The effectiveness of financial incentives for health behaviour change: systematic review and meta-analysis

Abstract

Background: Financial incentive interventions have been suggested as one method of promoting healthy behaviour change.

Objectives: To conduct a systematic review of the effectiveness of financial incentive interventions for encouraging healthy behaviour change; to explore whether effects vary according to the type of behaviour incentivised, post-intervention follow-up time, or incentive value.

Data sources: Searches were of relevant electronic databases, research registers, www.google.com, and the reference lists of previous reviews; and requests for information sent to relevant mailing lists.

Eligibility criteria: Controlled evaluations of the effectiveness of financial incentive interventions, compared to no intervention or usual care, to encourage healthy behaviour change, in non-clinical adult populations, living in high-income countries, were included.

Study appraisal and synthesis: The Cochrane Risk of Bias tool was used to assess all included studies. Meta-analysis was used to explore the effect of financial incentive interventions within groups of similar behaviours and overall. Meta-regression was used to determine if effect varied according to post-intervention follow up time, or incentive value.

Results: Seventeen papers reporting on 16 studies on smoking cessation (n = 10), attendance for vaccination or screening (n = 5), and physical activity (n = 1) were included. In meta-analyses, the average effect of incentive interventions was greater than control for short-term (≤ six months) smoking cessation (relative risk (95% confidence intervals): 2.48 (1.77 to 3.46); long-term (>six months) smoking cessation (1.50 (1.05 to 2.14)); attendance for vaccination or screening (1.92 (1.46 to 2.53)); and for all behaviours combined (1.62 (1.38 to 1.91)). There was not convincing evidence that effects were different between different groups of behaviours. Meta-regression found some, limited, evidence that effect sizes decreased as post-intervention follow-up period and incentive value increased. However, the latter effect may be confounded by the former.

Conclusions: The available evidence suggests that financial incentive interventions are more effective than usual care or no intervention for encouraging healthy behaviour change.

Trial registration: PROSPERO CRD42012002393.

Figure 1. Flow diagram of study selection and exclusion.

Figure 2. Risk of bias in included studies.

Figure 3. Meta-analysis of financial incentives for smoking cessation (follow-up ≤six months).

Figure 4. Meta-regression of follow-up period on relative risk, smoking cessation (follow-up

Figure 5. Meta-regression of incentive value on relative risk, smoking cessation (follow-up up

Figure 6. Meta-analysis of financial incentives for smoking cessation (follow-up >six months).

Figure 7. Meta-regression of follow-up period on relative risk, smoking cessation (follow-up >six months).

Figure 8. Meta-regression of incentive value on relative risk, smoking cessation (follow-up of >six months).

Figure 9. Contour enhanced funnel plot, smoking cessation (follow-up ≤six months).

Figure 10. Contour enhanced funnel plot, smoking cessation (follow-up >six months).

Figure 11. Meta-analysis of financial incentives for attendance at vaccination and screening.

Figure 12. Meta-regression of incentive value on relative risk, attendance at vaccination & screening.

Figure 13. Contour enhanced funnel plot, attendance at vaccination and screening.

Figure 14. Meta-analysis of financial incentives for all behaviours (latest follow-up point).

Figure 15. Meta-regression of follow-up point on relative risk, all behaviours (latest follow-up point).

Figure 16. Meta-regression of incentive value on relative risk, all behaviours (latest follow-up point).

Figure 17. Contour enhanced funnel plot, all behaviours (latest follow-up point).