Study setting and sample size
The study is taking place in a single center, the HIV integrated clinic Cipto Mangunkusumo Hospital, Jakarta. All patients receive government free antiretroviral program according to Indonesian guidelines. The first-line regimen consists of two nucleoside reverse transciptase inhibitors (NRTIs) and one non-nucleoside reverse transcriptase inhibitor (NNRTI), and the second-line regimen of two NRTIs and one protease inhibitor (PI). The majority of patients belong to urban and mainly low- to middle-income families living in Jakarta. Assuming that the effect size is 0.1, standard deviation is 0.12, and the use of 2 sample t-test, the sample size needed for 90% power and 5% significant level is 32 per arm. With an additional 20% drop out rate, each arm (placebo and control group) will need 40 participants.