Methods
We performed a randomized controlled trial on 425 HIV patients in two of the largest HIV clinics in Hanoi, Vietnam. Both the intervention group (238 patients) and the control group (187 patients) received regular consultations with doctors and then participated in 1-month and 3-month follow-up visits. Patients in the intervention group received a theory-driven smartphone app to facilitate medication adherence and self-efficacy in HIV patients. Measurements were developed based on the Health Belief Model, which included the visual analog scale of ART Adherence, HIV Treatment Adherence Self-Efficacy Scale, and HIV Symptom Management Self-Efficacy Scale. We also included the 9-item Patient Health Questionnaire (PHQ-9) to assess patients’ mental health throughout treatment.