Faculty of Human Kinetics, University of Windsor, Windsor, ON, Canada.
Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK.
Sports Med. 2018 Jun;48(6):1451-1478. doi: 10.1007/s40279-018-0890-8.
Subtle 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.
The 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.
Registered 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.
When 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.
The 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.
在体育（双）年龄分组中，年龄的细微差异可能会导致即时参与和长期成就的差异，这被称为相对年龄效应。大量研究已经检查了男性体育中的相对年龄效应；然而，女性体育中相对年龄效应的普遍性和特定背景下的程度仍未确定。
本研究的目的是通过检查 1984 年至 2016 年期间发表的数据，确定女性体育中相对年龄效应的普遍性和程度。
使用 PROSPERO（编号 42016053497）进行注册，并遵循系统评价和荟萃分析的首选报告项目的系统搜索指南，确定了 57 项研究，其中包含 25 项运动中的 308 个独立样本。使用比值比荟萃分析合成分布数据，应用不变随机效应模型。后续亚组类别分析检查了相对年龄效应程度是否受年龄组、比赛水平、运动类型、运动环境和研究质量的调节。
当比较所有女性运动环境中相对最年长（第 1 四分位数）和最年轻（第 4 四分位数）的个体时，整体汇总估计确定了一个显著但较小的相对年龄效应（比值比=1.25；95%置信区间 1.21-1.30；p=0.01；调整后的比值比=1.21）。亚组分析显示，在青少年前期（≤11 岁）和青少年期（12-14 岁）年龄组以及较高的比赛水平下，相对年龄效应程度更高。在团队和个人运动环境中，相对年龄效应程度更高，这些环境与高生理需求相关。
研究结果强调了相对年龄效应在研究中检查的女性运动环境中普遍存在。相对年龄效应程度受发展阶段、比赛水平和运动环境需求之间相互作用的调节。建议修改体育政策、组织和运动员发展系统结构以及从业人员干预措施，以防止与相对年龄效应相关的参与和长期成就不平等。
