While The Baby Einstein Company does not explicitly make educational claims, it notes on its web page that the Baby Wordsworth DVD is a "playful introduction to words and sign language."
The new study, published in the Archives of Pediatrics & Adolescent Medicine, put the DVD to the test in a group of one- and two-year-olds.
For six weeks, 88 children were randomly assigned to either watch it a few times a week or not at all. Researchers then tested the language skills in each group based on how many words the kids knew according to their parents and how well they did in a lab test.
At the end of the period, toddlers who had watched the DVD fared no better than those who hadn't.
Children in both groups understood about 20 of the 30 words highlighted in the DVD, on average, and spoke 10. Their general language development showed no difference, either.
The researcher also asked parents about their kids' television viewing before entering the study. The earlier a child started watching Baby Einstein DVDs, it turned out, the smaller his or her vocabulary was.
The finding is in line with earlier research, said Rebekah Richert, a psychologist at the University of California, Riverside, who led the study. But it is unclear if the DVDs themselves are responsible. Parents who place their kids in front of the screen could be trying to remedy slow language development, or they could be using the DVDs as baby sitters, cutting back on social stimulation.
"A lot of children, particularly when they're young, seem to have these kinds of (DVDs)," Richert told Reuters Health. "My take-home message would be to encourage live interaction between parent and child."
Although it is not well understood how watching television affects language, Richert and colleagues write in their report, the American Academy of Pediatrics recommends that children younger than 2 stay away from the screen.
(Reuters. March 4, 2010.)