In collaboration with Professor Adam L. Kelly and the BCU RAYSD Lab, the KNVB鈥檚 鈥淩elative Age Solutions Project鈥� tackles the well-documented听geboortemaandeffect鈥攚here children born earlier in the more likely selected in youth football鈥攂y moving from awareness to action through a structured, three-part research initiative.听
Part One: A Call to Action听
In April 2025, Professor Adam L. Kelly, Jan Verbeek, and colleagues published a study inviting stakeholders鈥攊ncluding coaches, academics, parents, and policy-makers鈥攖o submit solutions via an open questionnaire. After sifting through 185 submissions, they identified 143 unique proposals. These were sorted into three broad themes: (1) altering observers鈥� behaviour (e.g., increasing coach awareness), (2) implementing selection rules (e.g., entry exemptions), and (3) restructuring competitions (e.g., modifying age bands). While no novel strategies beyond those in existing literature emerged, only two鈥�'cueing age differences鈥� and 鈥榞rouping by chronological and biological age鈥欌�攈ad been empirically tested in football.听
Part Two: Delphi Consensus on Solutions听
In May 2025, the project progressed to an adapted e-Delphi study involving 15 international experts. Each of the 13 proposed lower-order strategies was rated on both effectiveness against relative ages effects and feasibility of implementation. 鈥楻otating cut-off dates鈥� scored highest for direct effectiveness (mean 6.2/9) but was considered less feasible (4.6/9), while 鈥榗ueing differences in age鈥欌�攎aking a player鈥檚 birth month explicitly visible to coaches鈥攇arnered the highest overall viability score (5.8/9), balancing both impact and practicality. Notably, the experts did not reach consensus on many solutions, underscoring the complexity of choosing the right interventions for the right environment.听
Part Three: From Knowledge to Action 鈥� Next Steps and Implications听
The BCU RAYSD Lab and the KNVB now plans to pilot the most promising interventions鈥攗sing a hybrid approach鈥攚ith rigorous evaluation in real-world youth football. Their long鈥憈erm vision is to transition from awareness and proposal stages to tested policy changes that reduce age bias and improve fairness. This project represents a rare, methodical approach to solving or moderating relative age effects in football, moving from theory to practice in Dutch youth football.听
