title: Impact of Community Health Workers on Use of Healthcare Services in the United States: A Systematic Review.
abstract: BACKGROUND
  As the US transitions to value-based healthcare, physicians and payers are incentivized to change healthcare delivery to improve quality of care while controlling costs. By assisting with the management of common chronic conditions, community health workers (CHWs) may improve healthcare quality, but physicians and payers who are making choices about care delivery also need to understand their effects on healthcare spending.
  
  
  METHODS
  We searched PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, PsycINFO, Embase, and Web of Science from the inception of each database to 22 June 2015. We included US-based studies that evaluated a CHW intervention for patients with at least one chronic health condition and reported cost or healthcare utilization outcomes. We evaluated studies using tools specific to study design.
  
  
  RESULTS
  Our search yielded 2,941 studies after removing duplicates. Thirty-four met inclusion and methodological criteria. Sixteen studies (47%) were randomized controlled trials (RCTs). RCTs typically had less positive outcomes than other study designs. Of the 16 RCTs, 12 reported utilization outcomes, of which 5 showed a significant reduction in one or more of ED visits, hospitalizations and/or urgent care visits. Significant reductions reported in ED visits ranged from 23%-51% and in hospitalizations ranged from 21%-50%, and the one significant reduction in urgent care visits was recorded at 60% (p < 0.05 for all).
  
  
  CONCLUSIONS
  Our results suggest that CHW interventions have variable effects, but some may reduce costs and preventable utilization. These findings suggest that it is possible to achieve reductions in care utilization and cost savings by integrating CHWs into chronic care management. However, variations in cost and utilization outcomes suggest that CHWs alone do not make an intervention successful. The paucity of rigorous studies and heterogeneity of study designs limited conclusions about factors associated with reduced utilization.
authors.affiliation: Center for Primary Care, Harvard Medical School, Boston, MA, USA. Helen_Jack@hms.harvard.edu.|Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, UK. Helen_Jack@hms.harvard.edu.
authors.forename: Helen E
authors.initials: HE
authors.lastname: Jack
authors.affiliation: Center for Primary Care, Harvard Medical School, Boston, MA, USA.
authors.forename: Sophia D
authors.initials: SD
authors.lastname: Arabadjis
authors.affiliation: Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Lucy
authors.initials: L
authors.lastname: Sun
authors.affiliation: Center for Primary Care, Harvard Medical School, Boston, MA, USA.
authors.forename: Erin E
authors.initials: EE
authors.lastname: Sullivan
authors.affiliation: Center for Primary Care, Harvard Medical School, Boston, MA, USA.
authors.forename: Russell S
authors.initials: RS
authors.lastname: Phillips
mesh_terms: D015331:Cohort Studies; D003150:Community Health Workers / Q000191:economics*; D003362:Cost-Benefit Analysis; D003695:Delivery of Health Care / Q000191:economics* / Q000379:methods; D004636:Emergency Service, Hospital / Q000191:economics / Q000706:statistics & numerical data; D006760:Hospitalization / Q000191:economics / Q000706:statistics & numerical data; D006801:Humans; D010043:Outcome and Process Assessment, Health Care / Q000191:economics*; D011787:Quality of Health Care / Q000191:economics; D016032:Randomized Controlled Trials as Topic; D014481:United States
keywords: chronic disease management; community health; community health workers; healthcare costs; healthcare utilization; systematic review