Sci Med Footb. 2022 Sep 14. doi: 10.1080/24733938.2022.2125170. Online ahead of print.
ABSTRACT
Relative Age Effects (RAEs) appear largely throughout youth soccer. However, little is known about how RAEs at youth levels can impact selection and performance at senior levels. Accordingly, the purpose of this study was twofold: (a) to provide further test of RAEs by exploring the birth quarter (BQ) distribution of 2,030 Italian players born from 1975 to 2001 (both years included) who have played in any of the Youth National Italian Soccer Teams (U15-U21); and (b) to investigate how RAEs influence future career outcomes, by exploring the BQ distribution of players who completed the transition from youth levels to the Senior National Team (n=182) and those who eventually achieved the Super International Achievers (SIA) status (i.e., plating at a senior level in a UEFA European Championship and/or FIFA World Championship; n=58). Chi-square statistics revealed a significantly skewed (all P value <0.0001) BQ distributions for all Youth squads (BQ1=41.4% vs. BQ4=10.8%), and for the cohort of players who completed the transition (P=0.003). In contrast, results from the Odds Ratios (ORs) highlighted how BQ4s are more likely to transition from youth-to-senior compared to BQ1s (ORs from 2.81 to 4.31). Results showed relatively older players remain overrepresented at senior level likely due to a residual bias effect. Whereas relatively younger players who were able to overcome selection process at youth levels had the highest likelihood of competing at senior levels. Therefore, involving players career trajectories in RAEs studies is needed to understand how relative age impacts career outcomes of early selected players.
PMID:36103671 | DOI:10.1080/24733938.2022.2125170
