Study title

Abstract copyright UK Data Service and data collection copyright owner.The SIGMA project research had its origins in 1982 at University College Cardiff, as a project to investigate gay and bisexual men's sexual behaviour as AIDS began to threaten (then GRID: gay-related immune deficiency). Following extensive piloting, the main SIGMA study was launched in 1986 and between 1987 and 1994 carried out a seven-year, five-phase cohort study of gay and bisexual men. The main aims of the study were to estimate, in a natural (non-clinic based) sample: (1) the prevalence and incidence of sexual behaviours (especially those implicated in the transmission of HIV), (2) to take blood-samples to investigate rates of HIV sero-positivity and sero-conversion, (3) to examine the social and sexual lifestyles and culture of gay and bisexual men, and (4) to monitor the trends towards safer sex practice, especially the adoption of condoms. As a longitudinal study, there was a major focus on change in these processes. SIGMA was one of the largest studies of gay and bisexual men in the world, was an integral part of the WHO (Global Programme on AIDS) Seven-Nation Homosexual Response Studies and shared research instruments with a number of US and European projects. A component part of SIGMA data consists of 1,975 month-long sexual diaries. The Diaries Project asked gay and bisexual men to keep diaries, filled in on a daily basis usually over a period of a maximum of one month, giving detailed information about the content and sequence of their sexual activity, about their partners' characteristics and about the context in which the sexual behaviour occurred. Diarists were recruited both as part of the Project SIGMA ongoing samples, supplemented occasionally by large-scale appeals in the gay press for volunteers. The 774 diaries have now been anonymised, microfiched and indexed. the machine-readable coded versions are lodged in this dataset. The natural-language microfiched and...