Study design and setting
This cross-sectional study used the anonymized data collected in 2021 as part of a baseline survey of a quasi-experimental study implemented by Khmer HIV/AIDS NGO Alliance (KHANA), a leading non-governmental organization working on HIV and AIDS in Cambodia [22]. The parent study aimed to assess the feasibility and effectiveness of the Community-based ART Delivery (CAD) model compared to the current standard care model, the Multi-Month Dispensing (MMD) model. CAD was carried out by a group of stable people living with HIV, where the collection of ART was performed by a group leader whenever they visited the ART clinic for medical appointments and clinical follow-ups. The medications were distributed during the monthly community meetings, where the members of the community ART group would interact with their peers for medical, social, and emotional support.
A list of participating ART clinics was developed after consulting the Database Management Unit of the National Centre for HIV/AIDS, Dermatology, and STD (NCHADS) and other partners involved in the HIV program implementation. Twenty ART clinics in ten provinces (10 clinics for intervention and 10 for the control arm) were chosen for the quasi-experimental study. The selection of the clinics was based on the availability of the implementing partners and the number of stable people living with HIV eligible for enrolment.
Variables and measurements
There is no standard method for measuring ART adherence [24]. The World Health Organization (WHO) recommends a multi-method approach be used to measure adherence levels [25]. In this study, we employed self-reporting adherence questions, the Visual Analogue Scale (VAS), and the knowledge of pill identification test to assess adherence [26]. Each adherence method was calculated separately before combining them to determine the adherence level.
The self-reporting method has been consistently associated with clinical outcomes and is widely used for its low cost and ease of implementation [27, 28]. Self-reporting adherence questions require participants to answer if they had missed any medications in the past two months, the reason for missing them, any recent missing doses, and their perception of their health status after taking them [26] The questionnaire included seven questions, and the participants would be considered “good adherent” if they answered “no” to all questions and “moderately or poorly adherent” if they answered “yes” to any of the questions.
VAS questions asked participants to recall if they had missed any dose over the past four days with a percentage adherence scale. Participants with a result above 95% would be considered adherent, while those who scored 95% and below would be considered non-adherent [29].
For the knowledge of pill identification test, participants were asked to show their medication and if they could remember the dosage, the frequency, prescribed timing, and other additional instructions. Only participants who followed the prescription as intended would be considered adherent.
Sociodemographic characteristics included age group, sex, marital status, employment, monthly income, and formal education level. HIV treatment history and health status information included ART treatment duration, transportation mode, relationship and satisfaction with healthcare services, and comorbidities of other chronic diseases such as diabetes, elevated cholesterol, and hypertension.
The psychosocial elements included depressive symptoms, quality of life (QoL), stigma and discrimination, perceived self-efficacy, and social support. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale (CES-D-10), a 10-item four-point Likert scale questionnaire assessing depressive symptoms. A cut-off score of 10 or higher suggests significant depressive symptoms [30, 31]. The 12-item Short Form Survey (SF-12) was used to assess health-related QoL, where two 0-100 component scores, physical (PCS) and mental (MCS), were generated. A score of 50 or less on the PCS indicates a physical condition, and a score of 42 or less on the MCS indicates clinical depression [32–34].
The People Living with HIV Stigma Index was used to measure HIV stigma and discrimination experiences due to having HIV over the past 12 months [35–37]. The questionnaire has three main sections: (1) experiences of stigma and discrimination in various settings such as home, community, workplace, and religious settings; (2) internal stigma; and (3) fear of stigma and discrimination from family and communities. The total score was calculated in each section, and the mean score of each section was used to divide the participants into two groups, one with lower and another with higher HIV stigma and discrimination [35].
Self-efficacy was measured by the Perceived Self-Efficacy for Receiving Antiretroviral Therapy Scale (PSEARTS), which assessed the participant’s confidence in carrying out health-related behaviors [38, 39]. PSEARTS has five components: (1) self-efficacy in health responsibility to maintain life, (2) self-efficacy in physical activities for life, (3) self-efficacy in nutrition for life, (4) self-efficacy in spiritual growth for life, and (5) self-efficacy in stress management for life. The questionnaire is a four-point Likert scale based on confidence levels (no, low, high, and very high confidence). The participants were then categorized into poor (no/low confidence) and strong self-efficacy (high and very high confidence).
Social support was assessed by the Berlin Social Support Scale (BSSS), a 4-point Likert scale questionnaire. The total possible scores were 12–60, with a higher score indicating better perceived social support. The scores were further categorized into low (12–27 scores), moderate (28–44), and high (45–60) perceived social support [40–42].