LAUSR

To compare the demographics, sexual risk behaviors, and substance use characteristics of two probability samples of young men who have sex with men (YMSM): one recruited using a geosocial networking application (GSNA) and one recruited using venues. In 2017 and 2018, a cross-sectional online survey was utilized with a sample of 122 YMSM recruited in Los Angeles, CA. Recruitment procedures included both venue-based (n = 68) and GSNA-based probability sampling (n = 54). Sample substance use, sexual risk behaviors (e.g., unprotected sex at last encounter), and demographics were compared using chi-square tests and t-tests. The samples significantly differed in demographics characteristics (e.g., race, education, employment, outness). Samples did not significantly differ in sexual risk variables. Regressions indicated significant differences (higher in the venue sample) in substance use (marijuana, prescription drugs, alcohol, and poppers) between the two samples. Results indicate that recruitment method impacts demographics and substance use prevalence levels for YMSM. GSNA- based recruitment appears to recruit samples from a broader range of social demographics. GSNA-based methods may be especially applicable to areas in which venues are not readily accessible (e.g., rural areas), allowing social research with the most marginalized sexual minority populations.