Washington, Oct 1 : Young children who spend two or more hours a day in front of the idiot box are at an increased risk of developing behavioural problems and poor social skill, warn researchers at the Johns Hopkins Bloomberg School of Public Health.

The finding is based on an analysis of data for 2,707 children between 2.5 to 5.5 years of age collected from the Healthy Steps for Young Children national evaluation by the researchers.

According to the study, the impact of TV viewing on a child’s behaviour and social skills varied by the age at which the viewing occurred. More importantly, heavy television viewing that decreased over time was not associated with behaviour or social problems.

After the analysis, it was found that sixteen percent of parents reported that their children watched two hours or more of television daily at 2.5 years of age (early exposure), while 15 percent reported that their children watched two hours or more of television daily at 5.5 years of age (concurrent exposure).

One in five parents reported that their children watched two hours or more of television daily at both 2.5 years and at 5.5 years of age (sustained exposure).

Sustained exposure to television was associated with behavioural problems. However, early exposure that was subsequently reduced was not a risk for behaviour problems. Concurrent viewing was associated with fewer social skills, while sustained and early viewing had less of an impact on social skill development.

The researchers also found that having a television in the child’s bedroom at 5.5 years of age was associated with behavioural problems, poor social skills and poor sleep. Forty-one percent of the children included in the study had a television in his or her bedroom.

“A number of studies have demonstrated negative effects of heavy television viewing. However, timing of exposure is an important consideration as reducing viewing to acceptable levels can reduce the risk of behavioural and social problems,” Kamila Mistry, MPH, lead author of the study and a doctoral candidate in the Bloomberg School’s Department of Population, Family and Reproductive Health, said.

“Children who reduced their viewing by 5.5 years of age were not at greater risk for behaviour and social problems. It is vital for clinicians to emphasize the importance of reducing television viewing in early childhood among those children with early use,” said Cynthia Minkovitz, MD, MPP, senior author of the study and associate professor with the School’s Department of Population, Family and Reproductive Health.

The study is published in the October 2007 issue of Pediatrics. (With inputs from ANI)