Table 1.

Description of quarterly and semiannual study visits for the Combination Prevention Effectiveness Study for cisgender men who have sex with men and transgender women, Thailand.

Study visit	Description
Quarterly study visits (every 3 months)	Confirm participant contact and locator information Administer CASIa behavioral questionnaire Assess participant experience and impacts of study participation (including adverse events and social harms) Screen for signs and symptoms of acute HIV infection Provide HIV testing (including pooled NAATb testing if the participant has symptoms of acute HIV infection) Collect DBSc for storage Distribute condom and lubricant
Semiannual study visits (every 6 months)	All procedures conducted at quarterly study visits Syphilis testing Rectal swab collection for rectal gonorrhea and chlamydia testing Serum creatinine measurement and estimated creatinine clearance calculation (for participants on PrEPd)

^aCASI: computer-assisted self-interview.

^bNAAT: nucleic acid amplification test.

^cDBS: dried blood spots.

^dPrEP: pre-exposure prophylaxis.