Sexual minority (e.g., gay, lesbian, bisexual) people are at increased risk for suicidal thoughts and behaviors compared to their heterosexual peers. The interpersonal theory of suicide proposes that perceived burdensomeness and thwarted belongingness are central to the desire to die, and both are associated with suicidal ideation in sexual minority samples. The Interpersonal Needs Questionnaire (INQ) was developed to measure these risk factors and has become the most commonly used measure. However, it is unknown whether the INQ demonstrates similar measurement properties across subgroups of sexual minority people. Therefore, the goal of this study was to examine whether the 15-item version of the INQ exhibited measurement invariance (MI) across sexual orientation (gay/lesbian vs. bi+), gender identity (cisgender men vs. cisgender women vs. transgender/gender diverse individuals), and race/ethnicity (non-Latinx White individuals vs. people of color) in a sample of 792 sexual minority young adults (ages 18-29). A series of multigroup measurement invariance models indicated that the INQ-15 met strict invariance (i.e., equal factor loadings, item intercepts, and residual variances) across all three dimensions of identity. This indicates that it can be used and compared across diverse samples of sexual minority young adults. Results also indicated that perceived burdensomeness was greater for transgender/gender diverse individuals than for cisgender men and women, and that perceived burdensomeness and thwarted belongingness were greater for people of color than for non-Latinx White individuals. In contrast, gay/lesbian and bi+ individuals did not differ. Additional research is needed to understand the factors that account for these group differences.
Public Significance StatementThis study demonstrated that the psychometric properties of the Interpersonal Needs Questionnaire (INQ-15) do not differ across sexual orientation, gender identity, and race/ethnicity groups in a sample of sexual minority young adults. Therefore, the INQ-15 can be used with confidence with diverse samples of sexual minority young adults.