The Norwegian Sports Membership Database: Coverage, biases and potential

This study describes the Norwegian Sports Membership Database (NSMD), assesses its coverage, and develops definitions of active sports memberships.

We validated the coverage of the NSMD, a database capturing individual-level sports memberships among people aged 10-70 years between 2015 and 2024. We compared yearly membership counts in the NSMD with figures from official reports from the Norwegian Olympic and Paralympic Committee and Confederation of Sports (NIF). We defined all memberships as lasting one day or longer, and active memberships as lasting at least one season or with a paid licence.

Between 2015 and 2024, the NSMD contained 3,148,213 memberships, of which 2,180,621 (60%) were considered active. In total, there were 1,606,048 unique individuals across 55 sports federations and 279 disciplines. Football accounted for 24% of all memberships, handball for 11% and gymnastics for 9%. Database coverage was low in 2015, accounting for 11%-16% of expected memberships, but it improved substantially over time, exceeding 85% of all memberships and 92% of active memberships in 2023 for those aged 13-19.

The coverage of the NSMD is high in recent years, representing a level of completeness that allows meaningful population-level analyses from 2019, although with large variations between sports. Linking sports data with health and socio-demographic outcomes provides a potentially significant opportunity for population-based research on sports participation and health across the lifespan.