Robert M Malina1,2, Manuel J Coelho-E-Silva3, António J Figueiredo3, Renaat M Philippaerts4, Norikazu Hirose5, Maria Eugenia Peña Reyes6, Giulio Gilli7, Andrea Benso8, Roel Vaeyens4,9, Dieter Deprez4, Luiz G A Guglielmo10, Rojapon Buranarugsa11. 1. Department of Kinesiology and Health Education, University of Texas, Austin, TX, USA. rmalina@1skyconnect.net. 2. , 10735 FM 2668, Bay City, TX, 77414, USA. rmalina@1skyconnect.net. 3. CIDAF (uid/dtp/04213/2006), Faculty of Sport Science and Physical Education, University of Coimbra, Coimbra, Portugal. 4. Club Brugge KV, Brugge, Belgium. 5. Faculty of Sports Sciences, Waseda University, Saitama, Japan. 6. Instituto Nacional de Antropologia e Historia, Mexico, DF, Mexico. 7. Associazione Italiana di Auxologia, Torino, Italy. 8. Endocrinology, Diabetology and Metabolic Unit, Department of Medical Sciences, University of Turin, Turin, Italy. 9. Department of Movement and Sport Sciences, Ghent University, Ghent, Belgium. 10. Human Performance Research Group, Center for Health and Sport Science, Santa Catarina State University (CEFID/UDESC), Florianópolis, Santa Catarina, Brazil. 11. Department of Physical Education, Faculty of Education, Khon Kaen University, Khon Kaen, Thailand.
Abstract
BACKGROUND: The Tanner-Whitehouse radius-ulna-short bone protocol (TW2 RUS) for the assessment of skeletal age (SA) is widely used to estimate the biological (skeletal) maturity status of children and adolescents. The scale for converting TW RUS ratings to an SA has been revised (TW3 RUS) and has implications for studies of youth athletes in age-group sports. OBJECTIVES: The aim of this study was to compare TW2 and TW3 RUS SAs in an international sample of male youth soccer players and to compare distributions of players by maturity status defined by each SA protocol. METHODS: SA assessments with the TW RUS method were collated for 1831 male soccer players aged 11-17 years from eight countries. RUS scores were converted to TW2 and TW3 SAs using the appropriate tables. SAs were related to chronological age (CA) in individual athletes and compared by CA groups. The difference of SA minus CA with TW2 SA and with TW3 SA was used to classify players as late, average, or early maturing with each method. Concordance of maturity classifications was evaluated with Cohen's Kappa coefficients. RESULTS: For the same RUS score, TW3 SAs were systematically and substantially reduced compared with TW2 SAs; mean differences by CA group ranged from - 0.97 to - 1.16 years. Kappa coefficients indicated at best fair concordance of TW2 and TW3 maturity classifications. Across the age range, 42% of players classified as average with TW2 SA were classified as late with TW3 SA, and 64% of players classified as early with TW2 SA were classified as average with TW3 SA. CONCLUSION: TW3 SAs were systematically lower than corresponding TW2 SAs in male youth soccer players. The differences between scales have major implications for the classification of players by maturity status, which is central to some talent development programs.
BACKGROUND: The Tanner-Whitehouse radius-ulna-short bone protocol (TW2 RUS) for the assessment of skeletal age (SA) is widely used to estimate the biological (skeletal) maturity status of children and adolescents. The scale for converting TW RUS ratings to an SA has been revised (TW3 RUS) and has implications for studies of youth athletes in age-group sports. OBJECTIVES: The aim of this study was to compare TW2 and TW3 RUS SAs in an international sample of male youth soccer players and to compare distributions of players by maturity status defined by each SA protocol. METHODS: SA assessments with the TW RUS method were collated for 1831 male soccer players aged 11-17 years from eight countries. RUS scores were converted to TW2 and TW3 SAs using the appropriate tables. SAs were related to chronological age (CA) in individual athletes and compared by CA groups. The difference of SA minus CA with TW2 SA and with TW3 SA was used to classify players as late, average, or early maturing with each method. Concordance of maturity classifications was evaluated with Cohen's Kappa coefficients. RESULTS: For the same RUS score, TW3 SAs were systematically and substantially reduced compared with TW2 SAs; mean differences by CA group ranged from - 0.97 to - 1.16 years. Kappa coefficients indicated at best fair concordance of TW2 and TW3 maturity classifications. Across the age range, 42% of players classified as average with TW2 SA were classified as late with TW3 SA, and 64% of players classified as early with TW2 SA were classified as average with TW3 SA. CONCLUSION: TW3 SAs were systematically lower than corresponding TW2 SAs in male youth soccer players. The differences between scales have major implications for the classification of players by maturity status, which is central to some talent development programs.
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Authors: Paulo Sousa-E-Silva; Manuel J Coelho-E-Silva; Andre Seabra; Daniela C Costa; Diogo V Martinho; João P Duarte; Tomás Oliveira; João Gonçalves-Santos; Inês Rodrigues; Luis P Ribeiro; António J Figueiredo; Jan M Konarski; Sean P Cumming; Robert M Malina Journal: PLoS One Date: 2022-08-23 Impact factor: 3.752