How lay health workers tailor in effective health behaviour change interventions: a protocol for a systematic review.

Background: Lay health workers (LHWs) are utilised as a channel of delivery in many health interventions. While they have no formal professional training related to their role, they utilise their connections with the target group or community in order to reach individuals who would not normally readily engage with health services. Lay health worker programmes are often based on psychological theories of behaviour change that point to 'tailoring to individuals' needs or characteristics' as key to success. Although lay health workers have been shown to be effective in many contexts, there is, as yet, little clarity when it comes to how LHWs assess individuals' needs in order to tailor their interventions. This study aims to develop a better understanding of the effective implementation of tailoring in lay health worker interventions by appraising evidence and synthesising studies that report evaluations of tailored interventions.

Method: Health and psychology electronic databases (EMBASE, CINAHL, MEDLINE and PsycINFO) will be searched. Reference lists of included studies will also be searched. For articles that are deemed to be potentially relevant, we will employ a 'cluster searching' technique in order to identify all published papers related to a relevant intervention. Cluster searching will be undertaken in an effort to maximise the breadth and depth of description of the intervention. Quantitative studies will be assessed using the Quality Assessment Tool for Quantitative Studies, developed by the Effective Public Health Practice Project, ON, Canada. Qualitative studies will be assessed using the Critical Appraisal Skills Programme (CASP) checklist for qualitative research. Sythesising the data will enable the development of a taxonomy of strategies for the criteria used for individual assessment of recipients' needs and the ways in which messages or actions are tailored to these individual criteria by LHWs.

Discussion: This systematic review focuses specifically on how health promotion and support is individually tailored in effective programmes by LHWs. This study will be of value to those involved in the design and implementation of interventions that utilise a LHW.

Systematic Review Registration: PROSPERO CRD42015030071.