Evidence map›Paper›PMID 42328316›Full record

ReviewFrontiers in sports and active living2026

Relative age effects in Rugby union and Rugby league: a systematic review and meta-analysis.

P R Brustio, S Cobley, A N Ungureanu, A B T McAuley, C Lupo, G Boccia, K Till, A L Kelly

Abstract readReview
In one paragraph

Review in Frontiers in sports and active living, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–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

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

P R BrustioDepartment of Clinical and Biological Sciences, University of Turin, Turin, Italy.
S CobleyDiscipline of Exercise & Sport Science, Faculty of Health Sciences, The University of Sydney, Sydney, NSW, Australia.
A N UngureanuNeuromuscular Function Research Group, School of Exercise & Sport Sciences, University of Turin, Turin, Italy.
A B T McAuleyResearch for Athlete and Youth Sport Development (RAYSD) Lab, Centre for Life and Sport Sciences (CLaSS), Faculty of Health, Education and Life Sciences, Birmingham City University, Birmingham, United Kingdom.
C LupoNeuromuscular Function Research Group, School of Exercise & Sport Sciences, University of Turin, Turin, Italy.
G BocciaDepartment of Clinical and Biological Sciences, University of Turin, Turin, Italy.
K TillCarnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom.
A L KellyResearch for Athlete and Youth Sport Development (RAYSD) Lab, Centre for Life and Sport Sciences (CLaSS), Faculty of Health, Education and Life Sciences, Birmingham City University, Birmingham, United Kingdom.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Introduction: Relative Age Effects (RAEs) are prominent factors affecting youth sport participation and talent identification and selection processes. In rugby, RAEs appear to be prevalent in both Rugby League (RL) and Rugby Union (RU), yet no study has quantitatively synthesised the available evidence across codes. This systematic review and meta-analysis aimed to identify RAE prevalence, magnitude, and moderating factors (i.e., sex, age, and competition level) across rugby codes, using the extreme-quartile contrast between Q1 and Q4. Methods: A systematic search in CINAHL, Ovid, PsycINFO, PubMed, Scopus, and Web of Science identified 26 eligible studies. Distribution data were synthesised using odds ratio meta-analyses with an inverse-variance random-effects model and separate analyses by sex, age, and competition level. Results: Male players showed a significant overrepresentation in Q1 vs. Q4 (34.8% vs. 16.9%; OR = 1.99), with smaller but similar effects in female players (27.5% vs. 23.6%; OR = 1.15). In males, RAEs were stronger in youth than senior categories (OR = 2.42 vs. 1.41), and in younger (U7-U14; U15-U17) vs. older age groups (U18-U20). Discussion: Descriptively, RAEs appeared larger at higher competition levels, particularly in youth males (regional/Local: OR = 2.14; national: OR = 2.76). Overall, findings demonstrate that RAEs are pervasive in rugby and persist across sex, age, and competition level. However, the magnitude of the pooled estimates should be interpreted cautiously in light of the substantial between-study heterogeneity and the attenuation of the male effect following adjustment.

Indexed as

competition levelRAErelative ageselection biassex differencestalent identificationyouth sport

Identifiers

PMID42328316
PMCPMC13279214

What Socratic holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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 Socratic graph.