@article{ref1,
title="Effect of a change in selection year on success in male soccer players",
journal="American journal of human biology",
year="2000",
author="Helsen, Werner F. and Starkes, Janet L. and Van Winckel, Jan",
volume="12",
number="6",
pages="729-735",
abstract="Since 1997 and following the guidelines of the International Football Association, the Belgian Soccer Federation has used January 1st as the start of the selection year. Previously, August 1 was the start. This shift prompted an investigation of changes in birth-date distributions throughout youth categories for 1996-1997 compared to the 1997-1998 competitive years. Birth dates were considered for national youth league players, ages 10-12, 12-14, 14-16, and 16-18 years. Kolmogorov Smirnov tests assessed differences between observed and expected birth-date distributions. Regression analyses examined the relationship between month of birth and number of participants both before and after the August to January shift. <br><br>RESULTS indicated that from 1996 to 1997, youth players born from January to March (the early part of the new selection year) were more likely to be identified as &quot;talented&quot; and to be exposed to higher levels of coaching. In comparison, players born late in the new selection year (August to October) were assessed as &quot;talented&quot; in significantly lower proportions. Specific suggestions are presented to reduce the relative age effect. Am. J. Hum. Biol. 12:729-735, 2000. Copyright 2000 Wiley-Liss, Inc.<p /><p>Language: en</p>",
language="en",
issn="1042-0533",
doi="10.1002/1520-6300(200011/12)12:6<729::AID-AJHB2>3.0.CO;2-7",
url="http://dx.doi.org/10.1002/1520-6300(200011/12)12:6<729::AID-AJHB2>3.0.CO;2-7"
}