The Walt Disney Company is going toe-to-toe with the University of Washington in Seattle after a study by the university's researchers suggested that exposure to DVDs and videos for babies, including Disney's Baby Einstein, could be associated with poorer language development.

One of the team, professor of paediatrics Dimitri Christakis, was widely quoted as saying “I would rather babies watch American Idol than these videos.”

Robert Iger, Disney's chief executive, says the study's “methodology is doubtful, its data seem anomalous and the inferences it posits unreliable”. In a letter to the university, he accused it of issuing a “deliberately misleading, irresponsible and derogatory” press release. “Whether your university is comfortable associating its name with analysis of this quality is, of course, your decision,” he wrote. “And I would not be reaching out to you if all that was at stake was a poorly done academic study.”

What is at stake is a million-dollar industry in such products for babies. A full set of Baby Einstein DVDs costs US$369.99. Baby Einstein packaging says it “is not designed to make babies smarter”, but detractors claim such products are marketed as educational.

“Disney is expecting the brand to bring in $1 billion by 2010,” says psychologist Susan Linn of Harvard Medical School in Boston, Massachusetts, and a founder of the Boston-based Campaign for a Commercial-Free Childhood, a group opposed to marketing to children. In May 2006 the campaign asked the US Federal Trade Commission (FTC) to investigate Baby Einstein and Brainy Baby of Alpharetta, Georgia, another leading manufacturer of baby videos, for “engaging in deceptive acts and practices”. They were backed by the American Academy of Pediatrics and the American Academy of Child and Adolescent Psychiatry. The complaint is still being considered.

Linn sees the entire 'baby industry' becoming more litigious. “We can expect more of this kind of corporate intimidation,” she warns. “Disney is on the defensive and they're going to come out swinging.”

The study, published online earlier this month (F. Zimmerman et al. J. Pediatr. doi:10.1016/j.jpeds.2007.04.071; 2007), found that babies aged 8 to 16 months who watched such videos scored lower than other babies on the Communicative Development Inventory (CDI), a standard tool used to gauge language development in infants. Babies that watched an hour a day scored 17 points lower on the CDI scale — corresponding to knowing seven fewer words than a typical baby in the study who did not watch the videos, the researchers say.

Lead author Frederick Zimmerman suggests several explanations for their findings, including the fact that parents worried about their child's language development might turn to the videos. But “it is possible that heavy viewing of baby DVDs/videos has a deleterious effect on early language development,” he says.

The study was press-released by his university under the headline “Baby DVDs, videos may hinder, not help, infants' language development”. University president Mark Emmert has refused to retract the press release and says he stands behind the research. “The findings were considered significant enough to be reported in a major journal, and as a public institution we feel duty bound to make the public aware of these findings,” he says.

What babies watch: it may not make a difference. Credit: AMERICAN IDOL/19 TELEVISION/FOX/FREMANTLE MEDIA/KOBAL

Deborah Linebarger, an expert in child development and television at the University of Pennsylvania in Philadelphia, was asked by Disney to defend Baby Einstein to the FTC. Although believing such products can be useful, she declined. “I have concerns that anything called Baby Einstein, Genius, etcetera, is exploitive of a vulnerable population,” she says.

Despite having “some methodological issues” with the paper, she says: “There are some valid conclusions in it that warrant additional research. I'm cautious, but it makes sense.”