Relative Age and Maturation Effects Are Separate Constructs

Differences in youth maturation between players can be up to 5 or 6 years.

Relative Age Effect, although significant, only has a maximum of 1 year inter-player variance.

Most of the articles on this blog have dealt with Relative Age Effect alone simply because I only have access to Date of Birth data. This article discusses how Maturation effects are different from RAE, the potential magnitude of these differences and how maturation effects may differ between boys and girls in cricket pathways.  

Relative Age Effect and the effects of early or late Maturation are two different constructs that work independently of each other. They can amplify, negate or conceal the magnitude of a player’s physical and/or psychosocial advantages/disadvantages over another player, resulting in selection/deselection and/or better/worse opportunities.

With RAE, Birth Quarter Q1/Q2s (esp Q1) are selected more in early pathways and Q3/Q4 (esp Q4) are either not selected, potentially dropout or are deselected at further points along the pathway. Conversely Q3/Q4 are more likely to reach super-elite levels. It is proposed that this is due to the heightened levels of challenge they face and is known as the Underdog Hypothesis.

With Maturation in boys early maturers will gain initial benefits of advanced physical strength and psychosocial advantages, but have the same eventual drawback of not being as likely to reach super-elite levels as late maturers. Both early and late maturers represent approximately 15% of players while the remaining 70% are on-time in their maturity timing.

Most Pathway Advantage

RAE: Q1 > Q2 > Q3 > Q4

Maturation: Early > On Time > Late

**Elite Senior Advantage ***

RAE: Q4 > Q3 > Q2 > Q1

Maturation: Late > On Time > Early

* Not necessarily for all disciplines within cricket. Not necessarily for women and girls.

With Maturation in girls the picture is less clear. Physical advantages can be present for early maturers nearer the start of the pathway. However late maturers may have selection advantages later in the pathway as they are perceived to be more athletic in comparison with early maturers who will have gained fat mass.

A player’s Maturity Status is how far along their maturation they are. This can be measured in terms of Percentage of Predicted Adult Height (PPAH) using, for example, the Khamis-Roche method. Boys going through their growth spurt enter a period known as Peak Height Velocity (PHV). Essentially when they are growing fastest. In general boys will enter this phase at around 90% (+- 2%) of PPAH.