Research on Talent Selection Criteria for High School Football Central Defenders based on a Multidimensional Evaluation System

This study is to set up a scientific evaluation system for choosing high school football central defenders. The Delphi method is used to judge 55 preliminary indicators by experts. After verification for consistency (Kendall’s W = 0.638, p < 0.05) and comprehensive analysis, a three-dimensional evaluation framework was constructed with a percentage of physical fitness (37.10%), specialized technical skills (25.03%), and tactical awareness (37.87%) based on weights determined by the Analytic Hierarchy Process. It is advisable that tactical awareness and physical fitness are placed before technical skills. Innovatively, the present study adapted the traditional eleven-a-side match evaluations into 7-a-side small-field matches, which accord with the developmental characteristics of adolescents. Practical testing showed excellent discriminative validity (SD = 8.47) and criterion-related validity (correlation coefficient with coaches’ evaluations: r = 0.82, p < 0.01), which findings should reveal the trend in modern football towards comprehensive defensive aptitudes and therefore are valuable for practical use in youth talent identification.