Digit ratio: comparative analysis between professional volleyball players and medical students

Abstract

Objectives: The ratio of the length of the 2nd digit to the 4th digit of the hand, known as the digit ratio (2D:4D), has been widely studied in health, behavioral, and sports sciences as a potential indicator of prenatal testosterone exposure. This study aimed to compare the 2D:4D ratios of male individuals who are athletically and academically successful and to evaluate whether 2D:4D can serve as a marker for occupational selection, talent identification, and the impact of individual characteristics on job performance. Methods: This study included 32 male professional volleyball players and 39 male medical students. The lengths of the 2nd and 4th digits of both hands were measured using a digital caliper, and the 2D:4D ratio was calculated. The dominant hands of the participants were also recorded for analysis. Results: Intra-group comparisons of the right-hand and left-hand 2D:4D ratios within both the student and volleyball player groups showed no statistically significant differences (p=0.225; p=0.922). Inter-group comparisons of the 2D:4D ratios for the right hand and left hand were also statistically similar (p=0.388; p=0.939). Additionally, the difference between the right-hand and left-hand 2D:4D ratios (Dr-l) did not differ significantly between the groups (p=0.525). Comparisons based on dominant hand preferences revealed no statistically significant findings. Conclusion: This study highlights the need for larger, multicenter studies with more participants to further explore the potential relationship between 2D:4D ratios and occupational or performance traits. We hope this research serves as a foundation for future investigations and provides valuable insights for researchers in this field.

Keywords

• 2D:4D
• digit ratio
• medical students
• performance
• volleyball players

Supporting Institution

None.

Ethical Statement

Ethical approval for this study was granted by Izmir Katip Çelebi University Non-Interventional Research Ethics Committee(November 2022,Approval Number:0587)

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