ArticlePloS one2022
Variations in the relative age effect with age and sex, and over time-Elite-level data from international soccer world cups.
Article in PloS one, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed.
- Cross-national and historical variation in relative age effects in professional football.PloS one · 2026Article
- Relative age effect in high-skill labor markets: evidence from the NBA.Frontiers in sports and active living · 2026Article
- Soccer health, performance, and injury prevention in highly trained youth soccer players: a public health approach.Frontiers in public health · 2026Article
- Relative age effects and implications for sport performance in elite Chinese junior male basketball players.BMC pediatrics · 2025Article
- Relative age effect and its impact on athletic performance among Chinese elite youth male basketball players.Scientific reports · 2025Article
- Born to win? Investigating the relative age effects in the big five European women's football leagues.Frontiers in sports and active living · 2025Article
- Article
- Where age doesn't matter: no relative age effects in esports at the professional level.Frontiers in sports and active living · 2025Article
- Relative age effects in European soccer: their association with contextual factors, impact on youth national teams' performance, and presence at the senior level.Frontiers in sports and active living · 2025Article
- Relative age effect in the 2022-2023 World Fencing Championships.Frontiers in sports and active living · 2025Article
- Relative age effect across the talent identification process of youth female soccer players in the United States: Influence of birth year, position, biological maturation, and skill level.Biology of sport · 2024Article
- How to Compare Relative Age Effect in Different Sports? A New Methodological Approach-Example of Youth Olympic Games.Sports (Basel, Switzerland) · 2024Article
- Relative Age Effect Analysis in the History of the Ballon d'Or (1956-2023).Sports (Basel, Switzerland) · 2024Article
- Is There a Relative Age Effect among the Most Successful Track and Field Athletes?Journal of human kinetics · 2024Article
- The relative age effect and its influence on athletic performance in Chinese junior female' tennis players.PloS one · 2024Article
- Age and Maturation Matter in Youth Elite Soccer, but Depending on Competitive Level and Gender.International journal of environmental research and public health · 2023Article
- The relative age effect among Chinese junior men's tennis players and its impact on sports performance.PloS one · 2023Article
- Article
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Authors and funding
4 authors.
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No grant is acknowledged in the PubMed record.
Abstract
The relative age effect (RAE) is a statistical bias observed across sport contexts and consists of a systematic skewness in birth date distribution within an annual-age cohort. In soccer, January 1st is the common cut-off date when categorizing players in competitions according to their chronological age, which potentially disadvantages those within the cohort who were born later in the year. Thus, relatively older soccer players in their cohort can be favored in talent identification, selection, and development. The aim of the current study was to investigate the variations in RAE in male and female international youth world-cup tournaments (U17 and U20) in the period from 1997-2019 and in international senior world-cup-tournaments from 2006-2019. A total of 20,401 soccer players participating in 47 different tournaments were analyzed. The birthdate distributions were categorized into four quartiles (January-March, Q1; April-June, Q2; July-September, Q3; October-December, Q4) and compared to a uniform distribution using Chi-square analysis with Cramer's V (Vc) as a measure of effect size. Based on the existing data concerning RAE in elite junior and senior soccer, it was hypothesized that: (I) the RAE is present in youth soccer world cup tournaments but is stronger in male players than in female players; (II) the younger the soccer players, the stronger the RAE; and (III) the RAE in world cup soccer tournaments has strengthened over time. All these hypotheses were supported by the data; novel findings included that the effect has now entered women's soccer, and in men's soccer it persists into senior world cup tournaments. Thus, a strong RAE bias occurs in selection among elite soccer players competing in international world cup tournaments.
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