Transient Relative Age Effects across annual age groups in National level Australian Swimming

2018 ◽  
Vol 21 (8) ◽  
pp. 839-845 ◽  
Author(s):  
Stephen Cobley ◽  
Shaun Abbott ◽  
Sera Dogramaci ◽  
Adam Kable ◽  
James Salter ◽  
...  
2012 ◽  
Vol 24 (1) ◽  
pp. 72-83 ◽  
Author(s):  
Simon J. Roberts ◽  
Lynne M. Boddy ◽  
Stuart J. Fairclough ◽  
Gareth Stratton

The aims of this study were firstly to examine whether there was an observed relative age effect in the cardiorespiratory fitness scores of 9-10 and 11-12 year old children, and secondly whether any observed effect was maintained after controlling for somatic maturity. Cardiorespiratory fitness data from 11,404 children aged 9-10 years and 3,911 children aged 11-12 years were obtained from a large cross-sectional field-based fitness testing program. A one-way ANOVA revealed a statistically significant relative age effect (p < .01) existed in the 20mSRT scores across all the age groups. Furthermore, ANCOVA analyses identified a statistically significant relative age effect was maintained after controlling for somatic maturation (p < .05). From a public health perspective these results confirm the existence of relative age effects for the first time and consequently may hold implications for relatively younger children in the accurate assessment of their cardiorespiratory fitness scores.


2019 ◽  
Vol 14 (6) ◽  
pp. 714-725 ◽  
Author(s):  
Rickesh Patel ◽  
Alan Nevill ◽  
Ross Cloak ◽  
Tina Smith ◽  
Matthew Wyon

A professional English football club with Category 1 academy status was investigated to determine the magnitude of relative age effects (RAE) within the club and explore between-quartile differences for somatic maturity, anthropometry and physical performances. Birth dates of 426 players from Under 9 to First Team were categorised into four birth quartiles (Q) and examined for relative age effects. Additionally, data on 382 players (Under 11 to First Team) were obtained for somatic maturity, anthropometry, countermovement jump, sprint (10 and 30 m), agility T-test and Yo-Yo Intermittent Recovery Level 1 or 2 performance to determine between-quartile differences. Odds ratios revealed Q1 players were 6.0 times more likely to be represented than Q4 players. Multilevel modelling demonstrated between birth quartile similarities for each variable across all age groups, though there was a tendency for Q4 players to outperform Q1 players between Under 11 and Under 18 groups. Strong relative age effects exist within this club as well as a tendency to select players demonstrating advanced growth and/or maturity, with some indication that higher categorised academies in England may be at risk of amplified selection biases. Talent identification strategies in elite youth football should actively seek to adopt novel approaches to reduce selection biases and avoid wasted potential.


Author(s):  
Zsófia Tróznai ◽  
Katinka Utczás ◽  
Júlia Pápai ◽  
Zalán Négele ◽  
István Juhász ◽  
...  

Talent selection is often affected by the relative age effects (RAEs), resulting in the overrepresentation of relatively older (vs. relatively younger) players among those selected. The use of sport-specific tasks is suggested to reduce RAEs during talent selection. Purpose: To test the hypothesis that talent selection including only sport-specific tasks is not affected by the RAEs and to analyse the body size and biological maturity of the top selection level according to relative age. Methods: Participants were U14 female (n = 5428) and U15 (n = 4408) male handball players participating in four programs consisting of four selection levels (local, county, regional, and national) grouped in bi-annual age. Handball-specific generic skills, position-specific technical drills and in-game performance were the selection criteria evaluated by experts and coaches. Body dimensions were measured and bone age, as an indicator of maturity, was estimated. The relative age quartile distributions within the bi-annual cohorts were examined using Chi-square and Odds Ratios. Results: In terms of all the registered players no RAEs were evident. However, the RAEs of moderate effect size were evident at the county level; χ2 = 53.2 (girls) and 66.4 (boys), OR = 2.5 and 3.3, respectively. The RAEs of a large effect size were found at the regional level; χ2 = 139.5 (girls) and 144.9 (boys), OR = 8.2 and 5.2, respectively. At national level, RAEs were still present, but with no further increase in the effect size. At the highest selection level, there were no differences in the anthropometric measures between the relatively older and younger players. Conclusion: The findings provide support to the hypothesis that the selection process exacerbates RAEs even when using only sport-specific selection criteria. The performance metrics in technical skills, but also coaching assessments are likely involved. In addition, an advanced maturity and/or an above-average body size increases the selection odds for relatively younger players.


Sports ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 99
Author(s):  
Michael Romann ◽  
Marie Javet ◽  
Stephen Cobley ◽  
Dennis-Peter Born

Background: In football, annual age-group categorization leads to relative age effects (RAEs) in talent development. Given such trends, relative age may also associate with market values. This study analyzed the relationship between RAEs and market values of youth players. Methods: Age category, birthdate, and market values of 11,738 youth male football players were obtained from the “transfermarkt.de” database, which delivers a good proxy for real market values. RAEs were calculated using odds ratios (OR) with 95% confidence intervals (95%CI). Results: Significant RAEs were found across all age-groups (p < 0.05). The largest RAEs occurred in U18 players (Q1 [relatively older] v Q4 [relatively younger] OR = 3.1) ORs decreased with age category, i.e., U19 (2.7), U20 (2.6), U21 (2.4), U22 (2.2), and U23 (1.8). At U19s, Q1 players were associated with significantly higher market values than Q4 players. However, by U21, U22, and U23 RAEs were inversed, with correspondingly higher market values for Q4 players apparent. While large typical RAEs for all playing positions was observed in younger age categories (U18–U20), inversed RAEs were only evident for defenders (small-medium) and for strikers (medium-large) in U21–U23 (not goalkeepers and midfielders). Conclusions: Assuming an equal distribution of football talent exists across annual cohorts, results indicate the selection and market value of young professional players is dynamic. Findings suggest a potential biased selection, and undervaluing of Q4 players in younger age groups, as their representation and market value increased over time. By contrast, the changing representations and market values of Q1 players suggest initial overvaluing in performance and monetary terms. Therefore, this inefficient talent selection and the accompanying waste of money should be improved.


Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 407
Author(s):  
Ana Luiza Bierrenbach ◽  
Yoonyoung Choi ◽  
Paula de Mendonça Batista ◽  
Fernando Brandão Serra ◽  
Cintia Irene Parellada ◽  
...  

Background: In 2014, a recommended one-dose of inactivated hepatitis A vaccine was included in the Brazilian National Immunization Program targeting children 12–24 months. This decision addressed the low to intermediate endemicity status of hepatitis A across Brazil and the high rate of infection in children and adolescents between 5 and 19 years old. The aim of the study was to conduct a time-series analysis on hepatitis A incidence across age groups and to assess the hepatitis A distribution throughout Brazilian geographic regions. Methods: An interrupted time-series analysis was performed to assess hepatitis A incidence rates before (2010–2013) and after (2015–2018) hepatitis A vaccine program implementation. The time-series analysis was stratified by age groups while a secondary analysis examined geographic distribution of hepatitis A cases. Results: Overall incidence of hepatitis A decreased from 3.19/100.000 in the pre-vaccine period to 0.87/100.000 (p = 0.022) post-vaccine introduction. Incidence rate reduction was higher among children aged 1-4 years old, with an annual reduction of 67.6% in the post-vaccination period against a 7.7% annual reduction in the pre-vaccination period (p < 0.001). Between 2015 and 2018, the vaccination program prevented 14,468 hepatitis A cases. Conclusion: Our study highlighted the positive impact of a recommended one-dose inactivated hepatitis A vaccine for 1–4-years-old in controlling hepatitis A at national level.


Author(s):  
Michal Kafri ◽  
Patrice L. Weiss ◽  
Gabriel Zeilig ◽  
Moshe Bondi ◽  
Ilanit Baum-Cohen ◽  
...  

Abstract Background Virtual reality (VR) enables objective and accurate measurement of behavior in ecologically valid and safe environments, while controlling the delivery of stimuli and maintaining standardized measurement protocols. Despite this potential, studies that compare virtual and real-world performance of complex daily activities are scarce. This study aimed to compare cognitive strategies and gait characteristics of young and older healthy adults as they engaged in a complex task while navigating in a real shopping mall and a high-fidelity virtual replica of the mall. Methods Seventeen older adults (mean (SD) age = 71.2 (5.6) years, 64% males) and 17 young adults (26.7 (3.7) years, 35% males) participated. In two separate sessions they performed the Multiple Errands Test (MET) in a real-world mall or the Virtual MET (VMET) in the virtual environment. The real-world environment was a small shopping area and the virtual environment was created within the CAREN™ (Computer Assisted Rehabilitation Environment) Integrated Reality System. The performance of the task was assessed using motor and physiological measures (gait parameters and heart rate), MET or VMET time and score, and navigation efficiency (cognitive performance and strategy). Between (age groups) and within (environment) differences were analyzed with ANOVA repeated measures. Results There were no significant age effects for any of the gait parameters but there were significant environment effects such that both age groups walked faster (F(1,32) = 154.96, p < 0.0001) with higher step lengths (F(1,32) = 86.36, p < 0.0001), had lower spatial and temporal gait variability (F(1,32) = 95.71–36.06, p < 0.0001) and lower heart rate (F(1,32) = 13.40, p < 0.01) in the real-world. There were significant age effects for MET/VMET scores (F(1,32) = 19.77, p < 0.0001) and total time (F(1,32) = 11.74, p < 0.05) indicating better performance of the younger group, and a significant environment effect for navigation efficiency (F(1,32) = 7.6, p < 0.01) that was more efficient in the virtual environment. Conclusions This comprehensive, ecological approach in the measurement of performance during tasks reminiscent of complex life situations showed the strengths of using virtual environments in assessing cognitive aspects and limitations of assessing motor aspects of performance. Difficulties by older adults were apparent mainly in the cognitive aspects indicating a need to evaluate them during complex task performance.


2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
N Nante ◽  
L Kundisova ◽  
F Gori ◽  
A Martini ◽  
F Battisti ◽  
...  

Abstract Introduction Changing of life expectancy at birth (LE) over time reflects variations of mortality rates of a certain population. Italy is amongst the countries with the highest LE, Tuscany ranks fifth at the national level. The aim of the present work was to evaluate the impact of various causes of death in different age groups on the change in LE in the Tuscany region (Italy) during period 1987-2015. Material and methods Mortality data relative to residents that died during the period between 1987/1989 and 2013/2015 were provided by the Tuscan Regional Mortality Registry. The causes of death taken into consideration were cardiovascular (CVS), respiratory (RESP) and infective (INF) diseases and cancer (TUM). The decomposition of LE gain was realized with software Epidat, using the Pollard’s method. Results The overall LE gain during the period between two three-years periods was 6.7 years for males, with a major gain between 65-89, and 4.5 years for females, mainly improved between 75-89, &lt;1 year for both sexes. The major gain (2.6 years) was attributable to the reduction of mortality for CVS, followed by TUM (1.76 in males and 0.83 in females) and RESP (0.4 in males; 0.1 in females). The major loss of years of LE was attributable to INF (-0.15 in females; -0.07 in males) and lung cancer in females (-0.13), for which the opposite result was observed for males (gain of 0.62 years of LE). Conclusions During the study period (1987-2015) the gain in LE was major for males. To the reduction of mortality for CVS have contributed to the tempestuous treatment of acute CVS events and secondary CVS prevention. For TUM the result is attributable to the adherence of population to oncologic screening programmes. The excess of mortality for INF that lead to the loss of LE can be attributed to the passage from ICD-9 to ICD-10 in 2003 (higher sensibility of ICD-10) and to the diffusion of multi-drug resistant bacteria, which lead to elevated mortality in these years. Key messages The gain in LE during the period the 1987-2015 was higher in males. The major contribution to gain in LE was due to a reduction of mortality for CVS diseases.


2017 ◽  
Vol 12 (3) ◽  
pp. 339-343 ◽  
Author(s):  
Stephen P Cobley ◽  
Kevin Till

Relative age effects in sports participation highlight the presence of a significant social and developmental inequality. To assess its prevalence, patterning, and size, this study examined participation trends of youth (ages 7–21 years) Rugby League players registered to local community clubs across the North of England ( N = 23,943). Results showed that irrespective of relative age, participation growth occurred from U8 to U12s age categories. However, from U13 to U19s, participation became differentiated with the relatively younger showing earlier and progressively lowering participation proportions (e.g. Q4s – U13–U17 = 24–17%) and were up to 50% less likely to participate (i.e. Q4 vs. Q1 – U15–U16 OR = 0.48 and 0.50). Findings highlight the substantial earlier loss of participation for the relatively younger across youth ages. Player development systems containing inherent selection and differentiation during adolescence are presented as one key process affecting the decision to participate in youth Rugby League.


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