skip navigation

Birthday bias: Understanding relative age effect in youth hockey

08/16/2017, 11:00am MDT
By Michael Rand

Malcolm Gladwell’s 2008 book “Outliers” brought widespread attention to a phenomenon known as “relative age effect,” used to describe a bias toward members of a cohort or team born earlier than peers in the same group. Gladwell emphasized his point by using examples from Canadian junior hockey.

But if that was the first time you had heard about relative age effect, or at least the bias that it describes, you probably haven’t spent much time in youth hockey. Recognizing – and trying to counteract – relative age effect in hockey and other youth sports has been going on far longer than just the past decade or so.

Studying it within USA Hockey has led to conclusions on how to combat it, said Ken Martel, technical director for USA Hockey’s American Development Model. As with many things in youth sports, though, there are no perfect one-size-fits-all answers.

The impact

In the USA Hockey system, youth players are classified by their year of birth. But an 8U player born in, say, January 2009 is several months older than peers born toward the end of that year.

At that age, being almost a full year older than other players on your team can be a huge advantage in both size and current skill. And that early age advantage can unfairly separate players.

“Historically with youth sports, the kids who make the ‘A’ team are the ones that are maybe a little older – 6 months more than the one born in December,” Martel said. “When you group teams that way, that ‘A’ team gets the best coach and the best ice time. It starts to become a self-fulfilling prophecy that those are the best players.”

Keeping kids in hockey

The flip side is that youth hockey players born in later months might get short-changed simply because they aren’t as big or haven’t had the extra months to catch up skill-wise. As a result, they might get placed on a lower-priority team or be under-coached and – in the worst-case scenario – lose interest in hockey and quit because they don’t think they will succeed.

That’s the danger of clubs operating with a compete-to-win, “peak-by-the-weekend” mindset, particularly when that mentality is allowed to permeate their 8U, 10U, 12U and 14U structure. It rewards early-maturing players who may not have the long-term ceiling to be elite performers in their late teens and beyond (when it actually begins to matter). At the same time, late-developing players are excluded and cut, consequently leaving the sport or being segregated to a lesser training program that limits their development opportunities. These late developers may have huge long-term potential, but in this “peak-by-the-weekend” club, they are eliminated from the system before they’ve even had a chance to develop their potential. 

So what can hockey clubs do about it? Again, there’s no perfect answer. But a good start is being aware of the inherent bias, accounting for it when evaluating players, and maintaining a long-term development focus within a club, rather than chasing trophies. After all, the true prize should be developing every player within the club to their full long-term potential.

“If a club treats all kids the same and gives them equal opportunity, ice time and coaching, at the end of the day, that’s going to keep kids in the sport and continuing to develop,” said Martel. “And it will avoid a scenario where certain kids at a disadvantage.”

USA Hockey is educating its coaches on this subject.

“A youth coach being able to distinguish between power and strength advantages vs. a skill advantage is big. Sometimes the kid who is bigger and stronger and older looks pretty good, even though the weaker kid might have a better skill set,” Martel said. “Coaches should be spending more of their time at a young age looking for motivational edges than talent edges.”

Sorting itself out

Age differences tend to matter less as players get older. The relative age effect is most noticeable at younger ages and maybe again at 12U or 14U if the kids born early in the year happen to hit their growth spurt sooner than younger peers.

“The interesting thing is it all shakes out in the wash when everyone goes through puberty,” Martel added. “So it’s critical to keep kids involved in the sport as long as possible and not have them quit early because of what may have transpired. At a young age, it’s impossible to predict who is going to be a great player. The Sidney Crosbys of the world who are really good who turn out to be superstars, they’re an aberration. That’s not the norm. What’s a lot more common is the 10-year-old who didn’t look like much at age 10, but through patient coaching and a good development environment, turned out to be among the best players on the team the age 18.”

Change the cut-off date?

Martel said USA Hockey has considered its age categories and wondered “would we be better served with different breakdowns.” Some youth sports, he noted, put athletes into a new age class on their birthdays, in effect meaning they’re “the oldest and youngest in their group all in the same year.”

Regardless of the cut-off or breakdown, though, there is going to be some sort of relative age effect. Minnesota Hockey, for instance, uses July 1 as its birthday cut-off date for age groups to align more closely with its rich high school hockey tradition. But that just gives the kids with July and August birthdates an early edge – if coaches aren’t careful – over their May and June birthday peers.

The solution that spans all cut-off dates, Martel reiterates, is simple but fair.

“The biggest thing comes down to how clubs treat kids,” Martel says. “If they give them equal opportunities, then they all have a chance.”

More Newsletter Articles



Popular Articles

Now is the Time: A golden opportunity at 10U

09/26/2017, 2:00pm MDT
By Mike Doyle

ADM influencing change in youth football

09/28/2017, 2:00pm MDT
By Michael Rand

12U+: Simultaneous Regroup: A passing warmup

10/02/2017, 9:00am MDT
By USA Hockey

Tag(s): Newsletters