David vs Goliath: On the complexity of talent identification
Thanks to Ziyaad Parker, one of the authors of the full text reference, for this article. Follow Ziyaad on twitter: @ZiyaadParker7 
These two players (left and right) are opposing captains of their respective under-14 (i.e. 13 year old) rugby teams in Cape Town, South Africa. For reference, the referee (middle) is of average height ( about 6 ft.).
Attempting to identify a future Goliath is hampered by this stat: only 31% of players selected at U13 Craven Week appear at the U18 Craven Week a few years later 1.
That’s correct, talented young players do not necessarily become talented older players – in fact, more often than not, they don’t: the majority of players selected for the U13 Craven Week do not go on to be selected at subsequent U16 Grant Khomo and U18 Craven Week. There are two theories which try to explain these findings i.e. the attributes that determine success at U13 level are different to those that determine success at U16 and U18 level; or the player has characteristics associated with success in rugby but those characteristics change over time. Growth and maturation occur between the age groups in question (13-18 years). As each individual is not the same as the next, this process occurs at different rates resulting in some 13 year olds being taller and heavier than other 13 year olds (See picture). However, by the time both players reach 17 years old the advantage that an early-maturer had over a late-maturer, in terms of size, may have diminished thus resulting in an even playing field for both players in that regard.
Talent identification is a complex process especially in a sport like rugby in which size is related to performance. Therefore, predicting future success from participation in junior tournaments such as U13 Craven Week may not be accurate as so few players convert U13 success to success at U18 level.
Reference (full text freely available)
1. Durandt, J., Parker, Z., Masimla, H., and Lambert, M. Rugby-playing history at the national U13 level and subsequent participation at the national U16 and U18 rugby tournaments. South African Journal of Sports Medicine 2011;23(4)
Rugby Science 
Most sports leagues, regardless of what sport, sort players by age. But that picture clearly shows the huge size disparity between two players that are the same age. The bigger kid has a natural advantage, at least for a while. So should leagues be organized by size then? Or talent? It’s hard to find a way to make the playing field as even as possible.
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Thanks for the comment Jodi…The “play by weight” suggestion is also contentious: you can have a very overweight 14 year old prop who weighs 140kg…which would have him scrumming against leaner u19 props…the u14 player’s spine is simply not well developed enough to handle this!
I agree there is no simple answer to this: between the ages of 14 to 18 years, boys can be 4 years apart biologically! So grouping them biologically would be ideal, but there is not practical way to do this! Its a tough one!
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Maybe we should stop looking at the players and take a step back and ask ourselves where are the coaches that should coach these players to become better rugby players!
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Great comment! There is a belief in SA that if you PLAYED rugby, then you can COACH rugby. This is illustrated by the fact that 80% of the active coaches who attend BokSmart courses have NO coaching qualification whatsoever…
While being a former player certainly gives you a good base as a coach, it does not determine whether you are a good coach or not…
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To become a coach requires no education in this country. That is a very big problem. Coaching rugby game-plans and the related structures is the order of the day – Programming! They keep coaching the easy stuff! Where are rugby players coached to become better at the actual position they play? To feed their game sense? to enhance their skill, decision making, anticipation? It is locally published that in NZ the small sided games that are coached/implemented with young kids are focused around skill development and the avoidance of contact – isn’t the game of rugby designed around avoiding contact? and to score tries? There once lived a legend that said “phases of play are unsuccessful attempts at scoring the try in the first place!”
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When I was Director of Coaching for WP in the 80’s I tried very hard to get rid of the U-13 Cravenweek. As you know it’s still there and they have also introduced the Grant Khomo U-16. These provincial age group tournaments should not be part of rugby development. the biggest, heaviest and strong players are being selected and not the most skilful. SARU now also have Elite groups at U-16 level. I do not understand why time, effort and money is spent on an elite group at this stage of their development. These boys must just play rugby during this time, develop their individual skills and enjoy the game.
Alan Zondagh
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Agreed! Thanks for the comment, Alan.
This is without mentioning the fact that those who DO go to Craven Week under-13 are under enormous pressure – this pressure results in abnormally high and more severe injuries than normally occur at this age group…the scary thing is that it often the parents of the player who comprise his health!
Strangely, this tournament seems to be marred by more incidences of parents trying to get their child to play a match while still injured than the other craven week tournaments.
As long as this till happens, this tournament is more of a hazard than a help to players!
This being said, the other side of the coin is that the tournament is good for getting spotted for a scholarship for a big rugby school. But as this article indicates quite clearly, those who are at craven week u-13 will probably not be playing at that same level by under-18!
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The article concludes that seventy-six per cent of the players selected for the U13 tournament (2005) did not play at the U18 national Craven week tournament (2010). This is attributed to two reasons with one being given greater credence; that is, maturation rates changing player characteristics. Personally, I’d consider a 24% conversion from U13-U18 to be evidence of successful talent retention within the sport given that the socialisation effects of sports for these age groups are far from set with huge attrition to other sports (sampling), continuing to play within the sport but at the recreational level, change in motivational or reward system of the player, wide ranging contextual factors from coaching style, family influences, moving house/school, accidents, etc or as the article suggests a failure to exhibit mastery at the required level. When looked at in a vacuum you could argue that the competition is failing to ‘develop’ (look after) the pool of identified players but in the context of competing with other sports and non-sporting interests (distractions) then to retain 24 players at 17 years of age from a starting resource of 100 players aged 13 years I think is good. Especially, if the quality gap between the 2 comps (U13 vs U18) is significant ! Quality players need the opportunities to play against quality players in order to develop.
on another point raised …as for injury nz/aus does a combination age/weight category and a 2010 boksmart report appears to advocate it
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Thanks for the comment, Craig and some fantastic points made here. I would agree with you that a 24% conversion rate is not bad – especially from a talent id perspective. Also, I would add that this is probably indicative of a good system.
However one of the thrusts of the blog post, which we hoped to illustrate with the accompanying photo, was aimed at isolated schools more than the system as a whole. If school X scouts and “purchases” (this term is used very loosely to indicate a form of scholarship or incentivised schooling for a child) a craven week under-13 player, there is 76% chance this player will not be the same player, relatively, in Matric. In fact, as you point out, the player may not even be playing rugby anymore. Although a comparable study has not been performed in South African cricket, I would hazard a guess that you would have more chance of making a correct scouting in cricket, than rugby – assuming under-18 is your focus, of course.
As for the age/weight comment – I am not sure I understand you 100%. As far as I am aware, Aus and NZ, despite trialling weight categories for a couple of years, have returned to age categories for rugby union? Am I mistaken? I am an author on that BokSmart 2010 report you refer to and the point was not to advocate weight categories, but rather to try and limit huge weight discrepancies WITHIN age categories of two years (hence the age-banding legislation). This is easier said than done, and so the age-banding was felt to be a step in the correct direction, at least. I would be interested to hear your opinion on this further and on the current Aus/NZ policies on this?
Thanks again for the comment!
James
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it was reported In “Die Burger” this week a boy in SWD team was 116 kg and South African Springbok Captain was 110 kg. it is a disgrace it let your son be over weight and embarrassing to South Africa.. the school must leave by example in the 21 century. over weight is not expectable cheers LOVES RUGBY
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