Does Month of Birth Affect Speed and Quality of Transition from School to Work?

To determine whether youth in Alberta who had completed suicide were more likely to be younger than their classmates on entering grade 1 (that is, showed a relative age effect). Records were obtained for all deaths by suicide by individuals under the age of 20 years in Alberta during the years 1979-1992. The relative age of each of these persons was determined by comparing his or her month of birth to the birth months of the appropriate school-grade cohort. A disproportionate number of the subjects were born in the second half of the "school eligibility year," indicating a higher probability that those who completed suicide were younger than their classmates. Previous research indicates that relative age is strongly related to school performance and success in sports. The present study demonstrates that the relative age effect is also a factor in youth suicide. It is suggested that the higher incidence of youth suicide in the group of relatively younger school children may have resulted from poorer school performance, which in turn led to lowered confidence and self esteem. Past research suggests that these conditions may predispose children to hopelessness and depression, which are often thought to be essential components of suicide. Research aimed at neutralizing the negative effects of relative age should have important personal and social consequences.

This aim of this study is to examine the Relative Age Effect (RAE) in weightlifting by analysing the distribution of athletes' birth months. Data on birth dates and performance were collected for 3519 male and female athletes competing in the U15, Youth, Junior, and U23 categories at the European Weightlifting Championships between 2018 and 2023 (excluding 2020), sourced from the European Weightlifting Federation’s official records. Observed and expected distributions according to birth month were compared using the Pearson chi-square (χ²) test, while one-way ANOVA and Welch ANOVA were employed to assess the effects of birth month on total weight lifted and medal acquisition. The results revealed significant deviations from an even distribution, with a marked overrepresentation of athletes born in the first quarter of the year, indicating the presence of RAE. This pattern was particularly pronounced in the U15 and Junior categories. Analyses further demonstrated that birth month had a significant effect on total weight lifted in specific age and weight categories; however, no significant effect was found between birth month and medal attainment. These findings may indicate that weightlifters born in the earlier months of the year gain certain advantages in terms of representation and performance compared to their peers, primarily due to early developmental benefits. However, this situation does not singularly determine athletic success; rather, it can unjustly narrow the talent pool and potentially hinder long-term development. Furthermore, factors such as training duration, cumulative experience, and individual developmental trajectories also play a decisive role in shaping performance outcomes. Overall, the study highlights the need to consider the impact of relative age when developing talent identification and athlete development programmes within weightlifting.

Aims: This study investigated the existence of Relative Age Effect (RAE) in the selection process of male and female athletes in the Brazilian national handball teams according to age categories (U-18, U-21, and senior) and playing position (wings, backs, pivots, and goalkeepers). Methods: In order to determine RAE, athletes were divided based on their months of birth; quarters Q1 (January-March), Q2 (April-June), Q3 (July-September), and Q4 (October-December). Data were collected from the official Brazilian Handball Confederation (CBHb) website and included the athletes that participated in training and/or competitions composing the Brazilian national teams from 2014 to 2018. To determine the RAE on playing positions, age categories of male and female groups were pooled. Chi-squared tests were performed to investigate the RAE. Results: An over-representation of players born in Q1 and Q2 in the U-18, U-20, and senior categories of male teams and the U-20, and senior female teams were found. In the male teams, as the age category increased, RAE decreased, but still existed. Such distribution was reversed in the female athletes, with a higher RAE magnitude in the senior category as compared to U-18 and U-21. Additionally, it seems that RAE is dependent on the playing position only for male athletes (wings and backs) whereas RAE was found for all playing positions in female athletes. Conclusion: Overall, RAE was found in Brazilian national handball teams, but its magnitude and form of manifestation seem to be influenced by sex, category, and playing position.

The main purpose of this study is to identify the relative effect of age (RAE) according to norm values on the anthropometric performance and physical fitness of children between the ages of 9 and 11 years. The data, namely the percentiles of anthropometric parameters and physical fitness, are relevant for identifying the RAE in relation to gender and the month of birth in children. For the sample in this study, 1185 young people from Kosovo were enrolled, including 626 males and 559 females aged 9-11 years. The gathered data were assessed via the EUROFIT methodology, which takes into account comparisons based on the quartile of birth and the relative age effect (RAE). The results of the data show us that there are significant differences in the RAE among children born in Q2 at the age of 9 years, especially in boys, as well as significant differences in the height variable at the <0.005 significance level. Others factors did not show significant differences, for example, variables that are indicators of physical fitness. For both boys and girls born in Q1, significant differences were mainly found in the indicators of explosive strength, flexibility, static strength, speed, and agility, with a level of significance of p < 0.001, while other indicators did not show significant differences. In addition, there was a significant difference the ratio between genders at the p < 0.001 and p < 0.005 levels, mainly among those born in Q1 and Q2. Similarly, at 10 years of age, children who were born earlier in the year had better scores, although the large disparities were more noticeable between quartiles than between genders, where the significant differences were mainly in the indicators of explosive strength, speed, and strength at the p < 0.001 level, as well as static strength, agility, and speed at the p < 0.005 level. Significant differences were also found for the indicators in terms of gender. At the age of 11, significant percentiles were mainly found in the quartiles at the beginning of the year for both boys and girls, and significant differences were also found at the p < 0.001 level for RAE between quartiles and gender. By using these data, it will be possible to highlight how males, who have demonstrated notable advantages in anthropometric and physical fitness measures, as well as those born in the first few months of the year, exhibit a relative age effect (RAE) in accordance with gender norm values.

To verify whether relative age effects (RAEs) occur among young male and female Swiss Alpine skiers of different age groups and performance levels. In addition, the efficacy of normalizing performance in physical tests to height and body mass to attenuate RAEs eventually present was tested. The Swiss Ski Power Test consists of anthropometric measures and physical tests for coordination and speed, endurance, and strength and has been used since 2004 to evaluate 11- to 19-y-old Swiss competitive Alpine skiers. The authors analyzed the distribution of 6996 tests performed by 1438 male and 1031 female Alpine skiers between 2004 and 2011 according to the athletes' respective relative age quartiles. Differences in anthropometric measures and performance in physical tests according to quartile were assessed, and the possibility of attenuating eventual RAEs on performance by normalization of results to height and body mass was tested. RAEs were found among all female and male age groups, with no differences between age groups. While performance level did not affect RAE for male skiers, it influenced RAE among female skiers. RAEs also influenced results in all physical tests except upper-limb strength. Normalization of results to body mass attenuated most RAEs identified. Small RAEs are present among young Swiss competitive Alpine skiers and should be taken into account in training and selection settings to prevent the waste of possible future talents. When ranking junior athletes according to their performance in physical tests, normalization of results to body mass decreases the bias caused by RAEs.

Relative Age Effects (RAEs) refer to the selection and performance differentials between children and youth who are categorized in annual-age groups. In the context of Swiss 60m athletic sprinting, 7761 male athletes aged 8 – 15 years were analysed, with this study examining whether: (i) RAE prevalence changed across annual age groups and according to performance level (i.e., all athletes, Top 50%, 25% & 10%); (ii) whether the relationship between relative age and performance could be quantified, and corrective adjustments applied to test if RAEs could be removed. Part one identified that when all athletes were included, typical RAEs were evident, with smaller comparative effect sizes, and progressively reduced with older age groups. However, RAE effect sizes increased linearly according to performance level (i.e., all athletes – Top 10%) regardless of age group. In part two, all athletes born in each quartile, and within each annual age group, were entered into linear regression analyses. Results identified that an almost one year relative age difference resulted in mean expected performance differences of 10.1% at age 8, 8.4% at 9, 6.8% at 10, 6.4% at 11, 6.0% at 12, 6.3% at 13, 6.7% at 14, and 5.3% at 15. Correction adjustments were then calculated according to day, month, quarter, and year, and used to demonstrate that RAEs can be effectively removed from all performance levels, and from Swiss junior sprinting more broadly. Such procedures could hold significant implications for sport participation as well as for performance assessment, evaluation, and selection during athlete development.

This article analyzes the relative age effect (RAE) in German elite youth soccer. We hypothesize that, to get selected by elite youth academies, players with relative age disadvantages must be relatively more talented; especially at the margin of getting selected. Using data on 2,383 former elite youth players and their later market values, we show that the RAE was substantial in German elite youth soccer between 2000 and 2020. Moreover, in the sample of former elite youth academy players, those with relative age disadvantages reach significantly higher market values. Our results indicate that relative age disadvantages of elite academy players are positively correlated with their unobserved ability; suggesting that, on average, the RAE results in a loss of talent—and market value. We find that clubs could generate 30.6 to 72.8% higher market values without the RAE.

Relative age effects (RAEs), where older children within an age-based group have better academic, sporting, self-concept and mental health outcomes than their younger peers, have been demonstrated in multiple countries. Australian research has found self-concept and Attention Deficit Hyperactivity Disorder RAEs, but academic RAEs have not been explored. This cross-sectional observational study investigated RAEs among Western Australian year 3, 5, 7 and 9 government school students who took a National Assessment Program - Literacy and Numeracy (NAPLAN) test in Numeracy, Reading, Spelling, or Grammar and Punctuation in 2017. After adjusting for gender and Aboriginal and Torres Strait Islander status, we found that among the 98% of students who were in their recommended school year, younger students were on average significantly outperformed by their older classmates in all tests. RAEs were strongest in year 3, and progressively weakened through years 5, 7 and 9. These results are consistent with international research. They also support the hypothesis that age-related immaturity of relatively young children disadvantages them in academic competition, but this decreases as the age difference becomes a smaller proportion of their lived years. We also examined the performance of the 2% of children who were outside their recommended year. Accelerated students on average significantly outperformed their older classmates. Delayed progress students performed significantly worse than their younger classmates. A likely explanation for this reverse RAE is that accelerated students are often promoted because they are high academic achievers and delayed children are held back because they are performing below expectations.

The aims of this study were 1) to analyze the influence of chronological age, relative age, and biological maturation on accumulated training load and perceived exertion in young sub-elite football players and 2) to understand the interaction effects amongst age grouping, maturation status, and birth quartiles on accumulated training load and perceived exertion in this target population. A 6-week period (18 training sessions and 324 observation cases) concerning 60 young male sub-elite football players grouped into relative age (Q1 to Q4), age group (U15, U17, and U19), and maturation status (Pre-peak height velocity (PHV), Mid-PHV, and Post-PHV) was established. External training load data were collected using 18 Hz global positioning system technology (GPS), heart-rate measures by a 1 Hz short-range telemetry system, and perceived exertion with total quality recovery (TQR) and rating of perceived exertion (RPE). U17 players and U15 players were 2.35 (95% CI: 1.25–4.51) and 1.60 (95% CI: 0.19–4.33) times more likely to pertain to Q1 and Q3, respectively. A negative magnitude for odds ratio was found in all four quartile comparisons within maturation status (95% CI: 6.72–0.64), except for Mid-PHV on Q2 (95% CI: 0.19–4.33). Between- and within-subject analysis reported significant differences in all variables on age group comparison measures (F = 0.439 to 26.636, p = 0.000 to 0.019, η2 = 0.003–0.037), except for dynamic stress load (DSL). Between-subject analysis on maturity status comparison demonstrated significant differences for all training load measures (F = 6.593 to 14.424, p = 0.000 to 0.037, η2 = 0.020–0.092). Interaction effects were found for age group x maturity band x relative age (Λ Pillai’s = 0.391, Λ Wilk’s = 0.609, F = 11.385, p = 0.000, η2 = 0.391) and maturity band x relative age (Λ Pillai’s = 0.252, Λ Wilk’s = 0.769, F = 0.955, p = 0.004, η2 = 0.112). Current research has confirmed the effects of chronological age, relative age, and biological maturation on accumulated training load. Perceived exertion does not seem to show any differences concerning age group or maturity status. Evidence should be helpful for professionals to optimize the training process and young football players’ performance.

Despite their prevalence, the longitudinal impacts of relative age effects (RAEs) on sport and other forms of physical activity (PA) are understudied. This study examined longitudinal participation patterns in organized sport (team and individual), unorganized PA, and non-participation with respect to RAEs in a prospective cohort of adolescents. Data from the first 24 cycles of the MATCH study were used for analyses. Elementary students (n = 929) were recruited from 17 schools in Atlantic Canada. Respondents self-reported PA three times/year. Mixed multilevel logistic models compared the likelihood of participating in each context across birth quarter. Chronological age and gender were considered, along with the interaction between chronological and relative age. Individuals born in Quarter 1/Quarter 2 were more likely to report participation in organized team sport but not individual sports. Relatively older participants born in Quarter 2 were more likely to report participation in unorganized PA. Increasing chronological age was associated with decreased participation in organized sport (particularly team-based) and increased non-participation. Gender was not associated with organized sport participation, but girls were under-represented in unorganized PA and more likely to report non-participation. The interaction parameters suggested that RAEs were consistent throughout adolescence in each context. Longitudinal analyses suggest RAEs are context dependent.

Background: Annual age grouping is a widely used strategy to allocate players to age categories for more equal and fair opportunities considering the developmental differences. Although it is a well-intended strategy, certain (dis)advantages occur because of the subtle age-related differences within the same age groups. Objective: The purpose of the current study was to investigate the relative age effect among badminton players reaching the podium in the last three consecutive European U15, U17 and Junior (U19) Badminton Championships. Methods: A total of 288 medal owners from 20 countries were evaluated in the study. Chi-square (χ2) goodness-of-fit tests were used to compare the obtained birth month distributions across the quartiles (Q), and odds ratios and 95% confidence intervals were calculated in order to compare quartiles with each other. Results: Statistically significant relative age effects were determined favouring relatively older athletes in the total sample (χ2 = 82.278, p < .001). Statistically significant distribution differences were noted in both singles and doubles categories in total (χ2 = 18.778, p < .001; χ2 = 63.815, p < .001, respectively). Striking findings were determined in Q1-Q4 and Q2-Q4 comparisons as players in Q1 and Q2 were more than five and four times as likely to reach the podium than players in Q4, respectively. Conclusions: Results of this study confirm the presence of relative age effect among award-winning badminton players which goes beyond the classical participation trends findings, and stress the importance of the issue for talent development, selection and success.

Relative age effects (when birthdate influences participation or performance) in sport potentially influence the experiences of sport participants, including athletes, parents, and coaches. Nearly all existing literature on relative age effects adopts a quantitative approach, limiting our understanding of the phenomenon. Thus, the purpose of this unique study was to explore relative age effects using an instrumental, descriptive case study approach with one elite, youth, male ice hockey team. This context was chosen given the high prevalence of relative age effects among such groups. Participants included 20 athletes, 19 parents, and two coaches from one team. Data were collected through biometric measures, semistructured interviews, and participant observations. Results were presented as five composite narratives: relatively older athletes, relatively younger athletes, parents of relatively older athletes, parents of relatively younger athletes, and coaching staff. The narratives demonstrated unique relative age experiences for each group of participants. Discussion aligns the results with the social agents model that explains relative age effects. Practical recommendations for sport participants are also provided.

The aims of this study were to test for the presence of a relative age effect among male (n = 119,715) and female (n = 12,823) members of the shooting sports federation, and to determine whether any such effect has an impact on dropout from the sport. For the boys and girls, the results show a uniform distribution of dropout. A relative age effect was not found for the girls, showing that in female shooting sports there is no such effect. For the males, a significant statistical relative age effect was not detected in the 18–20 and 13–14 year categories. However, a relative age effect was found among adults and the 11–12 and under 11 year categories. A significant “inverse” relative age effect was found for the 15–17 year group. Further qualitative research is needed to clarify which factors contribute to this asymmetric distribution of birth dates in French male shooting sports.

Relative age effects (RAEs) are a well-known phenomenon within youth sports. Although research consistently shows participation biases across the youth sporting domain, there appears to be a paucity of research focusing on interventions aimed at mitigating RAEs. This chapter aims to address this challenge by proposing a new grouping strategy to reduce RAEs. First, in contrast to the traditional approach using chi-squared goodness-of-fit test to determine RAEs, the average team age (ATA) and relative age effect index (RAEi) are introduced. These measurable variables are used to study the underlying mechanisms causing the relative age bias in youth football in the Netherlands. Results show that teams with an average age closer to the beginning of the cut-off date are more likely to win (e.g., 1.51 points per game for older teams vs. 1.32 points per game for younger teams). As such, a competitive advantage appears to increase the average age of teams within the selection year (e.g., a predetermined age group that is eligible to in a certain competition), creating an over-representation of relatively older players. Therefore, an alternative grouping strategy is proposed, whereby eligibility is based on the average age of a team rather than the individual age of the athlete competing inside the selection year. This ATA grouping approach operates by setting the average age of the team to create opportunities for both younger and older players to be selected and, potentially, for the reduction of RAEs. Since this grouping policy is yet to be empirically evaluated in practice, this chapter concludes with recommendations for future research to examine the ATA approach.

BackgroundOwing to the separation into age groups at the first winter Youth Olympic Games (YOG), athletes differed in age by up to two years, leading to a potential relative age...