Table 6 Quality assessment criteria based on the PRISMA Equity Extension checklist reporting on programme theory [1, 5]

1. PRISMA rationale (item 3): Describe assumptions about mechanism(s) by which the intervention is assumed to have an impact on health equity. The review should describe a priori how and why interventions are expected to work and the influence of factors such as setting and participant and programme characteristics

2. Rationale (item 3A): Provide the logic model/analytical framework, if done, to show the pathways through which the intervention is assumed to affect health equity and how it was developed

3. Discussion/conclusions (item 26): Present extent and limits of applicability (what does/does not work) to disadvantaged populations of interest and describe the evidence and logic (how/why) underlying those judgements