Researchers identified one simple question that can reveal who is a narcissist and who is not.

The Ohio State University research team found they could identify narcissistic people by simply asking them how narcissistic they were (take the test here). Participants were asked to rate their own personal narcissism on a scale of one to seven.

The team conducted 11 experiments encompassing over 2,200 people of all ages. They found people's answer to this question tended to line up closely with other narcissism measuring techniques such as the Narcissistic Personality Inventory. The new survey, dubbed the Single Item Narcissism Scale (SINS), could do the same job as the over 40 question test in just one.

"People who are willing to admit they are more narcissistic than others probably actually are more narcissistic," said Brad Bushman, co-author of the study and a professor of communication and psychology at The Ohio State University.

Narcissistic people tend to not see it as a negative quality, and therefore are more likely to admit to it. Understanding narcissism could have implications for society that are bigger than the individual person.

"For example, narcissistic people have low empathy, and empathy is one key motivator of philanthropic behavior such as donating money or time to organizations," Bushman said. "Overall, narcissism is problematic for both individuals and society. Those who think they are already great don't try to improve themselves." 

People who scored higher on the narcissism scale tended to report less agreeableness, and more "anger, shame, guilt, and fear." These individuals also experienced negative interpersonal outcomes, such as exhibiting antisocial behavior when their ego was threatened.

The advantage of this new test is it allows researchers to identify narcissistic individuals quickly and easily.

"We don't think SINS is a replacement for other narcissism inventories in all situations, but it has a time and place," Bushman. 

The findings were published in the journal PLOS ONE.