One question reveals: Are you a narcissist?

If you are a narcissist, you probably think this story is about you, and you are correct (as you so often are – right?).

That kind of thinking makes it quite easy for researchers to identify the most self-involved among us: They just ask people if they are narcissists. The real narcissists speak right up, a new study shows.

"People who are not narcissists would never say that they are," because of the negative traits – such as vanity and selfishness – associated with the word, says Sara Konrath, a researcher at Indiana University in Indianapolis and, until recently, the University of Michigan-Ann Arbor. "Somebody who is a narcissist doesn't think it's all that bad and is maybe even a little proud of it."

Konrath is lead author of the study, published Tuesday in the journal PLOS ONE. She and colleagues at Ohio State University and Gettysburg College developed the one-question test for narcissism in trials involving 2,250 people.

The question: "'To what extent do you agree with this statement: 'I am a narcissist?' " Subjects were told the word means "egotistical, self-focused and vain." Those who heartily agreed, choosing 6 or 7 on a 7-point scale, were the same people who scored high for narcissism on a traditional 40-item questionnaire. The self-proclaimed narcissists made up about 5% of test-takers.

Though the finding is mostly of interest to time-pressed psychology researchers — who still will get more information from longer questionnaires — it does give some insight into a condition that causes problems for individuals and society. Narcissists are low on empathy, have difficulty with relationships and tend to get angry and defensive when criticized, the researchers say.

In its most severe form, narcissism is considered a psychological disorder. In milder forms, it's a personality trait that may come with some positive aspects, such as creativity, happiness and high self-esteem – though the breed of narcissist identified through the one-question test did not score particularly high or low on self-esteem.

In general, "narcissistic people do think there is value in it," Konrath says. "They are being assertive and strong and getting what they want."

The term narcissism comes from the mythical Greek character Narcissus, who fell in love with his own image reflected in the water.

The fact that narcissists are willing to own that label is not surprising, says clinical psychologist Joseph Burgo of Chapel Hill, N.C. "I think a big part of it is that we live in a culture that encourages narcissism … it doesn't view bragging as a bad thing. We live in a culture of self-display."

Burgo, an author whose next book, due in 2015, is called The Narcissist You Know, says many narcissists are outwardly confident and charming and "able to accomplish great things because they believe they can."

On the inside, narcissists are full of shame and their bravado is a defense, he says: "It's not real."