VanEpps 2018.

Study characteristics
Methods	Financial incentives for chronic disease management: results and limitations of 2 randomized clinical trials with New York Medicaid patients RCT (NA clusters and NA providers), conducted in 1) Medicaid managed care members, New York, United States of America, 2) The programme included primary care visits and prescription medication and the intervention involved financial incentives through Medicaid. In United States of America. 4 arms: 1. Control (usual care) (control arm) and 2. Intervention (process financial incentives‐earned by attending primary care visits and/or receiving prescription medication refills) (intervention arm), 3. Intervention (outcome financial incentives ‐ earned by reducing glycated haemoglobin levels) (other arm), 4. Intervention (combined financial incentives ‐ combined process and outcome financial incentives) (other arm)
Participants	Control arm N: 256 Intervention arm N: 273, 263, 263 Diabetes type: 2 Mean age: 53 ± NR % Male: 39 Longest follow‐up: 6 months
Interventions	Control arm: (usual care) Intervention arm: (process financial incentives ‐ earned by attending primary care visits and/or receiving prescription medication refills) 1) Financial incentives Intervention arm: (outcome financial incentives ‐ earned by reducing glycated haemoglobin levels) 1) Financial incentives
Outcomes	Glycated haemoglobin
Funding source	The author(s) disclosed receipt of the following financial support for the research, authorship and/or publication of this article: U.S. Department of Health and Human Services, Centers for Medicare and Medicaid Services, 1B1CMS330901
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information
Allocation concealment (selection bias)	Unclear risk	No information
Patient's baseline characteristics (selection bias)	Low risk	See Table 2, P value < 0.05 for race, all others balanced.
Patient's baseline outcomes (selection bias)	Low risk	HbA1C reports are similar between the 4 arms (P value = 0.68), Table 2.
Incomplete outcome data (attrition bias)	High risk	The longitudinal design for both studies resulted in substantial numbers of missing outcome measurements at both 3 months (38% in hypertension study and 40% in diabetes study) and 6 months (43% in hypertension study and 39% in diabetes).
Blinding of participants and personnel (performance bias) and of outcome assessors (detection bias)	Low risk	HbA1C was objectively measured.
Selective reporting (reporting bias)	Unclear risk	No published protocol, but the outcomes in the methods match the results.
Risk of contamination (other bias)	Low risk	Because of the nature of the intervention (financial), it is unlikely that the participants in different arms were contaminated.
Other bias	High risk	No protocol available, however in text (change in eligibility criteria): Initial recruitment procedures targeted only those with poorly controlled hypertension (systolic blood pressure > 140 mm Hg) or poorly controlled diabetes (HbA1c > 8%), but logistical challenges in identifying participants based on these criteria led to a change in recruitment procedures to allow all diagnosed Medicaid patients of the proper age to enrol.