# Born to Win? The Hidden Bias of Birthdates in Spanish Orienteering Talent Selection
## 4 Discussion  
The objective of this study was to evaluate the Relative Age Effect (RAE) in elite young male and female orienteers selected to represent Spain in international competitions organised by the IOF. However, prior to these international events, the national selection process exerts significant pressure on athletes and selectors, since the number of spots per sex and  
Figure 4: Odds ratios (_OR_) and 95% confidence intervals (CI) for Q1/Q4 comparisons across international competitions and competitive groups (W: Women; M: Male). Note. (——) No association threshold (OR = 1); (\(\blacksquare\)) OR with 95% CI. Figure 5: Odds ratios (_OR_) and 95% confidence intervals (CI) for S1/S2 comparisons across international competitions and competitive groups (W: Women; M: Male). Note. (——) No association threshold (OR = 1); (\(\blacksquare\)) OR with 95% CI. category is strictly limited. This circumstance compels orienteers to optimise their performance in order to secure their participation. In this context, the results revealed the presence of the RAE among male orienteers in the cadet, youth, junior, and senior categories. These results are consistent with previous findings in other physically demanding individual sports [16; 26; 27; 28; 29] which have reported similar RAE patterns, particularly among male athletes. Although the chi-square analyses did not show significant deviations in the frequency distribution of orienteers from the expected distribution--except for the JWOC--the Z-test for proportions and the odds ratio (OR) analyses (Table 5) revealed that male orienteers born in the first quartile (Q1) showed a two- to four-fold higher representation in international events compared to those born in the third and/or fourth quartile (Q3 and Q4), with statistically significant differences (Figures 1 and 4). This trend was replicated in the distribution by birth semester (Table 5), as significant differences were found in all events for the male sample. Specifically, the probability of selection for an orienteer born in the first semester (S1) was nearly twice as high (OR ranging from 1.61 to 2.19) as for one born in the second semester (S2) (Figures 3 and 5). These results are consistent with previous studies in individual endurance sports, which have also demonstrated a predominance of athletes born in the earlier months of the year [9; 26; 27]. The findings of this study suggest that, regardless of other possible influencing factors (e.g., social or environmental), the selection processes for major international orienteering events are biased in favour of relatively older athletes. As a consequence, numerous young orienteers may face reduced opportunities to accumulate critical sporting experiences and deliberate practice hours [4], potentially undermining their long-term athletic development and limiting their future opportunities within the sport [30]. Accordingly, the meta-analysis by [PERSON] et al. [7] indicated that the risk of the RAE is intensified during mid to late adolescence (ages 14-18), particularly at national-level competitive representation. In the same vein, the findings by [PERSON] et al. [31], which examined the structured development pathway in Rugby League, confirmed that such risk increases as selection processes become more stringent and performance levels rise. Both studies highlight that talent evaluation mechanisms, performance appraisal, and player selection practices play a critical role in perpetuating inequalities associated with the RAE. This phenomenon may help explain the results of the present study, in which a marked RAE was observed among male athletes in the cadet (15-16 years), youth (17-18 years), junior (19-20 years), and senior categories who represented Spain in international competitions. Such overrepresentation may reinforce long-term developmental advantages for early-born athletes by increasing their access to structured training, higher-quality coaching, and performance feedback loops--all of which are key to progression through talent pathways [32].