Nearly a third of teenage girls have met people offline after becoming online friends, according to a new study. In many cases the identity of that online character was not fully confirmed before the teens set up a real-life meet-up.

In addition, one in 10 experienced some form of exploitation — ranging from creepy sexual advances to rape — during that offline interaction.

The study, published today (Jan. 14) in the journal Pediatrics, looked at teenage girls, half of whom had been abused in some way in real life. Those who faced abuse or neglect were likelier to exhibit "high risk" online behavior, such as having racy social media profiles or accepting online sexual advances. Risky online behavior, in turn, was tied to meeting Internet "friends" offline.

But because the study included a large number of at-risk youth, some experts doubt those numbers apply to the general population.

Teenagers may first meet a friend-of-a-friend online and meet face-to-face later, but complete strangers are a different story, said Parry Aftab, an Internet privacy lawyer who runs WiredSafety.org. [Adolescent Angst: 10 Facts About the Teen Brain]

"Straight strangers? No way. I just don't see that as happening. The kids have gotten very sophisticated about this issue," Aftab said.

Janis Wolak, a senior researcher at the Crimes against Children Research Center, agrees. In general population surveys, Wolak has found that very few teens meet online strangers in person. And from that subset, so few are sexually assaulted that scientists can't draw meaningful statistics, she said.

Mostly harmless

Since the days of AOL chat rooms, parents have worried about predators luring teens into dangerous offline meetings.

Though it can happen, the rise of the Internet has coincided with a steep drop in child sexual abuse, suggesting that online exploitation isn't a huge problem, Wolak told LiveScience.

Still, survivors of abuse can have trouble setting boundaries or detecting predatory or inappropriate behavior, Wolak said. That could spill over into online interactions, she said.

Vulnerable teens

Jennie Noll, a psychology professor at Cincinnati Children's Hospital, had been studying abused teens when she began noticing their online profiles were markedly different.

"They would, more often than some other kids, post racy photos of themselves or sexual utterances," Noll told LiveScience.

To test that observation, she and her colleagues studied 130 girls ages 14 to 17 who had seen Child Protective Services for sexual and physical abuse and neglect, as well as 125 demographically similar teenagers with no abuse history. The girls answered questions about online behavior. A year later, Noll asked how many of the girls had met an Internet friend offline.

Thirty percent of girls (both abused and not) reported an in-person encounter with someone they first met online. About 10 percent of the girls experienced something negative — often creepy sexual overtures or intimidation during that meet-up. Only one prosecuted rape occurred as a result of the offline meetings, Noll said.

Consistent with her anecdotal experience, abused teens were likelier than non-abused teens to have racy social media profiles or report fielding sexual advances from strangers — behaviors that were separately tied to meeting strangers offline.

Mitigating risk

While the findings are disturbing, the team also found that high-quality parental relationships and open communication could reduce the risk that teens would meet online friends in the real world. Past research has found parents are in the dark about what their teenagers are doing online, with 70 percent of teens hiding some of their online behavior from parents, including accessing porn or violent content online and pirating music or movies online.

In the new research, the scientists found that Internet blocking software didn't affect real-life risky behavior.

Still, it's important for parents not to worry too much about online predators, as the most likely abusers are relatives, family friends, or acquaintances of children known in real life, Wolak said.

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