When added to the two to three hours many parents already admit to allowing at home, preschoolers in child care may be spending more than a third of the about 12 hours they are awake each day in front of the electronic baby sitter, said Dr. Dimitri Christakis, a pediatrician at Children's Hospital and Regional Medical Center in Seattle and a researcher at the University of Washington.
That's double the TV time he found in a previous study based on parental reports of home viewing, according to findings published Monday in the journal Pediatrics. The study is the first to look at TV watching in child care in more than 20 years.
The figures come from a telephone survey of 168 licensed child care programs in Michigan, Washington, Florida and Massachusetts. Christakis said he thought television use was probably underreported.
Of the child care programs surveyed, 70 percent of home-based child cares and 36 percent of centers said children watch TV daily. The children were watching TV, DVDs and videos. The study did not track what kind of programs were shown.
"It's not what parents have signed up for," Christakis said. "I'm not sure how many parents are aware of this."
The American Academy of Pediatrics discourages any television viewing of any kind in the first 2 years of life and recommends a daily limit of 1 to 2 hours of quality programming for older children.
Children go to day care to develop social skills, build on cognitive abilities and enjoy imaginative play, as well as allowing their parents to work, Christakis said.
"We know what's good for children and we know what's not," Christakis said. "High quality preschool can make a very, very positive difference. We're so far from meeting that, that we really have a lot of work to do."
His research found a difference between the amount of TV watching at home daycares and larger child care centers, although both reported some TV time.
The study found that among preschool-aged children, those in home-based day cares watched TV for 2.4 hours per day on average, compared to 24 minutes in centers. Toddlers watched an average of 1.6 hours in home care and about 6 minutes in centers. Only home-based day cares admitted putting infants in front of the TV, for an average of 12 minutes a day.
"It's alarming to find that so many children in the United States are watching essentially twice as much television as we previously thought," he said.
Other research has connected excessive TV watching during the preschool years with language delay, obesity, attention problems and aggression.
Dr. Michael Rich, director of the Center on Media and Child Health at Children's Hospital Boston, wasn't surprised by the findings in this study but he was forgiving of the parents and child care providers who put kids in front of the TV.
"In general, we still have a culture that sees television as benign," said Rich, who is also an associate professor of pediatrics at Harvard University. "This is an area where we're learning more and more all the time."
He compared society's growing knowledge of the impact of TV on child development to the early days of seat belt use. Today's parents and child care providers grew up on TV, Rich said, so it's understandable that they do not recognize the problem.
"We can always do better," he said.
Christakis said one of the main problems with TV for young children is that it takes away time that could otherwise be spent playing outside, being read to, playing with blocks and talking with adults and other children.
The study did not include passive TV time, when the TV is on in the background but no one is actively watching it. Christakis said any time a TV is on, children speak less and adults interact with them less frequently.
Instead of urging parents to turn off the TV, President Barack Obama might want to start sending the same message to child care providers, Christakis said.
"Hopefully this will serve as a wake-up call," he said.