Birth Order Doesn't Dictate Your IQ Or Personality Traits, Says Study, So I Guess Should We Stop Gloating Over Our Siblings

There have been a lot of studies over the years suggesting that eldest children are smarter and have different personality traits than their younger siblings — but if you are an older sibling, you might have to stop lording it over the younger kids now. A new study says that birth order doesn't really mean anything for IQ or personality. As an oldest sibling, I can tell you that I am crushed. How am I going to keep my little sister in her place now?

The study, which involved over 300 high school students, found that there are differences in IQ and personality between older and younger siblings; older siblings, for example, are typically more outgoing and have higher IQs. However, the study also found that the differences were so small they were basically meaningless.

"[In] terms of personality traits and how you rate them, a 0.02 correlation doesn't get you anything of note," Brent Roberts, a psychology professor at University of Illinois and one of the lead researchers on the study, explained to Science Daily. "You are not going to be able to see it with the naked eye. You're not going to be able to sit two people down next to each other and see the differences between them. It's not noticeable by anybody."

Essentially the trend has statistical significance, but no significance whatsoever for comparing people in any sort of practical sense.

I feel so betrayed.


Of course, older siblings can always try to console ourselves by saying that it's possible this study got it wrong... but unfortunately, I think we might be out of luck there. The study offered the largest sample size of any study that has been done on this subject to date, and it controlled for factors such as a family's economic status, the number of children, and the relative age of the siblings. As such, its findings are probably pretty reliable.

But hey, anything is possible, right? At least until it's replicated by another study and produces the same results. (We're waiting, science.)

Still, as Rodica Damian, one of the other lead researchers, explained, “The message of this study is that birth order probably should not influence your parenting, because it's not meaningfully related to your kid's personality or IQ," Damian said.

Now, as for whether or not that means we're going to start treating our younger siblings better? Let's just say that remains to be seen.

Image: Giphy