Objective: 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.
Results: 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 educa- tion 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.
Conclusions: This review provides a categorisation of CHWs that may be useful for health policy formulation, programme planning, and research.