Methods
The MRC Gay Men’s Sexual Health Survey takes place every 3 years and is based on anonymous self-complete questionnaires. Since 2005, the survey has also collected oral fluid specimens using Orasure™ to test anonymously for HIV antibodies. Participants are recruited from commercial gay venues (bars and saunas) in Glasgow and Edinburgh, Scotland's two largetst cities. A form of time and location sampling was used to recruit representative samples of MSM. A team of temporary fieldworkers was trained then employed to distribute and collect questionnaires at two different time points in the early (19.00-21.00) and late evening (21.00-23.00). No bar was visited twice in the same evening. At the end of the survey each bar had been visited at both time points on each day of the week. Each sauna was visited six times over the course of the two week survey period; for a two hour period between 17:00-19:00 on Thursdays and between 14:00-17:00 on Saturdays and Sundays.
Questionnaires include demographics (age, area of residence, employment status, education, frequency of gay scene use), sexual health (HIV/STI testing), and sexual behaviour in the previous 12 months. A measure of higher risk unprotected anal intercourse (UAI) was created and includes men who reported any of the three following behaviours: UAI with 2 or more partners, UAI with casual partners, and/or UAI with unknown/discordant partners in the previous 12 months.
