Often, the formula of success in sport presents it to us as the combination of talent, effort and, to a lesser extent, being in the right place at the right time, that is, luck. However, there is a factor that is rarely spoken and is often one of those that makes the difference between being successful or staying along the way. Although it seems surprising, we talk about the month of the year in which it is born. It was in the 80s when Roger Barnsley, a Canadian psychologist, began to realize that, in the main youth leagues and ice hockey professionals from his country, up to 72% of the players were born between the first and second quarter of the year (1). In fact, players born in January had almost 5 times more likely to play in the youth leagues than those born in December (1). Is it because those born in the first months of the year are more talented? Nothing of the sort. So? Basically, those born in the first months of the year have a level of maturation greater than those born at the end of the year, mainly due to the almost twelve months of difference in some cases.

The effect of relative age on sport 

This phenomenon is what Barnsley defined how the effect of relative age , and refers to the age difference between people who have been grouped together for a particular purpose or function (1,2). In the basic sport the categories are established by age groups, standing in most cases between January 1 and December 31 of each year. What is this fact? That compete with each other who, in some cases, will separate 12 months, with the difference at the physical, affective and maturational level that this supposes, especially in childhood and adolescence. In these circumstances, players born in the first and second quarter of the year (from January to June) are more likely to be identified as talented and, therefore, of being selected by higher level teams due to the probable advantages of growth and maturation they have about their companions born in the last months of the year (3–5). This circumstance seems to be especially critical between 15 and 18 years (6).

And although from Barnsley's first studies other works have appeared supporting the phenomenon of the effect of relative age in different sports such as football, basketball, handball or swimming (5.7–10), in other cases it seems not Give this effect. Thus, a recent study led by Dr. Jon Irazusta of the University of the Basque Country (Leioa, Spain) in more than 38,000 children between 9–14 years belonging to 37 sports found that, although the effect of relative age seems to be Obvious in the main male soccer leagues, basketball, handball and women's football, in the general analysis and in the rest of sports the date of birth was not a limitation to compete (11).  

But beyond the field of sport, can the phenomenon of relative age also have an academic or behavioral level? 

The effect of relative age beyond sport

As it could happen in the competition sport, it seems not the same to reach the world at one time or another of the year for school performance. Thus, being born in the first months of the year would explain some of the main differences in the notes obtained among children. For example, the psychologists Kelly Bedard and Elizabeth Dhuey observed that the youngest fourth grade students obtained scores in their grades between 4–12% lower than the oldest of the same course (12). That is, having been born only a few months later could mean obtaining a note up to 1.2 points less than those born at the beginning of the year. And although to a lesser extent, the differences were also observed in more advanced courses (8th grade), with a score between 2–9% smaller for the youngest. This circumstance, the authors say, will cause students born in the last months of the year to have less possibilities to access university studies (12).

Therefore, the month of birth can have some impact on academic results, with the smallest of the natural year dragging worse scores, which will have an impact on its future formation. Keep in mind that between a 5 -year -old boy born on January 7 and another born on December 26 of that year there is not only one year apart, but there is a lag of up to 20% of life . This results in, as a study from the University of Extremadura concludes, children born between November and December can have an 85% more likely to repeat a course than their classmates born in the months of January and February of the same year (13 ). The same authors indicate that the probability of repeating course is reduced to 20% in the case of students born between May and June with respect to those born in the first months of the year.

In the long term, as revealed by a complete report by the Institute for Prosecutor Studies of the United Kingdom, this will translate that children born in the last months of the year will have worse jobs and worse salaries that those born with the beginning of the year (14). These worst working conditions could explain that the youngest in their class have higher suicide mortality rates compared to their classmates a few months before and, therefore, relatively greater (15). On the other hand, in a study conducted by Australian researchers in more than 1,000 adults between 24–60 years, those who were born in the first months of the year demonstrated greater confidence in their abilities, as well as a greater willingness to assume risks in Life compared to those who had been the children of their class (16). This could in turn explain that the elderly of the course seem more predisposed to occupy leadership positions in the future. It is what seems to happen in the case of the main American politicians (17). Therefore, the month of birth could influence the construction of our personality and, therefore, of our professional future.

Conclusions

The fact of being born in January, August or December, but there is more and more evidence that the date of birth can determine the chances of success. And since we do not have the opportunity to select our date of birth, it would be desirable for the education system to provide some mechanisms to correct these inequalities. For example, tests could be carried out to know the cognitive and affective maturity of the children and, before being forced to enroll all the children born during that natural year regardless of the month of birth, proceed to not enroll until the course following those in which some deficit is detected. Another possible solution could be oriented towards the promotion of evaluation programs that normalize the results by ages (or month of birth), so that all students were compared to those of the same relative age. This option would eliminate the lottery from being born in one month or another, being really important since, as we have seen, you can determine the career and the future work. No one is to blame for being born in one month or another.  

References:

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2. Thompson Ah, Barnsley Rh, Stebelsky G. “Born to Play Ball” The Relative Age Effect and Major League Baseball. Sociol Sport J. 2016; 8 (2): 146–51. 

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