ffects of integrated models of care for diabetes and hypertension in low-income and middle-income countries: a systematic review and meta-analysis

Tackling syndemics by integrating infectious and noncommunicable diseases in health systems of low- and middle-income countries: A narrative systematic review

The co-occurrence of infectious diseases (ID) and non-communicable diseases (NCD) is widespread, presenting health service delivery challenges especially in low-and middle-income countries (LMICs). Integrated health care is a possible solution but may require a paradigm shift to be successfully implemented. This literature review identifies integrated care examples among selected ID and NCD dyads. We searched PubMed, PsycINFO, Cochrane Library, CINAHL, Web of Science, EMBASE, Global Health Database, and selected clinical trials registries. Eligible studies were published between 2010 and December 2022, available in English, and report health service delivery programs or policies for the selected disease dyads in LMICs. We identified 111 studies that met the inclusion criteria, including 56 on tuberculosis and diabetes integration, 46 on health system adaptations to treat COVID-19 and cardiometabolic diseases, and 9 on COVID-19, diabetes, and tuberculosis screening. Prior to the COVID-19 pandemic, most studies on diabetes-tuberculosis integration focused on clinical service delivery screening. By far the most reported health system outcomes across all studies related to health service delivery (n = 72), and 19 addressed health workforce. Outcomes related to health information systems (n = 5), leadership and governance (n = 3), health financing (n = 2), and essential medicines (n = 4)) were sparse. Telemedicine service delivery was the most common adaptation described in studies on COVID-19 and either cardiometabolic diseases or diabetes and tuberculosis. ID-NCD integration is being explored by health systems to deal with increasingly complex health needs, including comorbidities. High excess mortality from COVID-19 associated with NCD-related comorbidity prompted calls for more integrated ID-NCD surveillance and solutions. Evidence of clinical integration of health service delivery and workforce has grown-especially for HIV and NCDs-but other health system building blocks, particularly access to essential medicines, health financing, and leadership and governance, remain in disease silos.

Interventions in adult patients with multimorbidity in low-income and middle-income countries: protocol for a mixed-methods systematic review

INTRODUCTION

Multimorbidity, the coexistence of two or more chronic conditions in the same individual, is a major public health problem in low-income and middle-income countries (LMICs). The use of single-disease guidelines contributes to polypharmacy, fragmented care and increased treatment burden. Health systems in LMICs are very different from those in high-income countries, and adapting interventions from one to the other may not be feasible. This review aims to systematically present the current evidence for interventions for multimorbidity in the LMIC setting.

METHODS AND ANALYSIS

In this mixed-methods systematic review, we will include all studies of interventions for the care of adults (>18 years of age) with multimorbidity (defined as the presence of two or more chronic illnesses in an individual) in any healthcare organisation (primary, secondary or tertiary care) in an LMIC (as defined by the World Bank), published between 2000 and March 2023. All primary study designs will be included. Studies reported in languages other than English and those describing interventions classified as 'financial' or 'governance arrangement' according to the Cochrane Effective Practice and Organisation of Care classification will be excluded. MEDLINE, PubMed, Cochrane Library, TRIP, SCOPUS and the 3ie databases will be searched. The titles will be screened by one author, and two authors will independently screen all included abstracts and full texts. A third author will resolve conflicts at every stage. Studies will be reviewed for quality of evidence using appropriate tools. Epidemiological, intervention and outcome data will be extracted and summarised. Outcomes of interest for LMICs defined by the Global Alliance for Chronic Diseases research group will be analysed. Subgroup analysis according to study types and study settings will be done.

ETHICS AND DISSEMINATION

No ethics approval is required for this systematic review. Results will be disseminated through publication in an open-access journal and presentation at conferences.

PROSPERO REGISTRATION NUMBER

CRD42023391897.

What is meant by 'integrated personalized diabetes management': A view into the future and what success should look like

Integrated personalized diabetes management (IPDM) has emerged as a promising approach to improving outcomes in patients with diabetes mellitus (DM). This care approach emphasizes the integration and coordination of different providers, including physicians, nurses, dietitians, social workers and pharmacists. The goal of IPDM is to provide patients with personalized care that is tailored to their needs. This review addresses the concept of integrated care and the use of technology (including data, software applications and artificial intelligence) as well as managerial, regulatory and financial aspects. The implementation and upscaling of digitally enabled IPDM are discussed, with elaboration of successful practices and related evidence. Finally, recommendations are made. It is concluded that the adoption of digitally enabled IPDM on a global level is inevitable, considering the challenges created by an increasing prevalence of patients with DM and the need for better outcomes and improvement of health system sustainability.

Gaussian process emulation to improve efficiency of computationally intensive multidisease models: a practical tutorial with adaptable R code

BACKGROUND

The rapidly growing burden of non-communicable diseases (NCDs) among people living with HIV in sub-Saharan Africa (SSA) has expanded the number of multidisease models predicting future care needs and health system priorities. Usefulness of these models depends on their ability to replicate real-life data and be readily understood and applied by public health decision-makers; yet existing simulation models of HIV comorbidities are computationally expensive and require large numbers of parameters and long run times, which hinders their utility in resource-constrained settings.

METHODS

We present a novel, user-friendly emulator that can efficiently approximate complex simulators of long-term HIV and NCD outcomes in Africa. We describe how to implement the emulator via a tutorial based on publicly available data from Kenya. Emulator parameters relating to incidence and prevalence of HIV, hypertension and depression were derived from our own agent-based simulation model and other published literature. Gaussian processes were used to fit the emulator to simulator estimates, assuming presence of noise for design points. Bayesian posterior predictive checks and leave-one-out cross validation confirmed the emulator's descriptive accuracy.

RESULTS

In this example, our emulator resulted in a 13-fold (95% Confidence Interval (CI): 8-22) improvement in computing time compared to that of more complex chronic disease simulation models. One emulator run took 3.00 seconds (95% CI: 1.65-5.28) on a 64-bit operating system laptop with 8.00 gigabytes (GB) of Random Access Memory (RAM), compared to > 11 hours for 1000 simulator runs on a high-performance computing cluster with 1500 GBs of RAM. Pareto k estimates were < 0.70 for all emulations, which demonstrates sufficient predictive accuracy of the emulator.

CONCLUSIONS

The emulator presented in this tutorial offers a practical and flexible modelling tool that can help inform health policy-making in countries with a generalized HIV epidemic and growing NCD burden. Future emulator applications could be used to forecast the changing burden of HIV, hypertension and depression over an extended (> 10 year) period, estimate longer-term prevalence of other co-occurring conditions (e.g., postpartum depression among women living with HIV), and project the impact of nationally-prioritized interventions such as national health insurance schemes and differentiated care models.

Models of integrated care for multi-morbidity assessed in systematic reviews: a scoping review

BACKGROUND

The prevalence of multi-morbidity is increasing globally. Integrated models of care present a potential intervention to improve patient and health system outcomes. However, the intervention components and concepts within different models of care vary widely and their effectiveness remains unclear. We aimed to describe and map the definitions, characteristics, components, and reported effects of integrated models of care in systematic reviews (SRs).

METHODS

We conducted a scoping review of SRs according to pre-specified methods (PROSPERO 2019 CRD42019119265). Eligible SRs assessed integrated models of care at primary health care level for adults and children with multi-morbidity. We searched in PubMed (MEDLINE), Embase, Cochrane Database of Systematic Reviews, Epistemonikos, and Health Systems Evidence up to 3 May 2022. Two authors independently assessed eligibility of SRs and extracted data. We identified and described common components of integrated care across SRs. We extracted findings of the SRs as presented in the conclusions and reported on these verbatim.

RESULTS

We included 22 SRs, examining data from randomised controlled trials and observational studies conducted across the world. Definitions and descriptions of models of integrated care varied considerably. However, across SRs, we identified and described six common components of integrated care: (1) chronic conditions addressed, (2) where services were provided, (3) the type of services provided, (4) healthcare professionals involved in care, (5) coordination and organisation of care and (6) patient involvement in care. We observed differences in the components of integrated care according to the income setting of the included studies. Some SRs reported that integrated care was beneficial for health and process outcomes, while others found no difference in effect when comparing integrated care to other models of care.

CONCLUSIONS

Integrated models of care were heterogeneous within and across SRs. Information that allows the identification of effective components of integrated care was lacking. Detailed, standardised and transparent reporting of the intervention components and their effectiveness on health and process outcomes is needed.

Person-centred, integrated non-communicable disease and HIV decentralized drug distribution in Eswatini and South Africa: outcomes and challenges

INTRODUCTION

Non-communicable diseases (NCDs) are highly prevalent in people living with HIV above 50 years of age and account for increasing mortality. There is little published evidence supporting person-centred, integrated models of HIV care, hypertension and diabetes treatment in southern Africa, and no data demonstrating mortality reduction. Where clinical visits for NCDs and HIV cannot be combined, integrated medication delivery presents an opportunity to streamline care and reduce patient costs. We present experiences of integrated HIV and NCD medication delivery in Eswatini and South Africa, focusing on programme successes and implementation challenges. Programmatic data from Eswatini's Community Health Commodities Distribution (CHCD) from April 2020 to December 2021 and South Africa's Central Chronic Medicines Dispensing and Distribution (CCMDD) from January 2016 to December 2021 were provided by programme managers and are summarized here.

DISCUSSION

Launched in 2020, Eswatini's CHCD provides over 28,000 people with and without HIV with integrated services, including HIV testing, CD4 cell count testing, antiretroviral therapy refills, viral load monitoring and pre-exposure prophylaxis alongside NCD services, including blood pressure and glucose monitoring and hypertension and diabetes medication refills.  Communities designate neighbourhood care points and central gathering places for person-centred medication dispensing.  This programme reported fewer missed medication refill appointments among clients in community settings compared to facility-based settings. South Africa's CCMDD utilizes decentralized drug distribution to provide medications for over 2.9 million people, including those living with HIV, hypertension and diabetes.  CCMDD incorporates community-based pickup points, facility "fast lanes" and adherence clubs with public sector health facilities and private sector medication collection units.  There are no out-of-pocket payments for medications or testing commodities.  Wait-times for medication refills are lower at CCMDD sites than facility-based sites.  Innovations to reduce stigma include uniformly labelled medication packages for NCD and HIV medications.

CONCLUSIONS

Eswatini and South Africa demonstrate person-centred models for HIV and NCD integration through decentralized drug distribution. This approach adapts medication delivery to serve individual needs and decongest centralized health facilities while efficiently delivering NCD care.  To bolster programme uptake, additional reporting of integrated decentralized drug distribution models should include HIV and NCD outcomes and mortality trends.

Effectiveness of integrated chronic care models for cardiometabolic multimorbidity in sub-Saharan Africa: a systematic review and meta-analysis

OBJECTIVES

This review aimed at identifying the elements of integrated care models for cardiometabolic multimorbidity in sub-Saharan Africa (SSA) and their effects on clinical or mental health outcomes including systolic blood pressure (SBP), blood sugar, depression scores and other patient-reported outcomes such as quality of life and medication adherence.

DESIGN

Systematic review and meta-analysis using the Grading of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

DATA SOURCES

We systematically searched PubMed, Embase, Scopus, Web of Science, Global Health CINAHL, African Journals Online, Informit, PsycINFO, ClinicalTrials.gov, Pan African Clinical Trials Registry and grey literature from OpenSIGLE for studies published between 1999 and 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included randomised controlled trial studies featuring integrated care models with two or more elements of Wagner's chronic care model.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers used standardised methods to search and screen included studies. Publication bias was assessed using the Doi plot and Luis Furuya Kanamori Index. Meta-analysis was conducted using random effects models.

RESULTS

In all, we included 10 randomised controlled trials from 11 publications with 4864 participants from six SSA countries (South Africa, Kenya, Nigeria, Eswatini, Ghana and Uganda). The overall quality of evidence based on GRADE criteria was moderate. A random-effects meta-analysis of six studies involving 1754 participants shows that integrated compared with standard care conferred a moderately lower mean SBP (mean difference=-4.85 mm Hg, 95% CI -7.37 to -2.34) for people with cardiometabolic multimorbidity; Hedges' g effect size (g=-0.25, (-0.39 to -0.11). However, integrated care compared with usual care showed mixed results for glycated haemoglobin, depression, medication adherence and quality of life.

CONCLUSION

Integrated care improved SBP among patients living with cardiometabolic multimorbidity in SSA. More studies on integrated care are required to improve the evidence pool on chronic care models for multimorbidity in SSA. These include implementation studies and cost-effectiveness studies.

PROSPERO REGISTRATION NUMBER

CRD42020187756.

Implementation considerations for non-communicable disease-related integration in primary health care: a rapid review of qualitative evidence

BACKGROUND

Integrated delivery of primary health care (PHC) services is a health reform recommended for achieving ambitious targets of the Sustainable Development Goals and Universal Health Coverage, responding to growing challenges of managing non-communicable and multimorbidity. However, more evidence is needed on effective implementation of PHC integration in different country settings.

OBJECTIVE

This rapid review synthesized qualitative evidence on implementation factors affecting integration of non-communicable disease (NCD) into PHC, from the perspective of implementers. The review contributes evidence to inform the World Health Organizations' guidance on integration of NCD control and prevention to strengthen health systems.

METHOD

The review was guided by standard methods for conducting rapid systematic reviews. Data analysis was guided by the SURE and WHO health system building blocks frameworks. We used Confidence in the Evidence of Reviews of Qualitative Research (GRADE-CERQual) to assess the confidence of the main findings.

RESULTS

The review identified 81 records eligible for inclusion, from 595 records screened. We sampled 20 studies for analysis (including 3 from expert recommendations). Studies covered a wide range of countries (27 countries from 6 continents), the majority from low-and middle-income countries (LMICs), with a diverse set of NCD-related PHC integration combinations and implementation strategies. The main findings were categorised into three overarching themes and several sub-themes. These are, A: Policy alignment and governance, B: Health systems readiness, intervention compatibility and leadership, and C: Human resource management, development, and support. The three overarching findings were assessed as each having a moderate level of confidence.

CONCLUSION

The review findings present insights on how health workers responses may be shaped by the complex interaction of individual, social, and organizational factors that may be specific to the context of the intervention, the importance of cross-cutting influences such as policy alignment, supportive leadership and health systems constraints, knowledge that can inform the development of future implementation strategies and implementation research.

Six-month blood pressure and glucose control among HIV-infected adults with elevated blood pressure and hyperglycemia in northern Tanzania: A prospective observational study

BACKGROUND

People with HIV in sub-Saharan Africa are increasingly developing age-related comorbidities. The purpose of this prospective observational study was to describe 6-month outcomes among Tanzanians with HIV and elevated blood pressure or hyperglycemia under current care pathways.

METHODS

Adults presenting for routine HIV care were enrolled and underwent blood pressure and blood glucose measurements. Participants with abnormal blood pressure or glucose were referred for further care, as per current guidelines. Participants' blood pressure and point-of-care glucose were re-evaluated during their 6-month follow-up visit. Elevated blood pressure was defined as systolic ≥140 mmHg or diastolic ≥90 mmHg. Hyperglycemia was defined as fasting glucose ≥126 mg/dl or random glucose ≥200 mg/dl. An electrocardiogram was obtained at enrollment and at follow-up. Interim myocardial infarction and interim myocardial ischemia were defined as new pathologic Q waves and new T-wave inversions, respectively.

RESULTS

Of 500 participants, 155 had elevated blood pressure and 17 had hyperglycemia at enrolment. At 6-month follow-up, 7 (4.6%) of 155 participants with elevated blood pressure reported current use of an anti-hypertensive medication, 100 (66.2%) had persistent elevated blood pressure, 12 (7.9%) developed interim myocardial infarction, and 13 (8.6%) developed interim myocardial ischemia. Among 17 participants with hyperglycemia, 9 (56%) had persistent hyperglycemia at 6 months and 2 (12.5%) reported current use of an anti-hyperglycemic medication.

CONCLUSIONS

Interventions are needed to improve non-communicable disease care pathways among Tanzanians with HIV.

Integrating community-based HIV and non-communicable disease care with microfinance groups: a feasibility study in Western Kenya

BACKGROUND

The Harambee study is a cluster randomized trial in Western Kenya that tests the effect, mechanisms, and cost-effectiveness of integrating community-based HIV and non-communicable disease care within microfinance groups on chronic disease treatment outcomes. This paper documents the stages of our feasibility study conducted in preparation for the Harambee trial, which include (1) characterizing the target population and gauging recruitment capacity, (2) determining community acceptability of the integrated intervention and study procedures, and (3) identifying key implementation considerations prior to study start.

METHODS

Feasibility research took place between November 2019 and February 2020 in Western Kenya. Mixed methods data collection included surveys administered to 115 leaders of 105 community-based microfinance groups, 7 in-person meetings and two workshops with stakeholders from multiple sectors of the health system, and ascertainment of field notes and geographic coordinates for group meeting locations and HIV healthcare facilities. Quantitative survey data were analyzed using STATA IC/13. Longitude and latitude coordinates were mapped to county boundaries using Esri ArcMap. Qualitative data obtained from stakeholder meetings and field notes were analyzed thematically.

RESULTS

Of the 105 surveyed microfinance groups, 77 met eligibility criteria. Eligible groups had been in existence from 6 months to 18 years and had an average of 22 members. The majority (64%) of groups had at least one member who owned a smartphone. The definition of "active" membership and model of saving and lending differed across groups. Stakeholders perceived the community-based intervention and trial procedures to be acceptable given the minimal risks to participants and the potential to improve HIV treatment outcomes while facilitating care integration. Potential challenges identified by stakeholders included possible conflicts between the trial and existing community-based interventions, fear of group disintegration prior to trial end, clinicians' inability to draw blood for viral load testing in the community, and deviations from standard care protocols.

CONCLUSIONS

This study revealed that it was feasible to recruit the number of microfinance groups necessary to ensure that our clinical trial was sufficient powered. Elicitation of stakeholder feedback confirmed that the planned intervention was largely acceptable and was critical to identifying challenges prior to implementation.

TRIAL REGISTRATION

The original trial was prospectively registered with ClinicalTrials.gov (NCT04417127) on 4 June 2020.

Evidence-based guidelines for hypertension and diabetes in sub-Saharan Africa: a scoping review

OBJECTIVE

The Collaboration for Evidence-Based Healthcare and Public Health in sub-Saharan Africa (CEBHA+), a research network, aims to build capacities for evidence-based healthcare. Hypertension (HTN) and diabetes mellitus (DM) are two priority areas of the network, both are major causes of burden of disease in this region. This review aimed to: (1) identify existing evidence-based guidelines for HTN and DM, (2) map their recommendations and (3) assess their quality.

SETTING

Sub-Saharan Africa.

DESIGN

Scoping review.

METHODS

Systematic searches for evidence-based guidelines, developed with systematic review of evidence and certainty of evidence assessment, were undertaken in electronic databases and grey literature, and ministries of health of all countries in this region were contacted. Included guidelines were assessed with the Appraisal of Guidelines for research and evaluation II (AGREE-II) tool. Searches were conducted between 7 December 2021 and 14 January 2022. Results are presented descriptively.

RESULTS

66 potentially relevant guidelines were identified, developed in 23, out of 49 sub-Saharan African countries. Of these, only two guidelines (on DM) reported the use of systematic review of evidence and certainty of evidence assessment. Their quality appraisal showed that both have relatively similar scores on domains of AGREE-II, with higher scores on Scope and Purpose and Clarity and Presentation domains, and lower on Stakeholder Involvement, Applicability, Rigour of Development and Editorial independence domains. The overall scores of both guidelines were 50% and 58%, respectively.

CONCLUSIONS

Less than half of the countries in sub-Saharan Africa developed and published their own guidelines for HTN or DM. The quality appraisal showed that the two included guidelines scored relatively low in several crucial domains of AGREE-II. Countries in this region could consider adopting or adapting already published high-quality recommendations, in order to facilitate a more efficient and faster development of much needed trustworthy evidence-based guidance.

Mapping national, regional and local prevalence of hypertension and diabetes in Ethiopia using geospatial analysis

OBJECTIVES

This study aimed to map the national, regional and local prevalence of hypertension and diabetes in Ethiopia.

DESIGN AND SETTING

Nationwide cross-sectional survey in Ethiopia combined with georeferenced ecological level data from publicly available sources.

PARTICIPANTS

9801 participants aged between 15 and 69 years.

PRIMARY OUTCOME MEASURES

Prevalence of hypertension and diabetes were collected using the WHO's STEPS survey approach. Bayesian model-based geostatistical techniques were used to estimate hypertension and diabetes prevalence at national, regional and pixel levels (1×1 km²) with corresponding 95% credible intervals (95% CrIs).

RESULTS

The national prevalence was 19.2% (95% CI: 18.4 to 20.0) for hypertension and 2.8% (95% CI: 2.4 to 3.1) for diabetes. Substantial variation was observed in the prevalence of these diseases at subnational levels, with the highest prevalence of hypertension observed in Addis Ababa (30.6%) and diabetes in Somali region (8.7%). Spatial overlap of high hypertension and diabetes prevalence was observed in some regions such as the Southern Nations, Nationalities and People's region and Addis Ababa. Population density (number of people/km²) was positively associated with the prevalence of hypertension (β: 0.015; 95% CrI: 0.003-0.027) and diabetes (β: 0.046; 95% CrI: 0.020-0.069); whereas altitude in kilometres was negatively associated with the prevalence of diabetes (β: -0.374; 95% CrI: -0.711 to -0.044).

CONCLUSIONS

Spatial clustering of hypertension and diabetes was observed at subnational and local levels in Ethiopia, which was significantly associated with population density and altitude. The variation at the subnational level illustrates the need to include environmental drivers in future NCDs burden estimation. Thus, targeted and integrated interventions in high-risk areas might reduce the burden of hypertension and diabetes in Ethiopia.

Integrated approach for noncommunicable disease management in the Americas

An overview of an integrated approach to improve noncommunicable disease (NCD) management is presented, along with tools on integrating NCD management as part of health system strengthening in the Americas. The study is based on an analysis of Pan American Health Organization/World Health Organization (PAHO/WHO) data and publicly available information on NCD care and capacity, disruptions in NCD services, and guidance on NCD management. Gaps in NCD care are highlighted, in which an estimated 43.0% of men and 28.0% of women with hypertension in Latin America remain undiagnosed; and for those with diabetes, 32.8% in Central and South America are undiagnosed. Yet, only 17/35 countries (49%) in the Americas report having evidence-based national guidelines for NCD management through a primary care approach and only 7/35 countries (20%) report provision of drug therapy, including glycaemic control for eligible persons. To improve NCD management, an integrated approach is needed to coordinate and deliver care across the levels of the health system. This includes increasing primary care capacity and competencies to address multiple chronic conditions, and integration with other complementary programs to avoid missing opportunities for NCD diagnosis and management. An integrated approach to NCD management, and implementation of available tools, should be part of rebuilding health systems after the COVID-19 pandemic.

Implementing screening for hypertension in archetypal HIV primary care: a mixed-methods assessment

BACKGROUND

High prevalence of HIV and hypertension in sub-Saharan Africa puts adults living with HIV (ALWH) at high risk of end-organ complications. Both World Health Organization (WHO) and national guidelines recommend screening and treatment of hypertension among ALWH on antiretroviral therapy (ART). We evaluated the implementation of hypertension screening among adults on ART at three Uganda Cares Primary care facilities.

METHODS

Using a sequential explanatory mixed-methods approach, we reviewed patient records, and interviewed both patients and providers during 2018 and 2019. We obtained demographics, clinical and blood pressure (BP) measurements via records review. We estimate the period prevalence of screening and use adjusted modified Poisson regression models to evaluate predictors of screening. In-depth interviews were analysed using a thematic approach to explain the observed prevalence and predictors of BP screening.

RESULTS

Records for 1426 ALWH were reviewed. Patients had a median age of 35 years and 65% of them were female. Most were on ART (89% on first-line) with a median duration of 4 years. Only 262 (18%) were overweight or obese with a body mass index (BMI) > 25 Kg/M². In 2017 or 2018 patients made a median of 3 visits and 783 patients had a BP recorded, hence a period prevalence 55%. Older age, male sex, more clinic visits, and clinic site were associated with screening in the adjusted analyses. Erratic BP screening was corroborated by patients' and providers' interviews. Challenges included; high patient numbers, low staffing, provider apathy, no access to treatment, and lack of functioning of BP equipment.

CONCLUSION

Almost half of regular HIV clinic attendees at these prototypical primary care HIV clinics were not screened for hypertension for a whole year. Improving BP screening requires attention to address modifiable challenges and ensure local buy-in beyond just providing equipment.

Future directions for HIV service delivery research: Research gaps identified through WHO guideline development

Nathan Ford and co-authors discuss the systematic identification of research gaps in improving HIV service delivery.