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?

In the spirit of scientific investigation, I tried a few. They’re easy enough to do; you just need an internet connection and maybe a Facebook or Twitter account to “log in” with. My findings are discussed below.

Test 1

Test 1. Photograph: Dean Burnett

Based on this first test, I’m clearly a genius. This shouldn’t really be surprising, I have PhD in neuroscience, am a university lecturer and tutor and a Guardian science writer, how could I not have a vastly superior intelligence? According to the normal IQ distribution, an IQ of 133 means I’m in the “very superior” category. Only 2% of the population have an equivalent or higher IQ. According to this, Boris Johnson thinks I should be getting more support, which is nice.

This is a scientific investigation though, and a single data point is not enough to base conclusions on, so further tests are required.

Test 2

Test 2. Photograph: Dean Burnett

Obviously, I got overly complacent, even arrogant, after scoring so highly on the first test, and my performance suffered. Based on the second test, I’m 10 IQ points less intelligent than when I did the first test. According to the normal distribution, this knocks be down a category into the “superior” group, along with 7% of the population. It’s still quite respectable, but for someone as clearly brilliant as me, it’s an indignity and it will not stand!

Test 3

Test 3. Photograph: Dean Burnett

For the third test, I really focused, in order to claw back some self-respect and boost my IQ score. It appears I overshot somewhat though, as my final score was “over 140”. Let’s think about that for a moment: I scored so highly that the software itself gave up trying to work out my IQ after it exceeded 140. It also tells me I am “one” intelligent person. I find that “one” to be vaguely accusatory, as if it doubts whether a single person could score so highly. But I did, because I am clearly a Hercules of cognitive ability. If you think this is an exaggeration, count the exclamation marks!!

Test 4

Test 4. Photograph: Dean Burnett

This test claimed to be “advanced” so I thought I’d best give it a go. I’ve clearly exhausted the standard IQ tests meant for the proles, so obviously I need something more challenging. But, I still scored 138, keeping me comfortably in the “very superior” category. Even the advanced test can’t hold back my intellectual prowess. It seems I’m one doomsday device away from conquering the world.

Conclusions

At this point it would probably be informative to reveal my techniques for getting such high scores. Basically, all the tests used multiple choice questions, and I answered each one entirely at random. The whole thing took me less than half an hour. While it is technically possible that I regularly chose the correct answers due to chance alone (one issue with using MCQs in IQ tests), the odds against this are incredibly high. The results provided by one test give us something of a clue as to what’s going on

Some "questionable" results. Photograph: Dean Burnett

So I got barely 30% of the questions right, but because I did it quickly I have a huge IQ score? This (advanced) test suggests that a sign of intelligence is doing something wrong but fast, and rewards you for this. I can’t think of any other scenario where that would happen. If a plumber told you “I destroyed your boiler as soon as I touched it”, paying him a bonus would not be the first thing that came to mind.

This cursory investigation suggests that many online IQ tests aren’t what they claim to be, but are just gimmicks to obtain web traffic and people’s custom. The ones I used were strewn with ads, and I can’t imagine something intended to sell products would risk calling customers stupid (not until they have their money, at least).

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.

Dean Burnett reveals signs of his failing intellect via Twitter, @garwboy