My husband is a champ when it comes to building things. Over the years, he has built dressers, doll houses, our kitchen table, and even our house. But the few times I've come home with an assemble-it-yourself bathroom cabinet or computer desk, he has looked at all of the pieces and parts like they were amorphous objects from another planet. And he has exactly zero interest in reading the directions. So it came as no surprise to me to hear that in 2008, Petra Hesser – who, at the time, was the head of the German division of DIY-assembly furniture maker IKEA — made headlines by claiming that women are better than men at assembling flat-pack furniture, simply because women take time to sort out the materials and read the directions.

"Men never look at the instruction leaflet and have the most problems when assembling our furniture because they think they can do it without help," Hesser told a German news agency in 2008. "A woman will neatly lay out all the screws while a man will throw them in a pile," Hesser added. "Something always goes missing."

But for a group of researchers at Norway's UiT The Arctic University of Norway, Hesser's theory cried out to be tested. In 2015, the research team gathered 40 university-aged men and women who claimed to have similar levels of experience assembling furniture. The participants were asked to assemble IKEA's "Udden" kitchen trolley as quickly and accurately as possible. Half of the participants were given a copy of the assembly instructions while the other half were simply given a photo of what the finished product should look like. In addition to evaluating the participants for the time and accuracy of their assembly, researchers also scored participants on their mental rotation skills (their ability to mentally move objects and shapes around to make various pieces fit.)

IKEA's Udden Kitchen Trolley IKEA's Udden Kitchen Trolley was the object of mass assembly for this experiment. (Photo: IKEA)

There was only thing wrong with that theory ...

The results? Hesser's theory was sadly debunked. Researchers found the men were faster and more accurate in their trolley assembly than the women. It took the men an average of 22.48 minutes to complete the assembly with instructions and 24.80 mins when they were only shown a photo of the trolley. For the women, the average completion times were 23.65 minutes with instructions and 28.44 minutes without.

Interestingly, Hesser's claim that women read and benefited from instructions was true. In fact, when women were given the instructions, their assembly times were faster than the men who didn't receive instructions. The amount of time it took them to complete the project also improved drastically — by 4.5 minutes — when they were allowed to use the instructions, whereas the time for the men stayed relatively the same with or without instructions.

As for accuracy, men averaged a score of 8.9 (on a scale of 1 to 10, with 10 being perfect construction) with instructions and 7.6 without. The women had an average score of 7.5 with instructions and 5.7 without.

So how about those mental rotation skills? Men outperformed women here, too. But one thing the researchers noticed was that participants, both male and female, who scored poorly on their mental rotation skills tended to spend more time reading the directions. When they adjusted their data to factor out mental rotational skills, they found there was virtually no difference between the genders in the time it took to assemble the trolley. It's possible that the reason men were able to assemble the trolleys more quickly and accurately than their female peers was because they were less reliant on the printed instructions to do the job.

Of course, this small study is hardly the final word on whether men or women are better at assembling furniture. But one takeaway the study did prove was that male or female, instructions help. So the next time this situation arises at your house, take a look at them. And for the sake of a sound marriage, sort out those pieces so nothing gets lost!