Preferences of men who have sex with men for performing anal self-examination for the detection of anal syphilis in Australia: A discrete choice experiment

BACKGROUND: Regular anal self-examination could potentially reduce syphilis transmission by detecting anal syphilis earlier among men who have sex with men (MSM). This study aimed to examine the preferences of MSM on performing anal self-examination to detect anal syphilis. METHODS: An online survey with a discrete choice experiment (DCE) was distributed to MSM attending a sexual health clinic and through social media in Australia between June and November 2020. The DCE examined the preferred attributes of anal self-examination that would encourage MSM to perform anal self-examination. Data were analysed using a random parameters logit (RPL) model. FINDINGS: The median age of 557 MSM who completed the survey was 35 (inter quartile range, 27-45). The choice to perform anal self-examination was most influenced by two attributes: the accuracy of anal self-examination to diagnose anal syphilis, and the frequency of anal self-examination, followed by the type of instruction materials to perform anal self-examination, waiting time for medical review, and type of support received if abnormalities were found. Using the most preferred attributes, 98% of people would conduct anal self-examination compared with 35% when the least preferred anal self-examination attributes were offered. INTERPRETATION: If anal self-examination were recommended for anal syphilis screening, it will be important to consider preferences of MSM: men were more likely to undertake anal self-examination if the frequency was once a month and there was higher accuracy of detecting anal syphilis. FUNDING: Australian National Health And Medical Research Council.