DOI: 10.6084/m9.figshare.7791455.v1
title: Preferences for HIV testing services among men who have sex with men in the UK: a discrete choice experiment

description: Background: In the UK, approximately 4,200 men who have sex with men (MSM) are living with HIV but remain undiagnosed. Maximising the number of high risk people testing for HIV is key to ensuring prompt treatment and preventing onward infection. This study assessed how different HIV test characteristics affect the choice of testing option, including remote-testing (HIV self-testing or HIV self-sampling) in the UK, a country with universal access to health care. Methods and Findings: Between April and May 2017, a cross-sectional questionnaire based discrete choice experiment (DCE) was conducted in which MSM chose between different hypothetical HIV testing options, including the option not to test. A variety of different testing options were described so that the independent of preference of each defining characteristic could be valued: They included: where each test was taken, the sample method, how the test was obtained, whether infections other than HIV were tested for, test accuracy, the cost of remote-testing, the infection window period and how long it takes to receive a test result. Participants were recruited and completed the instrument online, in order to include those not currently engaged with health care services. The main analysis was conducted using latent class modelling (LCM), with results displayed as odds ratios (ORs) and probabilities. The ORs indicate the strength of preference for one characteristic relative to another (base) characteristic. Six hundred and twenty MSM answered the DCE questions. Most respondents reported they were white (93%) and were MSM (85%). The LCM showed there were two classes within the respondent sample that appeared to have different preferences for the testing options. The first group, that was likely to contain 86% of respondents, had a strong preference for tests by health care professionals (HCPs) compared to remote-testing (OR 6∙4; 95% CI 5∙6, 7∙4) and viewed not-testing as less preferable compared to remote-testing (OR 0∙10; 95% CI 0∙09, 0∙11). In the second group, which was likely to include 14% of participants, not testing was viewed as less desirable than remote-testing (OR 0∙56; 95% CI 0∙53, 0∙59) as were tests by HCPs compared to remote-testing (OR 0∙23; 95% CI 0∙15, 0∙36). In both classes, free remote-tests instead of each costing £30 was the test characteristic with the largest impact on the choice of testing option. Those in class 2 were more likely to have never previously tested and to be non-white than participants in the first group. The main study limitations were that the sample was solely recruited via social media, the study advert was only viewed by people expressing an interest in online material used by MSM and the choices in the experiment were hypothetical rather than observed in the real world. Conclusions: Our results suggest that preferences in the context we examined are broadly dichotomous. One group, containing the majority of MSM, appear comfortable testing for HIV but prefer face-to-face testing by HCPs compared to remote-testing. The other group is much smaller, but contains MSM who are more likely to be at high infection risk. For these people, the availability of remote-testing has the potential to significantly increase net testing rates, particularly if provided for free.