Competitive-level differences in the relative age effect among youth table tennis players in China

This cross-sectional study examined the relative age effect (RAE) in Chinese youth table tennis players and compared its magnitude across competitive level, age and sex. Data were obtained from 1,322 athletes aged 12–15 years competing in the 2024–2025 National Youth Table Tennis Championships and Liaoning Provincial Youth Table Tennis Competitions. Athletes were classified into four birth quarters (Q1–Q4). RAE was tested using chi-square analyses, with Cohen’s w and odds ratios (ORs) used to estimate effect magnitude; analyses were stratified by competitive level, age group and sex. A significant RAE was found in the national high-level sample ( P < 0.001), with Q1 athletes over-represented relative to Q4 athletes, whereas no significant RAE was observed in the Liaoning provincial sample. In the national sample, RAE was evident across age groups and was stronger in younger athletes. Sex-stratified analyses suggested earlier RAE expression in females and more pronounced effects in older male age groups. These findings indicate that RAE in Chinese youth table tennis is concentrated in high-level selection contexts and varies by age and sex. Relative age and developmental status should be considered in talent identification.