858 FO44 – Development and validation of a sport specialization index focused on physical, motivational and social characteristics of youth sport participation

Background No validated measurement tool currently exists to assess a youth athlete's level of sport specialization; frequently used measures largely focus on physical characterizations of sport participation (e.g. number of sports, training volume) while neglecting athletes' motivations for and social effects of sport participation. There is a need for a validated tool that considers all aspects of sport specialization to better understand the relationship between specialization and risk of injury, illness and psychosocial consequences. Objective To develop and assess the psychometric properties of an index that measures a youth athlete's level of sport specialization and to further evaluate the index on a nationally representative dataset. Design and Setting Using a previously developed pool of sport specialization items with established content validity, a regional and national survey of items was administered to adolescent (14–18 years) athletes participating in any level of youth sport. Confirmatory factor analyses and Rasch partial credit modeling were used to develop and assess a sport specialization index using the regional survey data. The replicability of the index was evaluated with the national dataset. Participants 499 (66% Female, 13% non-white) and 517 (43% female, 44% non-white) athletes completed the regional and national surveys, respectively. Main Outcome Measurements The latent construct of sport specialization Results Fourteen of 25 tested items were retained in three dimensions (n=6 social, n=5 motivation, n=3 physical items) with all factor loadings statistically significant in both datasets. The three subdomains had acceptable internal consistency reliability (0.71–0.91) in the national dataset with slightly lower values in the regional (0.62–0.85). Infit and outfit mean square estimates suggested appropriate fit of all items (range: 0.74–1.25 and 0.65–1.74) in the regional and national datasets, respectively. Conclusions The youth sport specialization index assessing an athlete's beliefs, values, and consequences of sport participation demonstrated good psychometric performance.