An anonymous, cross-sectional, internet-based survey was carried out to determine the use of barrier protection among WSW. The cohort included an international sample of WSW who were older than 17 years of age and literate in English. Participants were required to identify themselves as WSW; a minimum number of contacts was not set and participants were not required to report whether they were currently involved in a same-sex relationship. An international sample was achieved by advertising the survey at local, national, and international lesbian, gay, bisexual, and transgender community centers; at organizations catering for WSW; and on Facebook (Facebook, Menlo Park, CA, USA). This methodology has been used in prior studies of lesbian sexuality [8
], and details regarding the survey process have been published previously [20
]. Participants were enrolled from January 19 to May 19, 2010. Institutional Review Board approval was obtained from the University of California, San Francisco, USA, before study initiation.
The main outcome variable was the use of barrier protection during various forms of sexual activity. A question was asked regarding frequency (never, less than 25%, 25%–50%, 50%–75%, or 75%–100%) of barrier protection use for various sexual activities. There were specific questions about the use of gloves during digital stimulation of the genitals (giving and receiving), dental dams for oral sex (giving and receiving), and covers/condoms for genital stimulation with sex toys (giving and receiving).
Details of sexual history and ethnodemographic characteristics were obtained, in addition to the sexual health history of participants. Respondents provided their age, geographic location, and race/ ethnicity (African, Asian, Caucasian/white, Latina, Native American, or other). Details were also obtained regarding sexual orientation (homosexual, bisexual, heterosexual “queer,” or other); number of male and female sexual partners in the past 6 months (grouped as 0, 1, or >1 for analysis); sexual relationships with men or women who the participants did not know well (2 separate questions); whether participants had a current regular partner; and type of relationship (single partner/monogamous, primary partner, open relationship, multiple partners, or no current partner). Those in sexual relationships with more than 1 person were specifically asked whether barrier protection was used in the primary relationship and/or with other partners. Information was also obtained regarding history of STIs, including HIV, chlamydia, gonorrhea, herpes, and syphilis.
Descriptive statistics were used to characterize the study population. Simple tabulations were used to study the rates of barrier use for different categories of sexual activity. For simplicity, the frequency of barrier use was grouped into “never,” “less than 75% of the time,” and “75%–100% of the time” for each particular sexual activity assessed. Multivariate analysis was performed using logistic regression including the main exposure variables above P<0.2 from the Wald analysis. Odds ratio (OR) estimates with 95% Wald confidence intervals (CIs) for both the univariate and the multivariate models are reported.
P<0.05 was considered to be statistically significant. Analyses were performed using SAS version 9.2 (SAS Institute, Cary, NC, USA).