30 Apr 2016

IQ tests: what can they tell us?

From This Way Up, 12:30 pm on 30 April 2016

An IQ test measures your intelligence – but what else can it say about an individual?

Puzzle pieces

Photo: Flickr user Ken Teegardin / CC BY-SA 2.0

"Perhaps the most arresting finding is that IQ scores taken in childhood are predictive of mortality. Smarter people live longer, and this association is still there after controlling for social class" - Stuart Ritchie.

There is evidence linking higher IQ scores with better school performance, career success, a higher income, living for longer and having better physical and mental health.

That's where things start getting complicated because  – as scientists like reminding us – correlation does not equal causation. So could a high IQ score just be a handy indicator or proxy for things like better childhood nutrition, your upbringing and your relative wealth?

Stuart Ritchie is a postdoctoral fellow in cognitive ageing at the University of Edinburgh who calls IQ tests "...some of the most reliable and valid instruments in all of psychological science".

He's working with a treasure trove of old Scottish records that are providing some great insights into how well people age, and how IQ can be used as a health predictor for later life.

"We need IQ tests to help us understand how the brain ages, and how we can help it age more healthily. We need IQ tests to help us work out how to boost people's intelligence, and thus to boost their productivity. Perhaps, above all, IQ tests are one of the tools with which psychologists can dissect and examine human intelligence: we'd be extremely unwise to continue to ignore their insights" - Stuart Ritchie.