Estimating the heterogeneous health and well-being returns to social participation.

Social participation is defined as an individual's involvement in activities that provide connections with others in society. Past research has demonstrated links between social participation, improved health and well-being, and reduced social isolation, but has been restricted to older people and has not investigated heterogeneity. Using cross-sectional data from the UK's Community Life Survey (2013-2019; N = 50,006), we estimated returns to social participation in the adult population. We included availability of community assets as instruments in a marginal treatment effects model, which allows treatment effects to be heterogeneous and examines whether the effects vary by propensity to participate. Social participation was linked to reduced loneliness and improved health (-0.96 and 0.40 points respectively on 1-5 scales) and increased life satisfaction and happiness (2.17 and 2.03 points respectively on 0-10 scales). These effects were larger for those on low income, with lower education attainment, and who live alone or with no children. We also found negative selection, indicating those less likely to participate have higher health and well-being returns. Future interventions could focus on increasing community asset infrastructure and encouraging social participation for those with lower socio-economic status.