Basinga 2011.

Methods	Parallel‐arm cluster‐RCT conducted at 166 sites in Rwanda between June 2006 and Oct 2006.
Participants	Sample size: 166 clusters (2563 women). Clusters: districts without pre‐existing P4P schemes managed by non‐governmental organisations. Individuals: not described.
Interventions	Target: health system (financial intervention). Arm 1 (80 clusters, 1242 women): P4P scheme to supplement primary health centres’ input‐based budgets. In this P4P scheme, payments are made directly to facilities and are used at each facility’s discretion. Arm 2 (86 clusters, 1321 women): control facilities would continue to receive traditional input‐based financing for an additional 23 months until the rollout of the scheme was complete.
Outcomes	Trial primary outcomes: prenatal care visits and institutional deliveries. Review outcomes reported: Primary: ANC coverage (at least 4 visits). Secondary: ANC coverage (at least 1 visit), health facility deliveries, tetanus protection, use of child preventative care. Follow‐up: baseline and 25 months.
Notes	Funders: World Bank’s Bank‐Netherlands Partnership Program, the British Economic and Social Research Council, the Government of Rwanda, and the World Bank’s Spanish Impact Evaluation Fund; Global Development Network and the MacNamara Foundation.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"The remaining districts were then grouped into eight blocks based on rainfall, population density, and livelihood data from the 2002 Census.15 Blocks covered between two and 4 districts, depending on district characteristics and size. The blocks were then divided into two sides, and one side of each block was randomly assigned to either the intervention or control group. Randomisation was done by coin toss."
Allocation concealment (selection bias)	Unclear risk	Not reported.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Women interviewed in households would not have been aware of their local facility's group assignment. Women attending facilities should also not have been aware of the funding scheme in operation at her local health clinic.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All surveys were done by trained enumerators hired by external firms specialised in data collection who were masked to whether they were interviewing in an intervention or control area."
Recruitment bias (for cluster RCTs)	Low risk	None noted.
Incomplete outcome data (attrition bias) All outcomes	Low risk	2.1 % of intervention and 1.9% of control households refused to participate. 12% loss to follow‐up between baseline and end of trial surveys. 11.8% attrition in each treatment arm between first and second interviews. Incomplete household surveys were dropped from the sample after each round.
Selective reporting (reporting bias)	Low risk	Most relevant outcomes are reported.
Analysis bias	Unclear risk	Analysis appropriate for clusters, ICC and ITT not reported.
Other bias	High risk	Allocation assignment not respected due to government restructuring.
Overall risk assessment	Unclear risk	Due to uncertainties raised above.