Table 1. Inclusion and exclusion criteria.

SPIDER element	Include	Exclude
Sample	Facility-based HCWs Community-based health workers Health managers, policymakers and stakeholders across the health system	Exclude if others included and lumped alongside these in findings.
Phenomenon of interest	Quality improvement (not just quality of care or general health systems capacity or situation assessment) Quality includes safety, effectiveness, patient-centeredness, timeliness, efficiency, equity in health uptake/access, utilization, or outcomes. Must be primary care or primary health care oriented, reported separately from tertiary and referral level.	Exclude high income country context, exclude health technology assessments, exclude other systematic and umbrella reviews. Also exclude very low-quality studies (judged by consensus) and those from tertiary care (university/teaching and research hospitals). Exclude editorials and opinion pieces, economic evaluations, and clinical case reports. Include only primary empirical research (mixed or qualitative) reporting enablers to and barriers of quality improvement from perspective of health workers, health managers or regulators as study participants.
Design	Mixed methods and Qualitative designs. Mixed methods papers have qualitative data detailing enablers or barriers.	Quantitative design with no discernible data on contextual drivers of QI measured or reported
Evaluation	Intervention to improve quality of health care i.e., efforts introduced to Change quality from level X to Y or measured from time X to time Y i.e., a QI initiative rather than just a measurement of quality of care.	Economic evaluations with no accompanying contextual data One-off measurement seeking to perceptions of stakeholders on quality of care rather than on QI intervention/initiative/ project
Research type	Qualitative data reported separate from quantitative findings in mixed methods. Qualitative research findings qualitatively reported (not quantified in percentages or numerical values). Semi-structured or in-depth Interviews, focus groups, observation, ethnography etc.	Surveys, Randomized Trials with no process evaluations reporting barriers or enablers of QI initiative or QI project