Pay-it-forward gonorrhea and chlamydia testing among men who have sex with men and male STD patients in China: the PIONEER pragmatic, cluster randomized controlled trial protocol.

Background: Gonorrhea and chlamydia are the most common sexually transmitted diseases (STDs) among men who have sex with men (MSM) in China. Previous studies have shown pay-it-forward (PIF) interventions to be associated with a substantial increase in gonorrhea and chlamydia test uptake compared to standard-of-care. We propose a 'pay-it-forward' gonorrhea and chlamydia testing randomized controlled trial (PIONEER).