Larissa F. P. Maciel1, Alexandra Folle1, Mônica C. Flach1, Sara C. Silva1, Walan R. da Silva1, Mariana K. Beirith1, Carine Collet1

1Santa Catarina State University (UDESC), Health and Sport Sciences Center (CEFID), Santa Catarina, Brazil

The Relative Age Effect on Athletes of the Santa Catarina Basketball Federation

Monten. J. Sports Sci. Med. 2022, 11(1), 29-35 | DOI: 10.26773/mjssm.220303


This study analyses the relative age effect (RAE) in basketball athletes, considering the categories (U13, U15, U17, and U19), sex, number of games and average points. The participants were 1,455 Brazilian athletes aged between 9 and 19 who participated in the Santa Catarina State Basketball Championship in the 2018 season. To test the RAE, the Chi-square test (χ2) was performed to compare the observed distribution and expected birth quartiles. To verify the differences between the birth quartiles concerning the average of points and the number of games, One-Way ANOVA with post hoc Bonferroni was applied. The effect size was verified using Eta². Odds Ratios and confidence intervals were calculated for all birth quartiles. In conclusion, it was found that, in the general sample of players participating in the Santa Catarina State Basketball Championship, there was an over-representation of players born in the first two quarters of the year in most of the categories analysed. However, significant dif- ferences were found in the number of games and average points only in male players in the U13 category. These results confirm that the player selection process is negatively biased towards boys born at the end of the year in the U13 category.


relative age effect, youth sport, athlete development, birthday distribution

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Arrieta, H., Torres-Unda, J., Gil, S. M., & Irazusta, J. (2015). Relative age effect and performance in the U16, U18 and U20 European Basketball Championships. Journal of Sports Sciences, 34(1), 1530–1534.

Brazo-Sayavera, J., Martínez-Valencia, M. A., Müller, L., Andronikos, G., & Martindale, R. J. J. (2018). Relative age effects in international age group championships: A study of Spanish track and field athletes. PLoS ONE, 13(4).

Brustio, P. R., Lupo, C., Ungureanu, A. N., Frati, R., Rainoldi, A., & Boccia, G. (2018). The relative age effect is larger in Italian soccer top-level youth categories and smaller in Serie A. PLoS ONE, 13(4), e0196253.

Campos, F. A. D., Pellegrinotti, Í. L., Campos, L. C. B., Dias, T. M. R., & Gómez, M. Á. (2020). Relative Age Effect in the Girls’ Volleyball U18 World Championship. Journal of Human Kinetics, 72(1), 195–202.

Cobley, S., Baker, J., Wattie, N., & McKenna, J. (2009). Annual Age-Grouping and Athlete Development. Sports Medicine, 39(3), 235–256.

De Bosscher, V., & De Rycke, J. (2017). Talent development programmes: a retrospective analysis of the age and support services for talented athletes in 15 nations. European Sport Management Quarterly, 17(5), 590–609.

Delorme, N., & Raspaud, M. (2009). The relative age effect in young French basketball players: A study on the whole population. Scandinavian Journal of Medicine and Science in Sports, 19(2), 235–242.

Donald, S. (2015). Your chi-square test is statistically significant: Now what? Practical Assessment. Research and Evaluation, 20(8), 1–10.

Esteva, S., Drobnic, F., Puigdellivol, J., Serratosa, L., & Chamorro, M. (2006). Fecha de nacimiento y éxito en el baloncesto profesional. Apunts Medicina de l’Esport, 41(149), 25–30.

Ferreira, S. A., Do Nascimento, M. A., Cavazzotto, T. G., Reis Weber, V. M., Tartaruga, M. P., & Queiroga, M. R. (2020). Relative age in female futsal athletes: Implications on anthropometric profile and starter status. Revista Brasileira de Medicina Do Esporte, 26(1), 34–38.

García, M. S., Aguilar, Ó. G., Romero, J. J. F., Lastra, D. F., & Oliveira, G. E. (2014). Relative age effect in lower categories of international basketball. International Review for the Sociology of Sport, 49(5), 526–535.

Hancock, D. J., Adler, A. L., & Côté, J. (2013). A proposed theoretical model to explain relative age effects in sport. European Journal of Sport Science, 13(6), 630–637.

Ibáñez, S. J., Mazo, A., Nascimento, J., & García-Rubio, J. (2018). The Relative Age Effect in under-18 basketball: Effects on performance according to playing position. PLoS ONE, 13(7).

Jackson, R. C., & Comber, G. (2020). Hill on a mountaintop: A longitudinal and cross-sectional analysis of the relative age effect in competitive youth football. Journal of Sports Sciences, 38(11–12), 1352–1358.

Lago-Fuentes, C., Rey, E., Padrón-Cabo, A., Prieto-Troncoso, J., & Garcia-Núñez, J. (2020). The Relative Age Effect in Professional Futsal Players. Journal of Human Kinetics, 72(1), 173–183.

Leite, N., Borges, J., Santos, S., & Sampaio, J. (2013). The relative age effect in school and federative sport in basketball. Revista de Psicología Del Deporte, 22(1), 219–223.

Lidor, R., Arnon, M., Maayan, Z., Gershon, T., & Côté, J. (2014). Relative age effect and birthplace effect in Division 1 female ballgame players-the relevance of sport-specific factors. International Journal of Sport and Exercise Psychology, 12(1), 19–33.

Lupo, C., Boccia, G., Ungureanu, A. N., Frati, R., Marocco, R., & Brustio, P. R. (2019). The beginning of senior career in team sport is affected by the relative age effect. Frontiers in Psychology, 10(June), 1–6.

Maciel, L. F. P., Flach, M. C., Krapp Do Nascimento, R., Dallegrave, E. J., Nascimento, J. V. do, & Folle, A. (2021). Relative Age Effect on basketball: implications for the selection of successful players. RETOS, 42, 266–275.

Oliveira, H. Z., Ribeiro Júnior, D. B., Vianna, J. M., & Werneck, F. Z. (2017). Efeito da idade relativa no campeonato Brasileiro de basquete: Categoria sub-15. Revista Brasileira de Cineantropometria e Desempenho Humano, 19(5), 526–534.

Oliveira, H. Z., Ribeiro Júnior, D. B., Vianna, J. M., Figueiredo, A. J., & Werneck, F. Z. (2019). O que realmente importa para chegar ao alto nível: uma abordagem do efeito da idade relativa no basquetebol brasileiro. Journal of Physical Education, 30, 3079.

Oliveira, H. Z., Ribeiro Júnior, D. B., Werneck, F., & Tavares, F. (2017). Efeito da idade relativa nos jogadores do campeonato brasileiro de basquete da categoria sub-17. Revista Portuguesa de Ciências Do Desporto, 17(1), 90–98.

Ribeiro Júnior, D. B., Lobão, P. H. F., Oliveira, H. Z., Viana, J. M., & Werneck, F. Z. (2020). O efeito da idade relativa em indivíduos normoestaturais e de elevada estatura no basquetebol de base do Brasil. E-Balonmano.Com: Revista de Ciencias Del Deporte, 16(1), 1–10.

Ribeiro Júnior, D. B., Vianna, J. M., Lauria, A. de A., Coelho, E. F., & Werneck, F. Z. (2019). Sports potential modeling of young basketball players: A preliminary analysis. Revista Brasileira de Cineantropometria e Desempenho Humano, 21.

Rubajczyk, K., & Rokita, A. (2018). The Relative Age Effect in Poland’s Elite Youth Soccer Players. Journal of Human Kinetics, 64(1), 265–273.

Rubajczyk, K., Świerzko, K., & Rokita, A. (2017). Doubly disadvantaged? The relative age effect in Poland’s basketball players. Journal of Sports Science and Medicine, 16(2), 280–285.

Saavedra, Y., & Saavedra, J. M. (2020). The Association between Relative Age Effect, Goals Scored, Shooting Effectiveness and the Player’s Position, and her Team’s Final Classification in International Level Women’s Youth Handball. Montenegrin Journal of Sports Science Medicine, 9(1), 1–7.

Sierra-Díaz, M., González-Víllora, S., Pastor-Vicedo, J., & Serra-Olivares, J. (2017). Soccer and Relative Age Effect: A Walk among Elite Players and Young Players. Sports, 5(1), 5.

Torres-Unda, J., Zarrazquin, I., Gravina, L., Zubero, J., Seco, J., Gil, S. M., Gil, J., & Irazusta, J. (2016). Basketball performance is related to maturity and relative age in elite adolescent players. Journal of Strength and Conditioning Research, 30(5), 1325–1332.

Vegara-Ferri, J. M., García-Mayor, J., Pérez, A. M., & Cabezos, H. (2019). Relative age effect in the basketball world championships sub-17, sub-19 and Olympic games of Brazil 2016. Journal of Sport and Health Research, 11(1), 33–42.