Table 2.

Sociobehavioral survey domains, descriptions, and measures for the Combination Prevention Effectiveness study for young cisgender men who have sex with men and transgender women, Thailand.

Domain	Description
Sociodemographic	Information collected in this domain includes, but is not limited to, age, education, income, mobility, and insurance status.
PEPa/PrEPb	Information collected in this domain focuses on initial knowledge, awareness, acceptability of and attitudes about PEP/PrEP, and history of use (including recreational use and source of PEP/PrEP).
Sexual risk behavior	Information collected within this domain includes information on number and types of partners (sex work client, nonpaying casual, and stable relationship), frequency and types of sexual acts, condom use during intercourse, and location of the sexual experiences. This includes details on sex work (initiating and stopping), average number of clients per night and week, average number of nights worked per week, and regular/noncommercial sexual partners.
Health care utilization	Information collected in this domain includes information on health care utilization and services to assess engagement at baseline. Information in this domain is also collected at the final visit to assess any supplemental services that have been accessed outside the study.
Engagement in the MSMc, TGWd, and sex work communities	Information collected in this domain includes information on knowledge of and engagement within community forums, PrEP-related contact with outreach workers, social support, connection and collective efficacy within the LGBTe community and in the sex worker community, and perceived support for PrEP and related topics within these communities. Receipt of condoms and contact with outreach workers will also be assessed. This domain allows the team to evaluate the effectiveness of the community mobilization intervention component.
Stigma	Information collected in this domain is focused on self-stigma (internalized homonegativity). This survey domain is adapted from Herek et al [28].
Substance abuse	Information collected in this section includes information on any substances used (amphetamine type substances, alcohol, etc) particularly around sexual experiences and frequency of substance use.
Mental health	The information collected in this section focuses on brief depression, posttraumatic stress disorder, and anxiety screeners using the Substance Abuse/Mental Illness Symptoms Screener [29,30].

^aPEP: postexposure prophylaxis.

^bPrEP: pre-exposure prophylaxis.

^cMSM: men who have sex with men.

^dTGW: transgender women.

^eLGBT: lesbian, gay, bisexual, and transgender.