Wednesday, 13 August 2014

The relation between IQ and job success

As consultants in the area of online assessment we work a lot with intelligence tests. We know that they are excellent predictors of job performance. However, when talking to clients we are often faced with scepticism. Do they predict anything beyond first year grades in university? Do they predict “real life outcomes” such as job success?

Apparently Nathan Kuncel, psychology professor at the University of Minnesota, was faced with the same questions. In a TED Talk, he takes us through a huge body of research on the predictive power of intelligence tests. And besides you will also learn what this has to do with Captain Janeway from Star Trek.

Thus, the data of over 3,000 studies and over 600,000 individuals show that the tests predicted success at university – degree completion and grades at various exams, but also faculty ratings, citation count, and research productivity. This is maybe not too surprising for even the sceptics. However, they also predicted other outcomes such as job performance, creativity, or career potential. The relationship between test results and success is highest for performance on complex jobs and training success, but also considerable for performance on jobs of medium to low complexity, leadership performance, and creative performance.

What might seem surprising is that IQ test scores also predict creativity and leadership performance. However, when looking a bit more closely, it all makes perfect sense. Creativity is not just about creating ideas, but also about interconnecting them and knowing which of them are best. For the latter, intelligence is needed. Similarly, leadership is not only about interacting with people, but also about setting goals and organising work. Again, for this, a certain level of intelligence is required. Nathan Kuncel and his team also looked at whether there a point beyond which test scores don’t matter and found that, on the contrary, the relationship becomes stronger at the extremes. IQ scores at age 13 were predictive of doctorates, scientific and literary publications, patents, and income. And this was the case even after controlling for social class.

Now, of course intelligence is not the only predictor of success. We know that there are other factors such as motivation, self-discipline, or even the mind-set. We also know that being smart does not prevent you from doing very stupid things. But still, intelligence is a powerful predictor of job success, as loads and loads of data and analyses show. Therefore it makes a lot of sense to use intelligence tests in employment testing.


  1. It would be interesting to find out the IQ of some of the people I work with as well as those I've hired. It does make sense to conduct intelligence test in employment testing. It might prevent a lot of frustration down the road.

  2. Thank you for this comment. In fact it makes a lot of sense to conduct intelligence tests in employment testing because it prevents frustration on both sides: for the employer as well as for the applicant. Nobody benefits from someone working on a job they do not have the abilities for, neither the employer nor the employee.