RT Journal Article SR Electronic T1 Understanding for whom, why and in what circumstances payment for performance works in low and middle income countries: protocol for a realist review JF BMJ Global Health FD BMJ Publishing Group Ltd SP e000695 DO 10.1136/bmjgh-2017-000695 VO 3 IS 3 A1 Borghi, Josephine A1 Singh, Neha S A1 Brown, Garrett A1 Anselmi, Laura A1 Kristensen, Soren YR 2018 UL http://gh.bmj.com/content/3/3/e000695.abstract AB Background Many low and middle income countries (LMIC) are implementing payment for performance (P4P) schemes to strengthen health systems and make progress towards universal health coverage. A number of systematic reviews have considered P4P effectiveness but did not explore how P4P works in different settings to improve outcomes or shed light on pathways or mechanisms of programme effect. This research will undertake a realist review to investigate how, why and in what circumstances P4P leads to intended and unintended outcomes in LMIC.Methods Our search was guided by an initial programme theory of mechanisms and involved a systematic search of Medline, Embase, Popline, Business Source Premier, Emerald Insight and EconLit databases for studies on P4P and health in LMIC. Inclusion and exclusion criteria identify literature that is relevant to the initial programme theory and the research questions underpinning the review. Retained evidence will be used to test, revise or refine the programme theory and identify knowledge gaps. The evidence will be interrogated by examining the relationship between context, mechanisms and intended and unintended outcomes to establish what works for who, in which contexts and why.Discussion By synthesising current knowledge on how P4P affects health systems to produce outcomes in different contexts and to what extent the programme design affects this, we will inform more effective P4P programmes to strengthen health systems and achieve sustainable service delivery and health impacts.