The prevalence of Relative Age Effect (RAE) was studied among medalists from the World Athletics Championships at U18, U20 and Senior age groups and from the Olympic Games during 2000 to 2022. The specific events examined were the 100, 200, 400, 800, 1500, and 3000/5000 m, long jump, triple jump, high jump and pole vault. Dates of birth from 1,858 outdoor track and field athletes were analysed and further divided into four groups according to the quartile of birth. The RAE was found to be widespread among athletes of both sexes in the U18 and U20 age groups in all examined disciplines. There was no difference between the most successful U18 and U20 athletes (p=0.52). Among senior athletes of both sexes this effect was not detected and the number of 'late-born' athletes in this age group was higher than athletes born in the first three quarters. The prevalence of the RAE across the four discipline groups was found in the U18 and U20 age groups. Additionally, within each age group, the difference between disciplines was statistically significant. In the most successful track and field athletes, RAE is only significant in U18 and U20 age groups. In senior athletes, the number of "late-born" athletes is significant while RAE disappears. These data may be considered when assessing the athletic potential of an individual athlete.