Introduction: Sexual behaviour among gay and other men who have sex with men (GMSM) is influenced by the shared understanding of HIV/STI risk and peer norms regarding sexual behaviour. However, there is little research evidence to support this relationship. The unique geographic spread of Australian communities, the history of Australian HIV epidemic and the different patterns in risky sexual practices and HIV diagnoses across Australia present an opportunity to explore the role of social norms and GMSM behaviours in shaping different patterns of HIV epidemics. We describe the protocol of the study of contemporary norms in networks and communities of GMSM (CONNECT) which investigates gay community behavioural norms and practices. Methods: CONNECT is aimed to 1) identify the patterns of connections between individuals in GMSM communities and assess how they shape HIV-related behaviours; 2) describe the relationship between social norms and sexual practices; and 3) compare the norms and patterns of behaviour in geographically and epidemiologically distinct GMSM populations in three Australian states New South Wales, Victoria and Western Australia, in order to identify local community norms and barriers to effective HIV prevention. This quantitative cross-sectional study uses respondent-driven sampling (RDS) for recruitment. Results: Analyses will be carried out on individual and community level and will investigate the relationship between community-level behavioural norms and associated practices of individuals. Conclusion: CONNECT is anticipated to inform HIV prevention services to better target and increase the effectiveness of the current health promotion for GMSM in the context of increasing HIV/STI incidence.
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