Rob Reed

Rob Reed

The purpose of this blog is to promote changes in policy and practice to ensure ALL players have an EQUAL opportunity by reducing the influence of Relative Age Effect and Maturation on selection and development in the cricket player pathway.

What’s different about this blog?

  • It is specific to cricket
  • Tend to use the number of matches played rather than number of players selected to find a true picture
  • Tend to look at Q1 and Q2 (Sept-Feb) in comparison with Q3 and Q4 (Mar-Aug) rather than just Q1 v Q4 only.

What do we know?

RAE exists in cricket.

RAE exists in pathway cricket in England up to U17 and Australia, up to U17, for men and women.

RAE exists in Eng U19 World Cup squads.

RAE is reversed during County Careers to balance out bias at the start.

RAE exists in Eng ODI selection.

RAE can be up to a 1 year difference in Chronological Age.

Maturation can be up to a 5 year difference in Biological Age.

Maturation effects can be up to 10x those of RAE.

Maturation/Biological Age can be measured (accurately) using the Khamis-Roche method.

5 Ages can affect player selection/development - Chronological, Biological, Relative, Training & Developmental/Cognitive/Behavioural. Joe Eisenmann explains this well.

Why should we care about this?

We should recognise it’s UNFAIR. All sports should have Equality of Opportunity.

It’s COUNTER-PRODUCTIVE. Elite players are derived from a reduced player pool.


  • Q1/Q2/Early Maturers have much lower ‘graduation’ rates
  • Q1/Q2 Eng ODI Players have 33% shorter careers.

What can we do about it?

MONITOR 5 Yr Rolling Averages for Age Groups to target a 25% Quarterly distribution for RAE.

MEASURE. Height/Weight Qtrly. Use % of Predicted Adult Height (Khamis-Roche method) to know Biological Age.

USE Age-ordered shirt numbering in trials.

USE Biological Age & Chronological Age in assessing Fitness & Performance Data.

USE Biobanded match play in addition to age group matches. This offers different and often more appropriate challenges for early or late maturing players.

Why One More Summer?

Kids grow, up to, 3x faster in the Summer than the Winter. Those born in the first half of the academic/sporting year will always have had ‘One More Summer’ to grow when starting a new cricket season.

Who am I?

I’m just a parent (and coach) who has experienced the player pathway and noticed (as many do) how the processes of selection/development favour the ‘bigger’ kids. I wanted to find out more and put some facts and figures together with those observations.

Ignore or act?

While this can be seen as an ‘interesting’ issue and readily understood, little meaningful action or positive change seems to be happening. It has been stuck at the ‘awareness’ level for a number of years.

There are many, many biases and systemic issues in cricket. This blog is a small attempt to counter this one.