Financial Incentives, Income Supplementation, Cash Transfer, and Universal Basic Income Interventions in Diabetes: Understanding Differences and Effectiveness: A Scoping Review.

The objective of this review is to evaluate and summarize the evidence base for the effects of monetary intervention approaches (the use of positive monetary reinforcers and gains) on diabetes outcomes. A reproducible search using OVID Medline, PubMed, Scopus, and CINAHL was conducted. Articles published from database creation up to July 2024 were searched. Outcomes included hemoglobin A1c (HbA1c), LDL, BMI, blood pressure, quality of life (QOL), psychosocial factors, self-care behaviors, and diabetes complications. A total of 13 articles met inclusion criteria and were included for final synthesis. Looking at the monetary approach across each study, eight used financial incentives, three used a form of income supplementation, one used cash transfers, and one used a combination of income supplementation and financial incentives. Ten of the 13 studies found statistically significant and clinically meaningful changes in HbA1c. For participants receiving interventions, change in HbA1c ranged from 0.19% to 1.74% for interventions incorporating financial incentives, 0.7% to 1.3% for interventions incorporating income supplementation, and 0.2% to 0.7% for the study incorporating cash transfers. Overall, evidence supports the relationship between monetary approaches, diabetes-related outcomes, and self-care behaviors across monetary approaches. Future studies should consider comparison between different monetary approaches using designs that will allow identification of effective strategies. As these approaches are theoretically and structurally different, pathways identifying the underlying mechanisms of change are greatly needed to advance the field.