title: Who is a community health worker? - a systematic review of definitions.
abstract: Community health workers (CHWs) can play vital roles in increasing coverage of basic health services. However, there is a need for a systematic categorisation of CHWs that will aid common understanding among policy makers, programme planners, and researchers.
  
  
  
  To identify the common themes in the definitions and descriptions of CHWs that will aid delineation within this cadre and distinguish CHWs from other healthcare providers.
  
  
  
  A systematic review of peer-reviewed papers and grey literature.
  
  
  
  We identified 119 papers that provided definitions of CHWs in 25 countries across 7 regions. The review shows CHWs as paraprofessionals or lay individuals with an in-depth understanding of the community culture and language, have received standardised job-related training of a shorter duration than health professionals, and their primary goal is to provide culturally appropriate health services to the community. CHWs can be categorised into three groups by education and pre-service training. These are lay health workers (individuals with little or no formal education who undergo a few days to a few weeks of informal training), level 1 paraprofessionals (individuals with some form of secondary education and subsequent informal training), and level 2 paraprofessionals (individuals with some form of secondary education and subsequent formal training lasting a few months to more than a year). Lay health workers tend to provide basic health services as unpaid volunteers while level 1 paraprofessionals often receive an allowance and level 2 paraprofessionals tend to be salaried.
  
  
  
  This review provides a categorisation of CHWs that may be useful for health policy formulation, programme planning, and research.
authors.affiliation: a Centre for Maternal and Newborn Health , Liverpool School of Tropical Medicine , Liverpool , UK.
authors.forename: Abimbola
authors.initials: A
authors.lastname: Olaniran
authors.affiliation: a Centre for Maternal and Newborn Health , Liverpool School of Tropical Medicine , Liverpool , UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Smith
authors.affiliation: a Centre for Maternal and Newborn Health , Liverpool School of Tropical Medicine , Liverpool , UK.
authors.forename: Regine
authors.initials: R
authors.lastname: Unkels
authors.affiliation: a Centre for Maternal and Newborn Health , Liverpool School of Tropical Medicine , Liverpool , UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Bar-Zeev
authors.affiliation: a Centre for Maternal and Newborn Health , Liverpool School of Tropical Medicine , Liverpool , UK.
authors.forename: Nynke
authors.initials: N
authors.lastname: van den Broek
mesh_terms: D000328:Adult; D003150:Community Health Workers / Q000145:classification*; D005260:Female; D006801:Humans; D007587:Job Description; D008297:Male; D008875:Middle Aged; D009626:Terminology as Topic; D014838:Volunteers / Q000145:classification*
keywords: Lay health worker; health workforce; role; scope of practice