Evidence map›Paper›PMID 29536262›Full record

SynthesisSports medicine (Auckland, N.Z.)2018

Relative Age Effects Across and Within Female Sport Contexts: A Systematic Review and Meta-Analysis.

Kristy L Smith, Patricia L Weir, Kevin Till, Michael Romann, Stephen Cobley

Erratum issuedAbstract readMeta-AnalysisSystematic Review
PubMed Publisher
In one paragraph

Synthesis in Sports medicine (Auckland, N.Z.), 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 107 papers, 7 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
107citing papers in PubMed, 7 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

107 citing papers in PubMed, 7 syntheses or guidelines pooled it.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Prevalence and Impact of the Relative Age Effect on Competition Performance in Swimming: A Systematic Review.International journal of environmental research and public health · 2021
    Pooled it
  5. Impact of the Relative Age Effect on Competition Performance in Basketball: A Qualitative Systematic Review.International journal of environmental research and public health · 2020
    Pooled it
  6. Pooled it
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  8. Article
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  12. Review
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  15. Article
  16. Positional relative age effect in europe's top ten football leagues.BMC sports science, medicine & rehabilitation · 2025
    Article
  17. Article
  18. Article
  19. Relative Age Effect Among World-Class Jump Athletes.Journal of sports science & medicine · 2025
    Article
  20. Review

47 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

5 authors.

Kristy L SmithFaculty of Human Kinetics, University of Windsor, Windsor, ON, Canada.
Patricia L WeirFaculty of Human Kinetics, University of Windsor, Windsor, ON, Canada.
Kevin TillInstitute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK.
Michael RomannSwiss Federal Institute of Sport Magglingen, Magglingen, Switzerland.
Stephen CobleyExercise and Sport Sciences, Faculty of Health Sciences, The University of Sydney, Cumberland Campus, 75 East St, Lidcombe, Sydney, NSW, 2141, Australia. stephen.cobley@sydney.edu.au.ORCID 0000-0002-9679-3513

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSubtle differences in chronological age within sport (bi-) annual-age groupings can contribute to immediate participation and long-term attainment discrepancies; known as the relative age effect. Voluminous studies have examined relative age effects in male sport; however, their prevalence and context-specific magnitude in female sport remain undetermined.

objectiveThe objective of this study was to determine the prevalence and magnitude of relative age effects in female sport via examination of published data spanning 1984-2016.

methodsRegistered with PROSPERO (No. 42016053497) and using Preferred Reporting Items for Systematic Reviews and Meta-analysis systematic search guidelines, 57 studies were identified, containing 308 independent samples across 25 sports. Distribution data were synthesised using odds ratio meta-analyses, applying an invariance random-effects model. Follow-up subgroup category analyses examined whether relative age effect magnitudes were moderated by age group, competition level, sport type, sport context and study quality.

resultsWhen comparing the relatively oldest (quartile 1) vs. youngest (quartile 4) individuals across all female sport contexts, the overall pooled estimate identified a significant but small relative age effect (odds ratio = 1.25; 95% confidence interval 1.21-1.30; p = 0.01; odds ratio adjusted = 1.21). Subgroup analyses revealed the relative age effect magnitude was higher in pre-adolescent (≤ 11 years) and adolescent (12-14 years) age groups and at higher competition levels. Relative age effect magnitudes were higher in team-based and individual sport contexts associated with high physiological demands.

conclusionThe findings highlight relative age effects are prevalent across the female sport contexts examined. Relative age effect magnitude is moderated by interactions between developmental stages, competition level and sport context demands. Modifications to sport policy, organisational and athlete development system structure, as well as practitioner intervention are recommended to prevent relative age effect-related participation and longer term attainment inequalities.

Indexed as

Age FactorsExerciseSportsAdolescentAdultAge DistributionAustraliaFemaleHumansMalePhysical Education and Training

Identifiers

PMID29536262

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.