A new study has found that you really do have to be “the best of the best” to succeed in the business world. An examination of the backgrounds of Fortune 500 CEOs from 1996 to 2014 has found that around 40 percent attended a top university and had better cognitive abilities than the overwhelming majority of the general population.

Recently, Jonathan Wai from Duke University and Heiner Rindermann from Chemnitz University of Technology in Germany used information available in the Fortune database to investigate the educational background of hundreds of Fortune 500 CEOs over a 19-year time period. According to the study, where individuals received their higher education is a good indication of their cognitive abilities, since those who graduate from these elite schools generally tend to be at the top percentile of intelligence for their age group.

However, not all CEOs were educated in U.S. universities, and different countries use different methods to measure an institution’s ranking, so to overcome this obstacle the team used the QS World University Rankings (2012), an international university comparison ranking, to determine elite school status within each country. In general, each country was allowed a maximum of 10 schools, but some countries had fewer than this amount.

The researchers observed that the number of Fortune 500 CEOs who had received an education at an elite institution was between 37 and 41 times higher than the rate in the general population. In addition, the low numbers who reported not having attended college indicates that “contrary to media stories glamorizing college dropouts and/or CEOs who went to relatively unknown colleges,” nearly every Fortune 500 CEO graduated from college, and most also went to an elite school, the report read.

“This suggests that Fortune 500 CEOs (a quite select group of CEOs) are very smart compared to the general population, probably in the top few percentiles of intelligence,” Wai wrote to Medical Daily in an email.

Although there seems to be a clear link between CEOs and elite education, it’s not clear whether it was the individual's natural intellect, the education they received at the elite institution, or their “access to elite networks” which enabled them to rise to the top of the business world. The researchers reasoned it was most probably a combination of all three.

"All our abilities are developed over time, but it would be fair to say that all experts are 'born, then made,' which is to say that we aren't blank slates to begin with," wrote Wai, explaining that although CEOs did work hard to get to where they are, but they also have much higher rates of elite education than the general population. "At the same time," added Wai, "at least relative to the general population, Fortune 500 CEOs have high intelligence."

Source: Wai J, Rindermann H. The path and performance of a company leader: A historical examination of the education and cognitive ability of Fortune 500 CEOs. Intelligence. 2015.