000). The Lesbian, Gay, and Bisexual Identity Scale (LGBIS; Kendra & Mohr, 2008) constitutes an operationalization of this multidimensional model, and the aim of this article is to present its construct validity by analysing its factor structure using a sample of Portuguese lesbian, gay and bisexual participants. Results from exploratory and confirmatory factor analyses, as well as from factor invariance analysis across sub-samples are presented. In a general way, the factor structure obtained in this study follows the original proposal of Kendra and Mohr's (2008) LGBIS. Moreover, scale sensitivity analyses are presented in order to check for eventual differences in the factor structure and/or factor intercorrelations regarding participant gender and sexual orientation. These results are then discussed in the light of LGB identity models.