A contingent valuation study for use in valuing public goods with health externalities: the case of street pianos

Background: Clinical healthcare is not the only way to improve an individual’s health. Community-based interventions can have health and wellbeing impacts as well; however, the nature of these interventions, which have public good characteristics, poses challenges for the typical ways in which we value outcomes for use in (health) economic evaluations. The approaches to valuation of these type of interventions should allow for the incorporation of all types of values including option value, externalities and individual use-value. Objective: This is a feasibility study with the objective to re-consider the importance of health externalities when valuing public health interventions that are treated as public goods from an economic perspective. Methods: A contingent valuation (CV) survey was designed to elicit individual willingness to pay (WTP) for the public piano programme (PPP). Five different scenarios were designed; three scenarios focussed on individual use–value, while the other two (scenarios 4 and 5) covered option values and externalities. An online survey was conducted with a sample of 105 people. Results: Preferences differed across the different scenarios. The mean WTP for scenario 1 was £0.81, for scenario 2 £3.65, for scenario 3 £3.07, for scenario 4 £7.26 and for scenario 5 £6.02. The WTP results for each scenario are presented and discussed regarding the nature of the good, user and non-user perspectives, payment vehicles and individual characteristics. Conclusion: This study provides evidence that all types of use are necessary for inclusion in an economic evaluation, especially when the good in question is a public good where its benefits can be obtained from all community members.