Applying economic evaluation to public health interventions: the case of interventions to promote physical activity

BACKGROUND This paper explores the application of alternative approaches to economic evaluation of public health interventions, using a worked example of exercise referral schemes (ERSs). METHODS Cost-utility (CUA) and cost-consequence analyses (CCA) were used to assess the cost-effectiveness of ERSs. For the CUA, evidence was synthesized using a decision analytic model that adopts a lifetime horizon and NHS/Personal Social Services perspective. Outcomes were expressed as incremental cost per quality-adjusted life-year (QALY). CCA was conducted from a partial-societal perspective, including health and non-healthcare costs and benefits. Outcomes were reported in natural units, such as cases of strokes or CHD avoided. RESULTS Compared with usual care, the incremental cost per QALY of ERS is £20 876. Based on a cohort of 100 000 individuals, CCA estimates cost of ERS at £22 million to the healthcare provider and £12 million to participants. The benefits of ERS include additional 3900 people becoming physically active, 51 cases of CHD avoided, 16 cases of stroke avoided, 86 cases of diabetes avoided and a gain of ∼800 QALYs. CONCLUSIONS CCA might provide greater transparency than CUA in reporting the outcomes of public health interventions and have greater resonance with stakeholders involved in commissioning these interventions.