Tag Archives: validity

The validity of online IQ tests

Boris Johnson’s recent comments have gotten everyone talking about their IQ. There are numerous tests to measure IQ, many of which are available online and used often. But are they scientifically valid?

One of the more interesting fall-outs from Boris Johnson’s recent speech is that he’s got people talking about intelligence and IQ a lot. This is likely a good thing. Intelligence is a tricky subject, so the more public discussion there is about it the better, in terms of keeping people informed. Because it’s not unusual to encounter someone who will mention having a high IQ without specifying why they think this is and what it actually means.

There are numerous IQ tests used by psychologists, such as the Stanford-Binet test, the Weschler Adult intelligence scale and so on. These are typically thorough tests designed to assess various different abilities via different types of tasks. They are regularly revised and updated, and typically have to be administered by a trained professional in specific conditions. They can also cost a fair bit, as they are actually scientific tools, like microscopes and the like.

Most non-science types outside the field of intelligence research won’t have access to these official tests though, so will have to look elsewhere. The obvious place to look is online, and sure enough if you type “IQ Test” into Google you get a lot of hits. There are countless free IQ tests online, and odds are someone bragging about their IQ got their score from one of these. But are they a valid, legitimate way of assessing your IQ?

Now I’ve taken on a lot of IQ tests over the years as it was somewhat of an interest of mine, what with coming from an underprivileged background in comparison to peers around me. I’ve done considerable tests of late and had a range of different scores. One particular test gave me an estimated IQ of 142. This score would suggest that I’m a genius. According to the normal distribution, that score puts me in the top 2% of the country. Not bad at 21 years of age I’d say.

I then did a similar IQ test on a different website. On this occasion, I got a score of 123. This puts me in the top 9% of the country, which still sounds pretty impressive. But there’s a problem. How can I be losing 19 points in an IQ test one after the other on two different websites? Something doesn’t seem right.

So I tried one last website just to see if I get a score somewhere in the middle. This website was slightly different though. It claimed that it provided ‘advanced feedback’, which is basically a glorified way of saying it tells you how many you got right, instead of merely giving you the IQ score like the two previous websites did. Well I did the test, and it returned a score of 139, which gave me a nice sense of relief that I’m back in the top 2% of the country again.

Ok so I’m going to explain what is wrong with all this. Firstly the range of IQ’s doing the same thing is quite a lot, which raises questions over the accuracy and hence validity of these tests. The next issue is the type of these questions. On all three of these websites, all the questions were multiple choice. You could basically guess the right answers, inflating your scores (albeit the odds of being correct is 1 in however many options there are per question). I am not a fan of multiple choice questions, mostly because I answer those quickly. Now it’s time to reveal what the advanced feedback came back with;

You got 5 questions right out of 15 in a time of 6 minutes. You received a bonus for finishing quickly. We estimate your IQ to be 139.

Basically what this said is I got 33.3% of the questions right (not great by my exacting standards), but my score was higher because I finished at a rapid rate of knots. So pace is reflecting on my scores. Is getting an answer wrong but answering it quickly really what defines our IQ? Is this what we should be teaching our children? No.

What does this mean for online IQ tests? Well it suggests they are not IQ tests at all, just some sort of web gimmick that obtains web traffic and people’s custom. The websites I used had adverts all over them, which is clearly how they are funded, and I doubt they would want to call you stupid otherwise you wouldn’t return to them.

Here’s my advice: There may well be valid online IQ tests, but tread carefully if you’re using them. And be wary of anyone who publicly shows off about their scores on such tests. An intelligent person would do no such thing, unless they are arrogant and conceited in which case you wouldn’t want to approach them …