Estimation of the population size of gay, bisexual and other men who have sex with men in Canada, 2020

Abstract

Gay-identifying, bisexual-identifying (GB) and other men who have sex with men (MSM), both an identity-and behaviourally-based community, account for approximately half of new HIV diagnoses in Canada, despite representing only 3-4% of the adult male population. 1 Reliable population size estimates of this community are necessary to allocate resources to meet prevention needs and for modelling the HIV epidemic. 2 A nuanced understanding of the epidemic among gay, bisexual and other men who have sex with men has been limited by the challenges estimating this population size: lack of population sample frame, 3 small sample size, stigma surrounding sexual orientation disclosure, 4 and inconsistent measurement of sexual orientation. 5 Previous Canadian estimates were solely identity-based, which did not account for gay/bisexual-identifying men not willing to reveal sexual orientation on a government survey or non-identifying men who also engaging in sex with other men.