Table 1.

Eligibility Criteria

Studies were included if they met the following PICOS criteria:
Patients	• Have at least one chronic disease • Adults or children
Intervention	• CHWs must play a primary role in the intervention, with CHW defined as individuals who work primarily in a health-related role, have no professional or paraprofessional training in healthcare or social work, and were selected for their role largely because of their familiarity with a community or population (consistent with the Massachusetts Department of Public Health and American Public Health Association definitions of CHWs)1 , 23 • Other health professionals or community workers may participate in the intervention, as long as CHWs play the main role • CHWs are paid for their work • CHWs manage a condition that is relevant to primary care and not typically handled by specialists (such as cancer treatment navigation) • The intervention does not primarily address a public health concern, such as vaccination for an entire community • The intervention does not primarily address maternal and infant health or screening, as these are not relevant to chronic disease management
Comparison	• Cohort, pre-post, or randomized controlled trial design
Outcome	• Report on healthcare costs or utilization, including ED visits, urgent care visits, primary care visits, or medication use* • Quantitative outcome
Setting	• United States • Not at a worksite

*We included adherence to medication as an outcome because medications contribute to healthcare costs, both in the short term (potential increase) and long term (potential decrease). For example, asthma, a condition that CHWs commonly treat, have medications that are used only or more often if the disease is poorly controlled (rescue inhalers), making medication a form of preventable utilization