Validation and measurement invariance of a Korean version of the Body Appreciation Scale-2 in cisgender sexual minorities and heterosexual adults

The Body Appreciation Scale-2 (BAS-2) has been validated in various languages across samples with different characteristics. However, its validation and invariance based on sexual orientation in Korean samples have yet to be examined. The current study validated the psychometric properties of the BAS-2 in Korean sexual minorities, and examined measurement invariance between sexual minority and heterosexual individuals and between sexual minority cisgender women and men. Responses from 449 sexual minority and 400 heterosexual individuals were analyzed. In the sexual minority sample, a confirmatory factor analysis supported the scale's unidimensional structure, exhibiting strong factorial validity; further, a correlation analysis revealed positive correlations with body satisfaction, positive sexual minority identity, life satisfaction, and self-esteem, supporting the convergent and criterion-related validity. A hierarchical regression analysis confirmed the incremental validity of the BAS-2 on life satisfaction and self-esteem. The BAS-2 was invariant across women and men at the scalar level in the sexual minority sample, and across sexual minorities and heterosexuals at the partial scalar level in the total sample. Latent mean comparisons indicated no significant differences in BAS-2 scores between sexual minority women and men, while sexual minorities scored significantly lower than heterosexuals. The multiple-indicators multiple-causes model provided evidence of differential item functioning.