Older siblings have higher IQs… but only just

Huge study suggests first-borns are that little bit smarter

Siobhan Fenton
Monday 20 July 2015 12:31 BST

Sibling rivalry can be a scourge for many families.

But now new research has poured fuel on the fire by revealing that older siblings have higher IQs.

However, whilst first-borns are technically smarter - they aren’t ahead by much. The study found that whilst older siblings have higher IQs, it is only by one IQ point.

The research by academics at the University of Illinois studied 377,000 high school students to analyse how family chronology affects peoples’ lives.

The results were published in the Journal of Research in Personality.

The study also revealed that first-borns tend to be more outgoing, agreeable and conscientious. They are also less likely to experience anxiety than their younger siblings.

The university say that the study is “the biggest in history looking at birth order and personality.”

However, for anyone jealous that an older sibling might have an unfair advantage in life, they are quick to reassure that the finding is so small as to make little or no impact on families.

Professor Brent Roberts and Rodica Damian who led the research, said that “the difference is statistically significant but meaningless” and that the one IQ point would “have no practical relevance to people’s lives.”

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