Diversity of Group Memberships Predicts Well-Being: Cross-Sectional and Longitudinal Evidence.

Groups have their health and well-being impacted by satisfying their members' needs and providing resources to help cope with threats. Multiple group memberships serve to accumulate these benefits and also provide resilience to the effects of group loss. However, the additional well-being benefits of belonging to multiple different types of group remain to be determined. In a preregistered cross-sectional survey in Nottingham, England (Study 1, N = 328), we found that group-type diversity predicted well-being and that this effect was fully serially mediated by increased creative self-efficacy, then reduced loneliness. To confirm our hypothesis in a more robust sample we conducted longitudinal analyses on the English Longitudinal Study of Aging (ELSA) dataset (Study 2, N = 5,838) finding that group-type diversity at time one (T1) predicted well-being at T2 (4 years later), even when accounting for wellbeing and loneliness at T1. We discuss the implications for enhancing group-based health interventions.