Children imitate what they see on the screen, both good and bad behavior. This effect of television and video programming can be applied to positively impact children’s behavior according to a study published online in Pediatrics on Feb. 18. The study, “Modifying media content for preschool children: A randomized controlled trial,” was led by Dimitri Christakis, MD, MPH, director of the Center for Child Health, Behavior and Development at Seattle Children’s Research Institute.

Media diet study

Researchers in Seattle studied 565 families with children aged three to five years who spent at least some time watching TV or video content each week. Half of the families were randomly assigned to a “media diet” intervention while the other half, “the control group,” received a nutritional diet intervention designed to promote healthier eating habits. “For the media diet, we coached families on how to substitute prosocial and educational programs for violent ones,” said Christakis.

What is prosocial content?

Prosocial programming encourages children to be kind and to share, and portrays adults as dependable.

The intervention addressed all screen time (TV, DVDs and videos, computer, video games, handheld devices, etc.), but the primary focus was on TV and videos because this accounts for the vast majority of screen time in preschool-aged children.

How families followed a media diet

Families in both groups kept media diaries and provided details on the amount of time spent watching TV, videos and other types of screen time. The research team distributed monthly program guides and a sample DVD of prosocial content that would appeal to boys, girls and diverse populations. Families were also steered to Common Sense Media, which provides ratings for family movies, TV shows, websites and video games.

The intervention did not attempt to reduce the number of hours of screen time for the children, but it did encourage a positive media diet and co-viewing with parents. A case manager followed up with families regularly for 12 months. At six months and 12 months, the children in the media diet intervention group were spending significantly less time on violent programming than they did at the start of the study, compared to the control group.

Both the intervention and control groups increased viewing time slightly during the study, but the control group increased its minutes of violent content, while the intervention group increased its minutes of prosocial and educational content.

At six months, the children in the intervention group demonstrated significantly less aggression and more prosocial behavior compared to the control group, and the effect lasted throughout the 12 months. Christakis and team concluded that such an intervention can positively impact child behavior.

Content as important as quantity

“We often focus on how much kids watch and don’t focus enough on what they watch,” Christakis said. “While too many children watch too much TV, this study shows that content is as important as quantity.  It isn’t just about turning off the TV, it’s about changing the channel.”

Christakis said the public health description for a media diet is that it’s a harm reduction approach, similar to a needle exchange, condom distribution or a methadone clinic for heroin addicts. “The media diet reduces the risks associated with TV,” he said.

What about parents who didn’t take part in the study? “Parents could absolutely implement the media diet on their own,” said Christakis.

Implement a media diet in your home: Dr. Christakis’ tips for parents

• Keep a media diary to make sure you’re aware of the TV and movies your child is watching
• Choose less violent and more prosocial content for your kids to watch, via sites like Common Sense Media
• Watch TV and movies with your children, so that you’re more aware of the content


Promoting health early child development: An update and research agenda from the Christakis Lab, January 2013
New study links violent videos to sleep problems in preschool children, August 2012, Pediatrics
Infant brains more engaged when playing with interactive toys: Study, July 2012, Journal of Pediatrics
Powerpuff Girls vs. Mister Rogers’ Neighborhood: Media impact on early childhood development, January 2012, TEDxRainier