## 4 Discussion
### Strengths, Limitations, and Future Research Directions  
One of the main strengths of this study is the use of the actual distribution of births in the Spanish population as a reference for distribution analyses, which enhances the external validity of the findings and reduces the risk of selection bias. Additionally, the sample size is considerably large (N = 34,718), allowing for robust inferences about the distribution of birth quartiles in different competitive and population categories. The inclusion of stratification by sex and competitive level represents a methodological advance over previous studies, aligning with recent research highlighting the importance of gender-specific analyses in RAE studies [9], and allowing for the identification of differences in the manifestation of RAE throughout the sporting development process. However, certain limitations should be noted. Although the study includes longitudinal data on participation in each age group from age 10 to adulthood, a detailed analysis of the rate of sports dropout in relation to relative age was not conducted. This represents a methodological limitation, as identifying dropout patterns by birth quartiles would allow for the evaluation of whether relatively younger athletes face a higher dropout rate at certain stages of competitive development, a phenomenon documented in other sports such as basketball [12] and ice hockey [87]. Furthermore, the present study compares birth distributions in youth and elite groups with the birth distribution in the general Spanish population, rather than with the entire federated population, which could introduce biases in the interpretation of the results. This consideration is relevant, as previous studies have suggested that differences in the participation base may influence the magnitude of RAE at different competition levels [2]. Given the above, future research could address these limitations with complementary methodological approaches. Based on the gaps identified in this study and current research trends, future research could benefit from a mixed-method approach to better understand RAE in orienteering. While quantitative analyses of birth distributions provide valuable insights, qualitative research could help explain why athletes born in later quartiles may face higher dropout rates. Interviews with coaches, athletes, and parents could reveal specific challenges and barriers that relatively younger athletes encounter. Additionally, longitudinal tracking should include not only participation data but also performance metrics and psychological factors such as motivation and perceived competence. Another possible direction for research would be to explore the impact of RAE on sports performance within orienteering, considering different performance indicators or measures of sporting success. The suggestion to compare RAE patterns with Scandinavian countries where orienteering is more established could be expanded to include the analysis of different competition structures and development systems. This cross-cultural comparison should examine how various sporting cultures and organizational approaches might mitigate or exacerbate the RAE. Particular attention should be paid to countries that have implemented specific policies or interventions to address RAE, as these could provide valuable insights for policy recommendations. A recommendation for future studies would be to focus more on orienteering as a sport, as this is truly one of the few studies that specifically analyze the RAE within this discipline. To facilitate the analysis of long-term developmental patterns in local sports systems, it is crucial, as suggested by [PERSON] et al. [88], to continuously collect data on various environmental factors, including the RAE, and compare them across different periods of time. Future research should, in particular, explore the relationship between RAE and athlete dropout rates in orienteering through intervention studies.