OBJECTIVES: Uncertainty remains about whether personal financial incentives could achieve sustained changes in health-related behaviours that would reduce the fast-growing global non-communicable disease burden. This review aims to estimate whether: i. financial incentives achieve sustained changes in smoking, eating, alcohol consumption and physical activity; ii. effectiveness is modified by (a) the target behaviour, (b) incentive value and attainment certainty, (c) recipients' deprivation level.
METHODS: Multiple sources were searched for trials offering adults financial incentives and assessing outcomes relating to pre-specified behaviours at a minimum of six months from baseline. Analyses included random-effects meta-analyses and meta-regressions grouped by timed endpoints.
RESULTS: Of 24,265 unique identified articles, 34 were included in the analysis. Financial incentives increased behaviour-change, with effects sustained until 18months from baseline (OR: 1.53, 95% CI 1.05-2.23) and three months post-incentive removal (OR: 2.11, 95% CI 1.21-3.67). High deprivation increased incentive effects (OR: 2.17; 95% CI 1.22-3.85), but only at >6-12months from baseline. Other assessed variables did not independently modify effects at any time-point.
CONCLUSIONS: Personal financial incentives can change habitual health-related behaviours and help reduce health inequalities. However, their role in reducing disease burden is potentially limited given current evidence that effects dissipate beyond three months post-incentive removal.