village doctors in Intervention A and B will receive different types of monetary compensation. Doctors in Intervention A will receive standardized compensation for completing their assigned tasks. Doctors in Intervention B will receive performance-based compensation whose amount depends on how well the participants perform on the follow-up questionnaires.

Assess the changes in participants' condom use via the Condoms Use Self-Efficacy Scale (CUSES), a 28-item self-reporting questionnaire using a 5-point scale scoring system in which 0 represents strongly disagree and 4 represents strongly agree.

Assess the severity, frequency and change of participants' substance use via the Drug and Abuse Screening Test (DAST), a 10-item questionnaire with scores range from 0 to 10; 0-2 representing low substance use and 9-10 representing severe substance use.

Will be collecting regional data on HIV prevalence through collaboration with local departments.

Assessed via the use of the Primary Care Evaluation of Mental Disorders (PRIME-MD) patient questionnaire, a self-reporting questionnaire consisting of 26 yes/no questions about the presence of various symptoms of different mental disorders.

Will be collecting regional data on all-cause mortality through collaboration with local departments.

Measured via the use of EQ-5D-3L, a questionnaire comprised of 5 questions and a visual analogue scale to assess the participants' health-related quality of life. Each question has three possible answers corresponding to three levels of perceived problems. Level 1 indicates no problem and level 3 indicates extreme problems. The visual analogue scale is numbered from 0 to 100, with 0 representing "the worst health you can imagine" and 100 representing "the best health you can imagine"

Assessed via the use of the Internalized AIDS-Related Stigma Scale, a 6-item scale that offers a binary (yes/no) response to every item and the scores is computed as the sums of the items with 6 representing high stigmatization and 0 representing low stigmatization.

Assess participants' social support in the community via the use of the Medical Outcomes Study Social Support Survey (MOS-SS), a self-reporting 19-item survey. The mean score of the 19 items will be calculated and transferred onto a 0-100 scale with higher scores indicating more support.

Measured by the HIV Knowledge Questionnaire 18 (HIV-KQ-18). The research team will ask all participants to complete the questionnaire every six months after the intervention period and compare their new scores with their previous score to examine their ability to recall information from the educational modules. The HIV-KQ-18 is a self-administered 18-item questionnaire; the possible scores range from 0 to 18, with 0-9 representing low HIV-related knowledge and 10-18 representing high HIV-related knowledge.

Feasibility of the intervention will be calculated by dividing the number of people who can use WeChat and TikTok by the total number of people living in the area.

Measured by an original engagement and attendance scale. Participants will choose from a range 1 to 6, with 1 representing non-engaging and 6 representing highly engaging.

Assessed via an original 15-item questionnaire with rating scales (6 is Highly Satisfied and 1 is Highly Unsatisfied). Participants will be asked to rate and provide feedback on the intervention's content and method, including the effectiveness of the HIV-related knowledge modules, the time and method of information delivery, village doctors' attitude and competence, the design of the entire experimental intervention process, and more.

Data on the intervention's direct and indirect costs will be collected. Direct cost involves labor costs, research-related travel expenses, and village doctors' and participants' financial compensations. Indirect cost consists of the expenses on cell phone internet data. The date will then be used to evaluate the cost-effectiveness of both interventions.