Those defined as addicts should also meet at least one of three requirements: He or she always wants to use the Internet; feels annoyed or depressed if denied Internet use; or feels happier in the cyber, rather than the real, world.

Young people are surfing the internet.[File photo]

"As one of the few nationwide surveys, it is expected to comprehensively reflect the true picture of Internet addiction among Chinese youths," said Ke.

Last year, a Net-addicted teenager was allegedly beaten to death by counselors at an illegal rehabilitation camp in the Guangxi Zhuang autonomous region, which sparked a citizens' outcry on the lack of official supervision over such camps. Some officials and experts have accused rehab institutions of overstating the threat of Internet addiction for profit.

"The survey proves the threat of Internet addiction has not been exaggerated," said Wang Yanghu, head of Xi'an-based Yanghu Adolescents Quality Development Center, a rehab institute established in 2005.

"No matter the controversy on the issue, nobody can deny the fact that Internet addiction has affected the growth of adolescents. We are just trying to help them get rid of the problem," he said.