Measurement Instruments Assessing Multi-Faceted Stigma Regarding Sexual and Gender Minorities: A Systematic Review of Psychometric Properties.

Stigma against sexual and gender minorities (SGM) populations has serious negative health effects for SGM populations. Despite the growing need for accurate stigma measurement in SGM, there are insufficient valid measurement instruments. Moreover, the lack of consistency in construct usage makes comparisons across studies particularly challenging. A critical review and comparative evaluation of the psychometric properties of the various stigma measures for SGM is necessary to advance our understanding regarding stigma measurement against/among SGMs. Based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a comprehensive search was conducted in 4 bibliographic databases (MEDLINE, PsycINFO, CINAHL, and Web of Science) for empirical articles published from 2010 to 2022 that evaluated the psychometrics properties of measurement instruments assessing stigma against SGMs. The screening, extraction, and scoring of the psychometric properties and methodological quality of selected instruments were performed by following the established standards and COSMIN (Consensus-based Standards for the selection of health Measurement Instruments) checklist, respectively. Of the 2031 studies identified, 19 studies were included that reported psychometric properties of 17 measurement instruments. All instruments, except two, were developed for SGMs (n = 15/17). Most instruments included men who have sex with men (MSM) or gay men (n = 11/15), whereas less than half of the instruments assessed stigma among SGM women (n = 6/15). Internal consistency (Cronbach's alpha) and content validity was reported for all instruments (n = 17); construct and structural validity was also reported for majority of the instruments (n = 15 and 10, respectively). However, test-retest reliability and criterion validity was reported for very few instruments (n = 5 each). Based on the COSMIN checklist, we identified the most psychometrically and methodologically robust instruments for each of the five stigma types: combined stigma, enacted stigma, internalized stigma, intersectional stigma, and perceived stigma. For each stigma type, except anticipated stigma, at least one instrument demonstrated strong promise for use in empirical research; however, the selection of instrument depends on the target population and context of the study. Findings indicated a growing use of instruments assessing multiple stigma types. Future studies need to develop intersectional stigma instruments that account for the multiple and intersecting social identities of SGMs. Additionally, most existing instruments would benefit from further psychometric testing, especially on test-retest reliability, criterion validity, adaptability to different LGBTQIA + populations and cultures.