Ponocny; Manning; Ponocny Since then research on the topic has burgeoned around the world. Thumb and testosterone level most cases, however, studies contain the sort of caveat found in the British study. Professional ballers had, on average, the lowest Thumb and testosterone level, and first-team players had lower ratios than reserve players. In some cases, the actual studies do suggest this. Likewise, it is unclear why digit ratio on the right hand should be more responsive than that on the left hand, as is indicated by the greater sex difference on the right than the left.