Testing the Tripartite Influence Model among heterosexual, bisexual, and lesbian women.

• The Tripartite Influence Model is supported among bisexual and lesbian women. • Bisexual women may experience more peer appearance pressures than lesbian women. • Thin-ideal internalization may be particularly harmful for bisexual women. This cross-sectional study explored similarities and differences between heterosexual, bisexual, and lesbian women in levels of, and relationships between, the following constructs using a Tripartite Influence Model framework: family, peer, and media appearance pressures, thin- and muscular-ideal internalization, and eating disorder (ED) pathology. Self-identified heterosexual (n = 1,528), bisexual (n = 89), and lesbian (n = 278) undergraduate women completed the Sociocultural Attitudes Towards Appearance Questionnaire-4 and the Eating Disorder Examination-Questionnaire. Sexual orientation differences in appearance pressures, appearance-ideal internalization, and ED pathology were examined via analysis of variance tests. Relationships between these variables were examined with multi-group path analyses, controlling for age, race/ethnicity, and body mass index. Compared with lesbian women, heterosexual and bisexual women reported higher levels of peer appearance pressures. Paths from peer appearance pressures and thin-ideal internalization to shape/weight overvaluation and body dissatisfaction were strongest for bisexual women. Overall, results indicate notable similarities between heterosexual, bisexual, and lesbian women. However, preliminary evidence for potential differences highlights the importance of examining variation in ED risk between sexual minority subgroups. [ABSTRACT FROM AUTHOR]