JMIR Publications

ABSTRACT

Background:

Models of health behavior hypothesize that knowledge about disease transmission drives behaviors. Several studies conducted in Brazil point to an unfortunate convergence of gay, bisexual and other men who have sex with men (GBM) with low level of HIV knowledge and younger age, lower education, engagement in higher-risk sexual behavior, and never being testing for HIV. Measures to assess level of HIV knowledge have been previously published, including the 12-item HIV/AIDS Knowledge Assessment (HIV-KA) tool. However, measure length can be a barrier to assessment.

Objective:

We started from 12-item HIV-KA tool and developed candidate short forms, evaluated their psychometric properties, and tested the equivalency of their associations with other measures of HIV knowledge.

Methods:

A convenience sample of sexual minorities was recruited during September 2020 to complete a web-based survey through advertisements on two social networking apps (Grindr and Hornet). The survey instrument included items on socio-demographic information, prior HIV testing and HIV test results, PrEP and antiretroviral use, sexual behavior and three HIV knowledge measures. We used exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to assess the factor structure of the of the 12-item HIV-KA. We used optimal test assembly (OTA) methods to develop candidate short forms of the 12-item HIV-KA tool to evaluate them based on prespecified reliability, concurrent validity, and statistically equivalent convergent validity criteria. We used two-sample t-tests to assess post hoc convergent and concurrent validities of the shortened forms.

Results:

Among 2552 sexual and gender minority individuals from Brazil, mean age was 35.1 years, 98% cisgender men and 2% transgender/non-binary, 56% White, and 31% self-reported HIV-positive. CFA indicated a one-factor structure for the 12-item HIV-KA. Concurrent validity correlations were high for all short forms with  6 items, but only versions with  9 items were as reliable as the full-length form and demonstrated equivalency for convergent validity correlations. Confirming post hoc convergent validity, HIV knowledge scores using the 9- and 10-item short forms were significantly different between the groups of participants who perceived U=U slogan as completely accurate vs. not accurate. Confirming post hoc concurrent validity, participants of younger age, of Black, Pardo or Indigenous race, reporting lower education and lower income scored lower on HIV knowledge. Participants who never tested for HIV scored lower than those who tested negative or positive, while those currently using PrEP scored higher than those reporting past or never use.

Conclusions:

OTA methods might be used to shorten the 12-item HIV-KA to 9-item and 10-item versions while maintaining comparable reliability and validity among a large sample of Brazilian sexual minorities. However, these short forms did not shorten sufficiently to justify deviation from full measure.