Sexual risk and HIV-testing behaviour by gay and bisexual men in Canada.

Behavioural epidemiology is an important aspect of HIV research, particularly among marginalized populations where measurement of rates of infection have not been conducted. This Canadian study provides a country-wide analysis of the characteristics and behaviours of gay and bisexual men, and examines the influence of geographic, socio-demographic and lifestyle influences on sexual behaviour and test-seeking. A purposive sample of 4,803 men was recruited through gay-identified venues. In order to provide national representation seven sampling strata were defined. Data were collected by self-completed questionnaire. A three-level hierarchical logistic regression analysis is used to model two behaviours, unprotected anal intercourse and test-seeking. The results showed that, nationally, 22.9% of respondents reported at least one episode of unprotected anal intercourse in the previous 3 months, and 63% had been tested. Characteristics and behaviours of men varied across the country. Geographic differences appear to be less important in explaining unprotected anal intercourse than test-seeking. In conclusion, policy, programmes and social environment appear to exert an important influence on test-seeking, whereas cultural and psychosocial dimensions appear to have a greater influence on sexual behaviour.