New research from Ohio State University suggests narcissists know what they are -- and are able to readily admit their vanity when asked.

When researchers staged a series of 11 experiments that involved more than 2,200 people of all ages, they found it was possible to identify those who had narcissistic tendencies by posing the following question:

"To what extent do you agree with this statement: 'I am a narcissist.' (Note: The word 'narcissist' means egotistical, self-focused, and vain.)"

Participants rated themselves on a scale of 1, which implied "not very true of me," to 7, meaning "very true of me."

Results from the study, which appear in the journal PLOS ONE, showed that participants' answers to the one question lined up quite closely with several other validated measures of narcissism, including the widely used 40-question Narcissistic Personality Inventory.

"People who are willing to admit they are more narcissistic than others probably actually are more narcissistic," Brad Bushman, co-author of the study and a professor of communication and psychology at Ohio State University, said in a news release. "People who are narcissists are almost proud of the fact. You can ask them directly because they don't see narcissism as a negative quality -- they believe they are superior to other people and are fine with saying that publicly."

Bushman conducted the study with Sara Konrath of the Indiana University Lilly Family School of Philanthropy and Brian Meier of Gettysburg College.

Konrath said understanding narcissism has many implications for society that extend beyond the impact on the individual narcissist's life.

For example, "narcissistic people have low empathy, and empathy is one key motivator of philanthropic behavior such as donating money or time to organizations," Konrath said.

As well, narcissism is problematic "for both individuals and society. Those who think they are already great don't try to improve themselves," Bushman said adding that, ultimately, "narcissism is bad for society because people who are only thinking of themselves and their own interests are less helpful to others."