Developmental contexts, depth of competition and relative age effects in sport: A database analysis and a quasi- experiment

Improving learning environments requires an understanding of biases and restrictions of current environments. The widely used policy of grouping youth into ‘age groups’ for education and sport promotes a persistent and pervasive developmental disadvantage known as the ‘relative age effect’. This investigation documents two studies examining the potential role of depth of competition in promoting relative age effects in sport. In Study 1, we considered effects across 49 European countries (N = 189,411) and their relationship with depth of competition. There were significant effects in 38 countries but they did not seem to be related to depth of competition as measured by UEFA club ranking, league, ratio of national to international players or inhabitants per country. Study 2 used a quasi-experimental approach to consider a linear relationship between the number of participants in a sport, the number of spots on a sports team and the size of relative age effects. Results did not support a linear relationship between these variables but provided some evidence of nonlinear interactions. Collectively, these results indicate that the relationships between competition variables and the size of relative age effects are more complex than previously hypothesized.