A retraction of a damning report on infant car seats may be a relief for parents who feared for their babies’ safety, but it is an embarrassment for a trusted consumer guide.

Consumer Reports said it was conducting an internal investigation into what may have gone wrong in its tests. The magazine originally reported that many seats had “failed disastrously” in test crashes at moderate speeds, but the National Highway Traffic Safety Administration said the tests were conducted at drastically higher speeds than the report had claimed.