They found that 54 percent of the profiles contained information on risky behaviors, with 24 percent referencing sexual behaviors, 41 percent referring to substance abuse and 14 percent posting violent information.
Factors associated with a decreased risk of posting risky behaviors included displaying religious involvement or involvement with sports or hobbies.
For the second study, the researchers randomly selected 190 profiles of people between 18 and 20 who displayed risky behaviors, such as sexual information. Half were sent an e-mail from a physician that pointed out that the physician had noticed risky behavior on their profile and suggested changing the displayed information. The e-mail message also provided information on where to be tested for sexually transmitted diseases.
Almost 14 percent of those who got the e-mail deleted references to sexual behavior, compared with 5 percent of the others.
"This was a creative and unique way to reach kids," said Kimberly Mitchell, the author of an accompanying editorial in the same issue of the journal and a research professor at the Crimes Against Children Research Center at the University of New Hampshire in Durham.
Mitchell advised parents not to try to forbid their children from using these sites altogether. "It's important for parents to understand how important these social networking sites are to kids," she said. "They're here to stay, and they're not all evil. There can be some really positive aspects to these sites. But adolescents aren't necessarily thinking 10 years ahead, when employers or college administrators may look at these sites. Teens live in the here and now, so parents need to talk to kids about the longer-term impacts and help them think through some of the repercussions."
Moreno suggested that parents ask teens to show
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