While it is often thought that only childs are narcissistic, research finds that they are no more so than children with siblings. (Shutterstock/Doreen Salcher)
New German research has found that the popular stereotype that only children are more narcissistic than children with siblings may not actually be true.
Carried out by researchers at the University of Leipzig and University of Münster, the new study looked at 556 adults with an average age of 46.3 years.
The participants, who were a mix of only children and those with siblings, completed an online survey that asked them if they believed that only children are more narcissistic than people with brothers or sisters.
This was in order for the researchers to test the prevalence of this stereotype.
The researchers focused on two key aspects of narcissism: people feeling grandiose about themselves and being more prone to rivalry.
The findings, published in the journal Social Psychological and Personality Science, showed that both only children and those with siblings shared the same view that only children are more narcissistic in both aspects than those with brothers and sisters.
To then test the accuracy of the stereotype, the researchers analysed data from 1,810 people – again a mix of only children and those with siblings – to measure their narcissism levels.
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They found that the scores of narcissistic traits for only children were not that different from those with siblings, and the findings also held true even after taking into account possible influencing factors.
“Some of the past research has reported no difference between only children and non-only children in terms of narcissism and some of the past research has reported such a difference,” said study author Michael Dufner.
“We can now say with rather high confidence that only children are not substantially more narcissistic than people with siblings.”
The researchers add that while many think that increased levels of narcissism among only children is a reason for having more than one child, this may not now be a valid argument.
“When sociologists, economists or policymakers discuss the downsides of low fertility rates, they should let go of the idea that growing up without siblings leads to increased narcissism,” said Dufner and his teammates.
“There might, of course, be economic or societal costs associated with low birth rates, but increasing narcissism in the upcoming generation does not seem to be a factor that is relevant to the discussion.”