Abstract
Differentiated care delivery aims to simplify care of people living with HIV, reflect their preferences, reduce burdens on the healthcare system, maintain care quality and preserve resources. However, assessing program effectiveness using observational data is difficult due to confounding by indication and randomized trials may be infeasible. Also, benefits can reach patients directly, through enrollment in the program, and indirectly, by increasing quality of and accessibility to care. Low-risk express care (LREC), the program under evaluation, is a nurse-centered model which assigns patients stable on ART to a nurse every two months and a clinician every third visit, reducing annual clinician visits by two thirds. Study population is comprised of 16,832 subjects from 15 clinics in Kenya. We focus on patient retention in care based on whether the LREC program is available at a clinic and whether the patient is enrolled in LREC. We use G-estimation to assess the effect on retention of two “strategies”: (i) program availability but no enrollment; (ii) enrollment at an available program; versus no program availability. Compared to no availability, LREC results in a non-significant increase in patient retention, among patients not enrolled in the program (indirect effect), while enrollment in LREC is associated with a significant extension of the time retained in care (direct effect). G-estimation provides an analytical framework useful to the assessment of similar programs using observational data.
Funding source: National Institutes of Health
Award Identifier / Grant number: AI069911
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Research ethics: This study was approved by the Moi University Institutional Research Ethics Committee and the Indiana University Institutional Review Board. As data used in this study were obtained as part of routine care, no subject consent was sought or obtained. Data used in the analyses were de-identified per institutional policy prior to transmission and use in the analyses.
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Author contributions: KWK, SK, AS and RK conceptualized and designed and SK, AS and RK oversaw and coordinated the study. BSM performed all processing for the data used in the study. CTY performed all statistical analyses, wrote the analytical software and generated all tables and figures in the paper. CTY, BSM and KWK produced the first draft of the article's text. All co-authors substantially edited and contributed to the final version of the paper. In particular, KWK, SK, AS and RK provided invaluable input about the study and differentiated care practices more generally.
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Competing interests: None.
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Research funding: Funding for the study and the AMPATH program was provided by the United States Agency for International Development (USAID). In addition, CTY, BSM and KWK were supported by NIH grant AI069911 for the East Africa International Epidemiology Databases to Evaluate AIDS (EA-IeDEA) regional consortium.
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Data availability: All data and software (STATA code) are available upon request from the corresponding author.
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