The report by the Kaiser Family Foundation and Children's Digital Media Centers, based on a survey of parents, also found that kids in the 6 months to 6-year-old age group spend about two hours a day watching television, playing a video game or using a computer. That's roughly the same amount of time they spend playing outdoors and three times as long as they spend reading or being read to.
The report, which was being released Tuesday, found about one-third of children 6 and younger have TVs in their rooms and a similar proportion live in homes where a television is on most or all the time. In those "heavy TV households," 34 percent of children ages 4 to 6 can read, compared with 56 percent in homes where the TV is on less often.
"Watching TV is far inferior to playing with toys, being read to or playing with adults or talking with parents," said Dr. Henry Shapiro, chairman of developmental and behavior pediatrics at the American Academy of Pediatrics. "Watching TV without a parent is a junk experience, especially for young children."
The report found that 27 percent of 4 to 6 year olds use a computer each day. Those who do, spend about an hour at the keyboard.
Among kids in that age group, the report said half have played video games and one-quarter play several times a week or more. In a typical day, 24 percent of boys played video games compared with 8 percent of girls.
However, the report said, reading continues to be a regular part of children's lives. Almost 80 percent of children 6 and under read or are read to on any given day. Still, the report said, children spend only 49 minutes on average with books in a day compared with 2 hours and 22 minutes in front of a TV or computer screen.
The report's director, Victoria Rideout, said the findings show there are good parts about kids watching TV and using computers, but there are downsides, too.
"These kids will have a great advantage in terms of how media can aide their learning, but parents must understand the pitfalls," she said.
The report showed that parents have a largely positive view about TV and computers — 72 percent say computers mostly help in children's learning and 43 percent felt that way about television.
Twenty-seven percent said TV mostly hurts kids' learning and 21 percent said it doesn't have much effect one way or another.
Shapiro said that just because kids are sitting in front of TVs, computers and video games doesn't mean it's a trend for the worse. Rather, it makes them more accessible to information, and, therefore, learning.
But, he said, there is a downside — so much time in front of TVs can cause kids to become fat, eat junk foods and not get enough sleep or adult interaction.
The report is based on results of a national, random telephone survey of 1,065 parents of children ages 6 months to 6 years conducted from April to June. The margin of error is plus or minus 3 percentage points.
By Siobhan McDonough