What the strongest evidence shows: CHWs can improve health outcomes and reduce gaps
The single most compelling finding comes from a large, population-based study in Michigan involving over 125,000 mother-infant pairs. Participation in a CHW home visiting program (Strong Beginnings) was associated with a 2.2% reduction in preterm birth and a 0.8% reduction in very low birth weight among Medicaid-insured individuals, with even greater risk reductions among Black participants [2]. This means that for every 100 women in the program, about 2 fewer had a baby born too early, directly narrowing a well-known racial disparity.
A randomized clinical trial in Philadelphia tested a CHW intervention that connected primary care, home, and school for Black children with asthma. Before the COVID-19 pandemic disrupted the study, children receiving the combined clinic-school CHW intervention had a statistically significant improvement in asthma control scores compared to controls [1]. This suggests that when CHWs coordinate care across all the places a child lives and learns, they can reduce the severe asthma disparities that Black children face.
Where CHW programs fall short: reach doesn't always mean equity
A large systematic review of 167 studies across 33 low- and middle-income countries found that while CHW programs successfully reach many marginalized groups, health inequalities often persist in the populations they serve [5]. The review identified that disadvantaged groups still face barriers to taking up CHW health advice and referrals, meaning that simply deploying CHWs does not automatically close gaps. The authors argue that CHW programs must be designed with explicit equity strategies, fair working conditions, and advocacy opportunities to truly reduce disparities.
Even in well-designed trials, results can be mixed. The Philadelphia asthma study found that while all groups improved, the primary analysis showed no clinically meaningful difference between CHW and control groups over 12 months [1]. Only when the researchers looked at the pre-pandemic period—when the intervention was delivered as intended—did they see a clear benefit. This highlights that CHW effectiveness depends on program fidelity, funding stability, and the broader context.
Are CHW programs worth the investment? The evidence says yes, especially for chronic disease
A cost-effectiveness study of a nurse practitioner/CHW team for cardiovascular disease risk reduction found that the incremental cost per patient was only $627, and the program produced meaningful improvements in blood pressure, cholesterol, and blood sugar [4]. For example, every 1% drop in systolic blood pressure cost just $157, making it a cost-effective approach for community health centers serving high-risk populations.
In Uganda, using CHWs to track immunization defaulters led to a 35% increase in BCG vaccine coverage and an 18% increase in DTP3 coverage compared to control facilities [3]. The program also proved feasible: CHWs registered more children than the official district estimate, showing they can improve data quality and reach underserved families. This demonstrates that CHW programs can be both effective and practical in resource-limited settings.
About These Sources
This answer is built on 5 peer-reviewed studies — published from 2015 to 2024, 1 from 2024 or later, 3 in Q1 journals, collectively cited 216 times — selected as the most relevant from 10 studies that passed quality screening, drawn from 72 papers retrieved from a database of over 500 million.
Sources used in this answer
Community Health Workers Linking Clinics and Schools and Asthma Control
In a randomized clinical trial of 626 Black children with asthma, a CHW intervention linking clinics, homes, and schools improved asthma control before pandemic disruptions, but the primary analysis over 12 months showed no clinically meaningful difference between groups.
Community Health Worker Home Visiting, Birth Outcomes, Maternal Care, and Disparities Among Birthing Individuals With Medicaid Insurance
In a retrospective cohort study of over 125,000 Medicaid-insured mother-infant pairs, participation in a CHW home visiting program was associated with a 2.2% reduction in preterm birth and a 0.8% reduction in very low birth weight, with greater reductions among Black individuals.
Engagement of community health workers to improve immunization coverage through addressing inequities and enhancing data quality and use is a feasible and effective approach: An implementation study in Uganda
In an implementation study in Uganda, using CHWs to track immunization defaulters led to a 35% increase in BCG vaccine coverage and an 18% increase in DTP3 coverage compared to control facilities.
Cost-effectiveness of nurse practitioner/community health worker care to reduce cardiovascular health disparities.
A cost-effectiveness analysis of a nurse practitioner/CHW team for cardiovascular risk reduction found an incremental cost of $627 per patient, with cost-effectiveness ratios of $157 per 1% drop in systolic blood pressure and $40 per 1% drop in LDL cholesterol.
Community health workers and health equity in low- and middle-income countries: systematic review and recommendations for policy and practice
A systematic review of 167 studies across 33 low- and middle-income countries found that CHW programs reach many marginalized groups but health inequalities often persist, with disadvantaged groups facing barriers to taking up CHW advice and referrals.