What Makes a Champion? Early Multidisciplinary Practice, Not Early Specialization, Predicts World-Class Performance - Güllich, A; Macnamara, BN; Hambrick, DZ (2022)
meta-analysis; evidence grade C

Annual Age-Grouping and Athlete Development: A Meta-Analytical Review of Relative Age Effects in Sport - Cobley, S; Baker, J; Wattie, N; McKenna, J (2009)
meta-analysis; evidence grade C

Relative age effect reversal on the junior-to-senior transition in world-class athletics - Brustio, PR; Stival, M; Boccia, G (2023)
longitudinal; evidence grade C

Sport Specialization and Risk of Overuse Injuries: A Systematic Review With Meta-analysis - Bell, DR; Post, EG; Biese, K; Bay, C; Valovich McLeod, T (2018)
meta-analysis; evidence grade C

A Prospective Study on the Effect of Sport Specialization on Lower Extremity Injury Rates in High School Athletes - McGuine, TA; Post, EG; Hetzel, SJ; Brooks, MA; Trigsted, S; Bell, DR (2017)
longitudinal; evidence grade C

Risk of Injuries Associated With Sport Specialization and Intense Training Patterns in Young Athletes: A Longitudinal Clinical Case-Control Study - Jayanthi, N; Kleithermes, S; Dugas, L; Pasulka, J; Iqbal, S; LaBella, C (2020)
quasi-experiment; evidence grade C

Comparing Burnout in Sport-Specializing Versus Sport-Sampling Adolescent Athletes: A Systematic Review and Meta-analysis - Giusti, NE; Carder, SL; Vopat, L; Baker, J; Tarakemeh, A; Vopat, B; Mulcahey, MK (2020)
meta-analysis; evidence grade D