"Presumed straight until demonstrated otherwise" : the relationships between sexual identity, heteronormativity, sexual identity development and psychological well-being : a thesis in partial fulfilment of the requirements for the degree of Doctorate in Clinical Psychology at Massey University, Palmerston North, New Zealand

Abstract

The conceptualisation and development of a sexual identity has been debated in the literature. Whether identity is conceptualised as categorical or on a continuum, people with same sex experiences, such as those identifying as lesbian, gay, bisexual, questioning and other (LGBQ+), demonstrate lower psychological well-being than their heterosexuallyidentified counterparts. Some have argued this is a result of the stress associated with minority status; others comment on the influence of the development of a sexual identity divergent of the heterosexist norm. Literature supports both claims, yet inconsistencies exist in the study of the psychological outcomes of those with LGBQ+ identities. The current research intended to alleviate some of these debates with three foundational aims: to explore the placement of the sexual identity categories along the continuum, and incorporate more sexual identity categories in sexual identity assessment, demonstrating respect for diversity; to examine the differences in psychological well-being between people with different sexual identities and in different phases of development; and to investigate how dimensions associated with sexual identity, such as identity disclosure, influence these differences. To do this, the study utilized an online survey incorporating a number of measures. People with different sexual identities were significantly different along the sexual identity continuum. In addition, as suspected, non-binary identities (defined in this research as people not ascribing to either heterosexual or lesbian/gay identities) reported lower levels of well-being. When accounting for differences in identityrelated factors, such as identity uncertainty and disclosure, several of the significant differences were eliminated, and all but one of the remaining significant findings demonstrated reduced effect sizes. Those in the Synthesis phase of individual and group identity development generally reported greater levels of psychological well-being. Once again, when controlling for identity-related factors these differences were reduced or eliminated. Future research should investigate a universal model of sexual identity formation, and should assess identity dimensions in those identifying as heterosexual. Gaining greater understandings in the experiences of people with LGBQ+ identities demonstrates areas to target for interventions in order to decrease the disparities which exist between people with these and heterosexual identities.