(A MySpace spokeswoman, Tracy Akelrud, said the site used other controls to detect under-age users. "If you are under 17, you will be blocked," she said).
Mr. Magid and other researchers say the social networks fail to provide under-age users with tools that might protect them.
It has generally gone to greater lengths than rivals to keep adults and under-age users apart, at first allowing only college and high school students to join the service, and then largely restricting online communication to users at the same school.
The only question is: what should it change?I am shocked, shocked, to find that socialising is going onSoftware filters to block under-age users are unlikely to work, because young geeks will find ways around them and share them with all their friends.
Sites try to catch under-age users — "We are not burying our head in the sand," said Joe Sullivan, the chief security officer at Facebook — but verifying a young person's age over the Internet is a task that ranges from tricky to near impossible.
Internet companies have set up the rules against under-age users because they must comply with the federal Children's Online Privacy Protection Act, passed in 1998, which says Web sites that collect information from children younger than 13 must obtain parental consent.
Among veterans under age 65, VHA users were less likely to have insurance than VHA nonusers (60% versus 81%, p < 0.01).
Descriptive data are presented in Tables 1 and 2. A larger proportion of metformin monotherapy and combination therapy users were under age 80 years, compared with non-users.
Users under age 18 use Tinder in the same way as their adult counterparts, with just one caveat: they only see other minors between ages 13 and 17 and are not allowed to contact or see adult users.
A survey by Consumer Reports published in June found that there were 7.5 million users under age 13 (the site's threshold for membership); more than 5 million were under 10.
The company says its clients vary in age between 19 and 93, with over 55percentt of users under age 35.
