Relative age effect explained

The term relative age effect (RAE), also known as birthdate effect or birth date effect, is used to describe a bias, evident in the upper echelons of youth sport[1] and academia,[2] where participation is higher amongst those born earlier in the relevant selection period (and lower for those born later in the selection period) than would be expected from the distribution of births. The selection period is usually the calendar year, the academic year or the sporting season.[3]

The difference in maturity often contributes to the effect,[4] with age category, skill level and sport context also impacting the risk of the relative age effect. Mid to late adolescent, regional to nation, popular sports seeing the highest risk, and under 11, recreational, unpopular sports seeing the lowest risk.

The terms month of birth bias and season of birth bias are used to describe similar effect but are fundamentally different. Season of birth examines the influence of different prenatal and perinatal seasonal environmental factors like sunlight, temperature, or viral exposure during gestation, that relate to health outcomes.[5] Conversely, the relative age effect shifts with selection dates[6] moving the advantage with the selection period.[7] With influence from social agents,[8] children born soon after the cut-off date are typically included, and a child born soon before the cut-off date excluded.

In sport

Youth sport participation is often organized into annual age-groups. The IOC,[9] FIFA[10] and the six international football confederations (AFC, CAF, CONCACAF, CONMEBOL, OFC and UEFA[11]) all use 1 January as their administrative cut-off which is most commonly used but, 1 September is used in the UK,[12] like many other locations around the world.[13] This grouping can be seen in the first graph showing the distribution of births, by month, for the European Union over the ten years from 2000 to 2009. The birth rate correlates closely with the number of days in a month with a slight increase in the summer months. The second graph, by the month, shows the birth distribution of over 4,000 players involved in the qualifying squads for U17, U19 and U21 tournaments organised by UEFA in 2010–11.

This declining distribution from the beginning of the year for professional athlete participation has been seen in sports like: association football,[14] baseball,[15] cricket,[16] gymnastics,[17] handball,[18] ice hockey,[19] rugby league,[20] running,[21] skiing,[22] swimming,[17] tennis,[23] and the Youth Olympic Games,[24] as well as non-physical sports like shooting.[25]

Malcolm Gladwell's book Outliers: The Story of Success and the book SuperFreakonomics by Steven Levitt and Stephen Dubner, popularised the issue in respect of Canadian ice-hockey players, European football players, and US Major League baseball players.

Contributing factors

Relative age effects are caused by birthdate eligibility rules but can be affected by parents, coaches and athletes through other mechanisms.[26] The Pygmalion effect, Galatea effect, and Matthew effect are examples of effects which impact player motivation.[27]

In addition to these social factors contextual differences change the distribution with decreased effects in female sports,[28] [29] unpopular sports,[30] at different ages,[31] individual sports,[32] or sports with a lower reliance on body size,[33] with an expected increased effect in male sports, popular sports, or competitive sports. The sports popularity in a geographical or cultural area will affect the relative age distribution relative, with examples seen in volleyball[34] and American football.[35]

The early maturation levels giving physical advantages to first quarter individuals can create the bias, seen in players' height in basketball,[36] dominant hand in tennis,[37] or size in a cricket position,[38] but physical size isn't always the cause.[39] Older individuals also gain more competence and self-efficacy,[40] increasing the performance gap. These advantages lead to increased dropout rates for Q1 births.[41] [42] However, the bias for sports where height and mass impedes flexibility, rotational speed and the strength to mass ratio, maturational delay may be preferred as seen in gymnastics.[43]

With an adult group the relative age has the opposite meaning,[44] as performance declines in age,[45] and is more significant with more physically demanding sports,[46] depending on what age the average peak performance level is, in that sport.[47] The "underdog effect" has shown that those late birth individuals may see better chances[48] if they are selected to play, with the advantage decreasing after selection.[49]

Playing position, federation membership, and individual and team performance also contribute to the effect, with older players having a higher risk of injury.[50]

Reducing the relative age effect

Various methods have been suggested and tested to reduce the relative age effect like moving the cut off dates, expanding the age group range,[51] birthdate quotas for the players,[52] the average team age (ATA) method for eligibility,[53] [54] or grouping by height and weight. Some methods have struggled to find success due to the effect moving with selection dates. Making the relative age known to the individuals in the environment have shown less bias in talent identification reducing the relative age effect.[55]

Birthday banding,[56] and re-calculating scores based on relative age,[57] are other methods used to reduce the effects,[58] with bio-banding seeing the most research, showing benefit to early and late maturing players,[59] both in academy football[60] and in recreational football.[61] Bio-banding can help promote appropriate training loads and reduce injury risk,[62] while increasing technical demands from players,[63] however, sports already categorized by maturation metrics like Judo,[64] may not see those effects. More longitudinal studies are needed,[65] alongside more reliable ways to band individuals,[66] as biological, psychological and social development doesn't progress in synchrony,[67] creating different imbalances in the groups.

In education

The Academic year is decided by education authorities with August or September being common cut-off dates in the Northern Hemisphere and February or March cut-off dates in the Southern Hemisphere.

The third graph illustrates the relative age effect in graduations from the University of Oxford over a 10-year period, which has also been seen in UK Nobel laureates.[68]

The relative age effect and reversal effect are evident in education,[69] with older students on average scoring higher marks, getting into more gifted and talented programs,[70] and being more likely to attend higher education[71] in academic schools over vocational schools,[72] not necessarily due to higher intelligence.[73] The Matthew effect again plays a role, as the skills learned early in education compound over time, increasing the advantage, with older students becoming more likely to take up leadership roles. However, like in sport, the effect diminishes over time after middle school,[74] and those born later in the year perform better in university education.[75]

In leadership positions

A relative age effect has also been observed in the context of leadership. An over-representation starts in high-school leadership activities such as sports team captain or club president.[76] Then in adult life, this over-representation has been observed in top managerial positions (CEOs of S&P 500 companies),[77] and in top political positions, both in the USA (senators and representatives),[78] and in Finland (MPs).[79]

Seasonal birth effect

Seasonal birth in humans varies, and alongside the relative age effect the epidemiology of seasonal births show over-representations in health conditions like ADHD[80] and schizophrenia,[81] [82] with one study finding "that higher school starting age lowers the propensity to commit crime at young ages."[83] However, other studies failed to replicate relative age effects on temperament, mood, or physical development.

Obesity has been linked to season of birth with increased chances,[84] potentially due to surrounding temperature at birth,[85] with winter and spring having the highest correlation, but physical inactivity is still a larger risk factor.[86]

Summer babies have increased chances of specific learning difficulties,[5] [87] and winter and spring babies related to schizophrenia and mania/bipolar disorder. Schizoaffective disorder can be related to December-March births, major depression to March-May births, and autism to March births.[88]

Increased rates in seasonal affective disorder relate to the influence of seasonal birth in humans.[89]

Notes and References

  1. Web site: Birthdate Effects: A Review of the Literature from 1990-on. 8 November 2021. Cambridgeassessment.org.uk.
  2. Web site: When You Are Born Matters: The Impact of Date of Birth on Child Cognitive Outcomes in England. Claire Crawford. Lorraine Dearden. Costas Meghir. 2045-6557. Cee.lse.ac.uk. 8 November 2021. 28 January 2012. https://web.archive.org/web/20120128200748/http://cee.lse.ac.uk/ceedps/ceedp93.pdf. dead.
  3. Book: Birth Advantages and Relative Age Effects in Sport: Exploring Organizational Structures and Creating Appropriate Settings. 2021-06-04. Routledge. 978-1-003-16357-2. Kelly. Adam L.. New York. 10.4324/9781003163572. 241069004. Côté. Jean. Jeffreys. Mark. Turnnidge. Jennifer.
  4. Web site: 23 April 2016. Long-term relative age effect: Evidence from Italian football. 23 April 2016. VoxEU.org.
  5. Barry. H.. Bary. H.. 1961. Season of birth. An epidemiological study in psychiatry. Archives of General Psychiatry. 5. 292–300. 10.1001/archpsyc.1961.01710150074012. 0003-990X. 13687345.
  6. Helsen. Werner F.. Starkes. Janet L.. Van Winckel. Jan. 2000-11-01. Effect of a change in selection year on success in male soccer players. American Journal of Human Biology. 12. 6. 729–735. 10.1002/1520-6300(200011/12)12:6<729::AID-AJHB2>3.0.CO;2-7. 1520-6300. 11534065. 24013421 .
  7. Musch. Jochen. Hay. Roy. 1999-03-01. The Relative Age Effect in Soccer: Cross-Cultural Evidence for a Systematic Discrimination against Children Born Late in the Competition Year. Sociology of Sport Journal. en-US. 16. 1. 54–64. 10.1123/ssj.16.1.54. 0741-1235.
  8. Hancock. David J.. Adler. Ashley L.. Côté. Jean. 2013. A proposed theoretical model to explain relative age effects in sport. European Journal of Sport Science. 13. 6. 630–637. 10.1080/17461391.2013.775352. 1536-7290. 24251740. 1974/14350. 32336640. free.
  9. Web site: 29 July 2021. Olympic Documents - Athletes, Olympic Games, IOC and More.
  10. Web site: FIFA.com. https://web.archive.org/web/20130330161133/http://www.fifa.com/mm/document/tournament/competition/01/95/44/82/regulationsfu20wcturkey2013%5fee.pdf. 8 November 2021. 2013-03-30.
  11. Web site: https://www.uefa.com/MultimediaFiles/Download/Regulations/competitions/Regulations/01/65/31/62/1653162_DOWNLOAD.pdf. Uefa.com. 8 November 2021. 21 June 2018. https://web.archive.org/web/20180621143622/https://www.uefa.com/MultimediaFiles/Download/Regulations/competitions/Regulations/01/65/31/62/1653162_DOWNLOAD.pdf. dead.
  12. Cobley. Stephen. Baker. Joseph. Wattie. Nick. McKenna. Jim. 2009. Annual age-grouping and athlete development: a meta-analytical review of relative age effects in sport. Sports Medicine (Auckland, N.Z.). 39. 3. 235–256. 10.2165/00007256-200939030-00005. 0112-1642. 19290678. 32633686.
  13. Wattie. Nick. Cobley. Stephen. Baker. Joseph. 2008. Towards a unified understanding of relative age effects. Journal of Sports Sciences. 26. 13. 1403–1409. 10.1080/02640410802233034. 0264-0414. 18825541. 11241958.
  14. Ashworth. John. Heyndels. Bruno. 1 August 2007. Selection Bias and Peer Effects in Team Sports: The Effect of Age Grouping on Earnings of German Soccer Players. Journal of Sports Economics. en. 8. 4. 355–377. 10.1177/1527002506287695. 154330153. 1527-0025.
  15. Herring. Chad H.. Beyer. Kyle S.. Fukuda. David H.. 2021. Relative Age Effects as Evidence of Selection Bias in Major League Baseball Draftees (2013–2018). The Journal of Strength & Conditioning Research. en-US. 35. 3. 644–651. 10.1519/JSC.0000000000003951. 33470599. 231651477. 1064-8011.
  16. Edwards. S.. 1994-07-21. Born too late to win?. Nature. 370. 6486. 186. 10.1038/370186a0. 0028-0836. 8028664. 1994Natur.370..186E. 5420946. free.
  17. Baxter-Jones. A. D.. 1995. Growth and development of young athletes. Should competition levels be age related?. Sports Medicine (Auckland, N.Z.). 20. 2. 59–64. 10.2165/00007256-199520020-00001. 0112-1642. 7481282. 45304762.
  18. Rubia. Alfonso de la. Bjørndal. Christian Thue. Sánchez-Molina. Joaquín. Yagüe. José María. Calvo. Jorge Lorenzo. Maroto-Izquierdo. Sergio. 2020. The relationship between the relative age effect and performance among athletes in World Handball Championships. PLOS ONE. 15. 3. e0230133. 10.1371/journal.pone.0230133. 1932-6203. 7098603. 32214322. 2020PLoSO..1530133R. free.
  19. Addona. Vittorio. Yates. Philip A.. 15 October 2010. A Closer Look at the Relative Age Effect in the National Hockey League. Journal of Quantitative Analysis in Sports. en. 6. 4. 10.2202/1559-0410.1227. 120240341. 1559-0410.
  20. Till. K.. Cobley. S.. Wattie. N.. O'Hara. J.. Cooke. C.. Chapman. C.. 2010. The prevalence, influential factors and mechanisms of relative age effects in UK Rugby League. Scandinavian Journal of Medicine & Science in Sports. en. 20. 2. 320–329. 10.1111/j.1600-0838.2009.00884.x. 19486487. 33840698. 1600-0838.
  21. Romann. Michael. Cobley. Stephen. 6 April 2015. Relative Age Effects in Athletic Sprinting and Corrective Adjustments as a Solution for Their Removal. PLOS ONE. en. 10. 4. e0122988. 10.1371/journal.pone.0122988. 1932-6203. 4386815. 25844642. 2015PLoSO..1022988R. free.
  22. Romann. Michael. Fuchslocher. Jörg. 1 April 2014. Survival and Success of the Relatively Oldest in Swiss Youth Skiing Competition. International Journal of Sports Science & Coaching. en. 9. 2. 347–356. 10.1260/1747-9541.9.2.347. 144244440. 1747-9541.
  23. Ulbricht. Alexander. Fernandez-Fernandez. Jaime. Mendez-Villanueva. Alberto. Ferrauti. Alexander. 2015. The Relative Age Effect and Physical Fitness Characteristics in German Male Tennis Players. Journal of Sports Science & Medicine. 14. 3. 634–642. 1303-2968. 4541129. 26336351.
  24. Raschner. Christian. Müller. Lisa. Hildebrandt. Carolin. 1 December 2012. The role of a relative age effect in the first winter Youth Olympic Games in 2012. British Journal of Sports Medicine. en. 46. 15. 1038–1043. 10.1136/bjsports-2012-091535. 0306-3674. 22976907. 37476293.
  25. Delorme. Nicolas. Raspaud. Michel. 1 August 2009. Is there an influence of relative age on participation in non-physical sports activities? The example of shooting sports. Journal of Sports Sciences. 27. 10. 1035–1042. 10.1080/02640410902926438. 0264-0414. 19847687. 1624812.
  26. Thompson. Angus H.. Barnsley. Roger H.. Stebelsky. George. 1991-06-01. "Born to Play Ball" The Relative Age Effect and Major League Baseball. Sociology of Sport Journal. en-US. 8. 2. 146–151. 10.1123/ssj.8.2.146. 0741-1235.
  27. Harter. Susan. 1978. Effectance Motivation Reconsidered. Toward a Developmental Model. Human Development. english. 21. 1. 34–64. 10.1159/000271574. 0018-716X.
  28. Abel. Ernest L.. Kruger. Michael M.. Pandya. Kalyani. August 2011. A relative age effect in men's but not women's professional baseball: 1943-1954. Psychological Reports. 109. 1. 285–288. 10.2466/05.PR0.109.4.285-288. 0033-2941. 22049668. 23937679.
  29. Romann. Michael. Fuchslocher. Jörg. 2014-06-01. The Need to Consider Relative Age Effects in Women's Talent Development Process. Perceptual and Motor Skills. en. 118. 3. 651–662. 10.2466/30.10.PMS.118k24w8. 25068738. 207391641. 0031-5125.
  30. Wattie. Nick. A historical examination of relative age effects in Canadian hockey players.. International Journal of Sport Psychology.
  31. Delorme. N.. Chalabaev. A.. Raspaud. M.. 2011. Relative age is associated with sport dropout: evidence from youth categories of French basketball: Relative age effect and dropout. Scandinavian Journal of Medicine & Science in Sports. en. 21. 1. 120–128. 10.1111/j.1600-0838.2009.01060.x. 20136758. 20611526.
  32. Baker. Joseph. Janning. Christina. Wong. Harmonie. Cobley. Stephen. Schorer. Jörg. 2014. Variations in relative age effects in individual sports: skiing, figure skating and gymnastics. European Journal of Sport Science. 14. Suppl 1 . S183–190. 10.1080/17461391.2012.671369. 1536-7290. 24444205. 205918608.
  33. Gil. Susana M.. Bidaurrazaga-Letona. Iraia. Larruskain. Jon. Esain. Izaro. Irazusta. Jon. 2021. The relative age effect in young athletes: A countywide analysis of 9-14-year-old participants in all competitive sports. PLOS ONE. 16. 7. e0254687. 10.1371/journal.pone.0254687. 1932-6203. 8284647. 34270609. 2021PLoSO..1654687G. free.
  34. Musch. Jochen. Grondin. Simon. 2001. Unequal Competition as an Impediment to Personal Development: A Review of the Relative Age Effect in Sport. Developmental Review. 21. 2. 147–167. 10.1006/drev.2000.0516. 0273-2297.
  35. Stanaway. Kimberly B.. Hines. Terence M.. 1995-12-01. Lack of a Season of Birth Effect among American Athletes. Perceptual and Motor Skills. en. 81. 3. 952–954. 10.2466/pms.1995.81.3.952. 144431104. 0031-5125.
  36. Delorme. N.. Raspaud. M.. 2009. The relative age effect in young French basketball players: a study on the whole population. Scandinavian Journal of Medicine & Science in Sports. en. 19. 2. 235–242. 10.1111/j.1600-0838.2008.00781.x. 18298612. 126598. 1600-0838.
  37. Loffing. Florian. Schorer. Jörg. Cobley. Steve P.. 2010-06-01. Relative Age Effects are a developmental problem in tennis: but not necessarily when you're left-handed!. High Ability Studies. 21. 1. 19–25. 10.1080/13598139.2010.488084. 145150287. 1359-8139.
  38. Côté. Jean. Macdonald. Dany J.. Baker. Joseph. Abernethy. Bruce. 2006. When "where" is more important than "when": birthplace and birthdate effects on the achievement of sporting expertise. Journal of Sports Sciences. 24. 10. 1065–1073. 10.1080/02640410500432490. 0264-0414. 17115521. 1974/14413. 12638438. free.
  39. Sherar. Lauren B.. Baxter-Jones. Adam D. G.. Faulkner. Robert A.. Russell. Keith W.. 2007. Do physical maturity and birth date predict talent in male youth ice hockey players?. Journal of Sports Sciences. 25. 8. 879–886. 10.1080/02640410600908001. 0264-0414. 17474041. 24530414.
  40. Heffernan. Colleen J.. 1988. Social foundations of thought and action: A social cognitive theory, Albert Bandura Englewood Cliffs, New Jersey: Prentice Hall, 1986, xiii + 617 pp. Hardback. US$39.50.. Behaviour Change. en. 5. 1. 37–38. 10.1017/S0813483900008238. 0813-4839.
  41. García. Miguel Saavedra. Aguilar. Óscar Gutiérrez. Romero. Juan J Fernández. Lastra. David Fernández. Oliveira. Gabriel Eiras. 2014-10-01. Relative age effect in lower categories of international basketball. International Review for the Sociology of Sport. en. 49. 5. 526–535. 10.1177/1012690212462832. 145132099. 1012-6902.
  42. Delorme. Nicolas. Boiché. Julie. Raspaud. Michel. 1 May 2010. Relative age and dropout in French male soccer. Journal of Sports Sciences. 28. 7. 717–722. 10.1080/02640411003663276. 0264-0414. 20480428. 6176116.
  43. Baxter-Jones. Adam D.G.. 1995. Growth and Development of Young Athletes: Should Competition Levels be Age Related?. Sports Medicine. en. 20. 2. 59–64. 10.2165/00007256-199520020-00001. 7481282. 45304762. 0112-1642.
  44. Medic. Nikola. Starkes. Janet L.. Young. Bradley W.. 2007. Examining relative age effects on performance achievement and participation rates in Masters athletes. Journal of Sports Sciences. 25. 12. 1377–1384. 10.1080/02640410601110128. 0264-0414. 17786690. 6530220.
  45. Baker. Joseph. Deakin. Janice. Horton. Sean. Pearce. G. William. 2007. Maintenance of skilled performance with age: a descriptive examination of professional golfers. Journal of Aging and Physical Activity. 15. 3. 300–317. 10.1123/japa.15.3.300. 1063-8652. 17724396.
  46. Bortz. W. M.. 1996. How fast do we age? Exercise performance over time as a biomarker. The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences. 51. 5. M223–225. 10.1093/gerona/51a.5.m223. 1079-5006. 8808993. free.
  47. Starkes. Janet. Aging and the retention of sport expertise.. International Journal of Sport Psychology.
  48. Schorer. J.. Cobley. S.. Büsch. D.. Bräutigam. H.. Baker. J.. 2009. Influences of competition level, gender, player nationality, career stage and playing position on relative age effects. Scandinavian Journal of Medicine & Science in Sports. en. 19. 5. 720–730. 10.1111/j.1600-0838.2008.00838.x. 18627551. 1084598. 1600-0838. free.
  49. Vaeyens. Roel. Philippaerts. Renaat M.. Malina. Robert M.. 2005. The relative age effect in soccer: a match-related perspective. Journal of Sports Sciences. 23. 7. 747–756. 10.1080/02640410400022052. 0264-0414. 16195025. 19513513.
  50. Wattie. Nick. Cobley. Stephen. Macpherson. Alison. Howard. Andrew. Montelpare. William J.. Baker. Joseph. 2007. Injuries in Canadian youth ice hockey: the influence of relative age. Pediatrics. 120. 1. 142–148. 10.1542/peds.2006-2672. 1098-4275. 17606571. 24189760.
  51. Boucher. J. The novem system: A practical solution to age grouping.. Cahper Journal.
  52. APA PsycNet. 2021-11-12. Canadian Journal of Behavioural Science . 1988. 20. 2. 167–176. 10.1037/h0079927. Barnsley. Roger H.. Thompson. A. H..
  53. Book: Verbeek. J.. Lawrence. S.. van der Breggen. J.. Kelly. A.. Jonker. L.. Birth Advantages and Relative Age Effects in Sport . The average team age method and its potential to reduce relative age effects.. Routledge. 2021 . 107–124 . 10.4324/9781003163572-10 . 9781003163572 . 234878601 .
  54. Helsen. Werner F.. Starkes. Janet L.. Van Winckel. Jan. 1998. The influence of relative age on success and dropout in male soccer players. American Journal of Human Biology. 10. 6. 791–798. 10.1002/(SICI)1520-6300(1998)10:6<791::AID-AJHB10>3.0.CO;2-1. 1520-6300. 28561412. 32958835 .
  55. Mann. David. Age-ordered shirt numbering reduces the selection bias associated with the relative age effect. Journal of Sports Sciences. 2017. 35. 8. 784–790. 10.1080/02640414.2016.1189588. 27238077. 30301449. free. 1871.1/8699ca89-7bc5-4be7-b61a-bf8841dc3106. free.
  56. Kelly. Adam L.. Jackson. Daniel T.. Taylor. Josh J.. Jeffreys. Mark A.. Turnnidge. Jennifer. 2020. "Birthday-Banding" as a Strategy to Moderate the Relative Age Effect: A Case Study Into the England Squash Talent Pathway. Frontiers in Sports and Active Living. 2. 573890. 10.3389/fspor.2020.573890. 2624-9367. 7739587. 33345136. free.
  57. Romann. M. Cobley. S. 2015. Relative Age Effects in Athletic Sprinting and Corrective Adjustments as a Solution for Their Removal. PLOS ONE. 10. 4. e0122988. 2015PLoSO..1022988R. 10.1371/journal.pone.0122988. 4386815. 25844642. free.
  58. Reeves. M. Enright. K. Dowling. J. Roberts. S. 2018. Stakeholders' understanding and perceptions of bio-banding in junior-elite football training. Soccer & Society. 19. 1166–1182. 10.1080/14660970.2018.1432384. 148894870.
  59. Hill. Megan. Spencer. Amy. McGee. Darragh. Scott. Sam. Frame. Malcolm. Cumming. Sean P.. 2020-05-18. The psychology of bio-banding: a Vygotskian perspective. Annals of Human Biology. 47. 4. 328–335. 10.1080/03014460.2020.1797163. 0301-4460. 32674664. 220607644.
  60. Bradley. Ben. Johnson. David. Hill. Megan. McGee. Darragh. Kana-Ah. Adam. Sharpin. Callum. Sharp. Peter. Kelly. Adam. Cumming. Sean P.. Malina. Robert M.. 2019. Bio-banding in academy football: player's perceptions of a maturity matched tournament. Annals of Human Biology. 46. 5. 400–408. 10.1080/03014460.2019.1640284. 1464-5033. 31288575. 195871072.
  61. Romann. Michael. Lüdin. Dennis. Born. Dennis-Peter. 2020-05-12. Bio-banding in junior soccer players: a pilot study. BMC Research Notes. 13. 1. 240. 10.1186/s13104-020-05083-5. 1756-0500. 7216411. 32398110 . free .
  62. Malina. Robert M.. Cumming. Sean P.. Rogol. Alan D.. Coelho-E-Silva. Manuel J.. Figueiredo. Antonio J.. Konarski. Jan M.. Kozieł. Sławomir M.. 2019. Bio-Banding in Youth Sports: Background, Concept, and Application. Sports Medicine. 49. 11. 1671–1685. 10.1007/s40279-019-01166-x. 1179-2035. 31429034. 201058305.
  63. Abbott. Will. Williams. Stuart. Brickley. Gary. Smeeton. Nicholas J.. 2019-08-14. Effects of Bio-Banding upon Physical and Technical Performance during Soccer Competition: A Preliminary Analysis. Sports . 7. 8. E193. 10.3390/sports7080193. 2075-4663. 6722793. 31416230. free.
  64. Giudicelli. Bruno B.. Luz. Leonardo G. O.. Sogut. Mustafa. Massart. Alain G.. Júnior. Arnaldo C.. Figueiredo. António J.. 2020-01-05. Bio-Banding in Judo: The Mediation Role of Anthropometric Variables on the Maturation Effect. International Journal of Environmental Research and Public Health. 17. 1. E361. 10.3390/ijerph17010361. 1660-4601. 6981667. 31948074. free.
  65. Stănilă. Alexandra Mihaela. Lupşa. Marius Matichescu. Stănilă. Cătălin. 2020-09-01. BIO-BANDING from concept to practice in sports. Timisoara Physical Education and Rehabilitation Journal. en. 13. 24. 19–24. 10.2478/tperj-2020-0003. 220772237. free.
  66. Reeves. Matthew J.. Enright. Kevin J.. Dowling. Jack. Roberts. Simon J.. 2018-11-17. Stakeholders' understanding and perceptions of bio-banding in junior-elite football training. Soccer & Society. 19. 8. 1166–1182. 10.1080/14660970.2018.1432384. 148894870. 1466-0970.
  67. Cumming. Sean P.. Lloyd. Rhodri S.. Oliver. Jon L.. Eisenmann. Joey C.. Malina. Robert M.. 2017. Bio-banding in Sport: Applications to Competition, Talent Identification, and Strength and Conditioning of Youth Athletes. Strength & Conditioning Journal. en-US. 39. 2. 34–47. 10.1519/SSC.0000000000000281. 10369/8460. 1524-1602.
  68. Fukunaga. Hisanori. Taguri. Masataka. Morita. Satoshi. 2013-10-01. Relative age effect on Nobel laureates in the UK. JRSM Short Reports. en. 4. 10. 2042533313492514. 10.1177/2042533313492514. 2042-5333. 3831864. 24319580.
  69. Jeronimus. Bertus F. Stavrakakis. Nikolaos. Veenstra. René. Oldehinkel. Albertine J. 2015. Relative Age Effects in Dutch Adolescents: Concurrent and Prospective Analyses. PLOS ONE. 10. 6. e0128856. 10.1371/journal.pone.0128856. 4468064. 26076384. 2015PLoSO..1028856J. free.
  70. APA PsycNet. 2021-11-15. Journal of Educational Psychology. May 2009. 101. 2. 520–528. 10.1037/a0013845. Cobley. Stephen. McKenna. Jim. Baker. Joeseph. Wattie. Nick.
  71. Bedard. K. Dhuey. E. Elizabeth Dhuey. 2006. The Persistence of Early Childhood Maturity: International Evidence of Long-Run Age Effects. The Quarterly Journal of Economics. 121. 4. 1437–72. 10.1093/qje/121.4.1437. 25098831.
  72. Ponzo. Michela. Scoppa. Vincenzo. 2014. The long-lasting effects of school entry age: Evidence from Italian students. Journal of Policy Modeling. 36. 3. 578–99. 10.1016/j.jpolmod.2014.04.001.
  73. Shearer. E.. 1967-12-01. The Effect of Date of Birth on Teachers' Assessments of Children. Educational Research. 10. 1. 51–56. 10.1080/0013188670100104. 0013-1881.
  74. Hauck. Anne Logan. Finch. A. J.. 1993. The effect of relative age on achievement in middle school. Psychology in the Schools. en. 30. 1. 74–79. 10.1002/1520-6807(199301)30:1<74::AID-PITS2310300112>3.0.CO;2-E. 1520-6807.
  75. Russell. R. J. H.. Startup. M. J.. 1986-01-01. Month of birth and academic achievement. Personality and Individual Differences. en. 7. 6. 839–846. 10.1016/0191-8869(86)90082-6. 0191-8869.
  76. 10.1016/j.econedurev.2006.08.005 . What makes a leader? Relative age and high school leadership . Economics of Education Review . 27 . 2 . 173–83 . 2008 . Dhuey . Elizabeth . Lipscomb . Stephen . 10.1.1.394.8881 .
  77. 10.1016/j.econlet.2012.08.017 . The relative-age effect and career success: Evidence from corporate CEOs . Economics Letters . 117 . 3 . 660–2 . 2012 . Du . Qianqian . Gao . Huasheng . Levi . Maurice D .
  78. 10.1111/rssa.12154 . Born leaders: Political selection and the relative age effect in the US Congress . Journal of the Royal Statistical Society, Series A (Statistics in Society). 179 . 3 . 809–29 . 2016 . Muller . Daniel . Page . Lionel . 124379974 . free .
  79. Web site: Gender Specific Relative Age Effects in Politics and Football. PDF. Doria.fi. 8 November 2021.
  80. Morrow. R. L. Garland. E. J. Wright. J. M. MacLure. M. Taylor. S. Dormuth. C. R. 2012. Influence of relative age on diagnosis and treatment of attention-deficit/hyperactivity disorder in children. Canadian Medical Association Journal. 184. 7. 755–62. 10.1503/cmaj.111619. 3328520. 22392937.
  81. Davies. G. Welham. J. Chant. D. Torrey. E. F. McGrath. J. 2003. A Systematic Review and Meta-analysis of Northern Hemisphere Season of Birth Studies in Schizophrenia. Schizophrenia Bulletin. 29. 3. 587–93. 10.1093/oxfordjournals.schbul.a007030. 14609251. free.
  82. Web site: Season of Birth of Students Receiving Special Education Services Under a Diagnosis of Emotional and Behavioral Disorder. 8 November 2021. Eduratio.be.
  83. Landersø. Rasmus. Nielsen. Helena Skyt. Simonsen. Marianne. 2017. School Starting Age and the Crime-age Profile. The Economic Journal. 127. 602. 1096–118. 10.1111/ecoj.12325. 2984362. 155576753.
  84. Hillman. R. W.. Conway. H. C.. 1972. Season of birth and relative body weight. The American Journal of Clinical Nutrition. 25. 3. 279–281. 10.1093/ajcn/25.3.279. 0002-9165. 5011910. free.
  85. Phillips. D. I.. Young. J. B.. 2000. Birth weight, climate at birth and the risk of obesity in adult life. International Journal of Obesity and Related Metabolic Disorders. 24. 3. 281–287. 10.1038/sj.ijo.0801125. 10757620. 24898098.
  86. Wattie. Nick. Ardern. Chris I.. Baker. Joseph. 2008. Season of birth and prevalence of overweight and obesity in Canada. Early Human Development. 84. 8. 539–547. 10.1016/j.earlhumdev.2007.12.010. 0378-3782. 18280062.
  87. Diamond. Grace H.. 1983-03-01. The Birthdate Effect: A Maturational Effect?. Journal of Learning Disabilities. en. 16. 3. 161–164. 10.1177/002221948301600306. 6864105. 28321784. 0022-2194.
  88. Torrey. E. F.. Miller. J.. Rawlings. R.. Yolken. R. H.. 1997-11-07. Seasonality of births in schizophrenia and bipolar disorder: a review of the literature. Schizophrenia Research. 28. 1. 1–38. 10.1016/s0920-9964(97)00092-3. 0920-9964. 9428062. 54259124. free.
  89. Levitan. Robert D.. Masellis. Mario. Lam. Raymond W.. Kaplan. Allan S.. Davis. Caroline. Tharmalingam. Subi. Mackenzie. Bronwyn. Basile. Vincenzo S.. Kennedy. James L.. 2006. A birth-season/DRD4 gene interaction predicts weight gain and obesity in women with seasonal affective disorder: A seasonal thrifty phenotype hypothesis. Neuropsychopharmacology. 31. 11. 2498–2503. 10.1038/sj.npp.1301121. 0893-133X. 16760922. 35504875. free.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Relative age effect".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.