Less than one-third of prescription medicines used to treat children have been formally approved by the U.S. Food and Drug Administration for use in youngsters, but many parents believe all such drugs are FDA-approved, says a survey released Monday by the University of Michigan C.S. Mott Children's Hospital National Poll on Children's Health.

Among the findings:

* 83 percent of parents believed the last medication prescribed for their child was FDA-approved.
* 94 percent of parents feel a child's doctor is responsible for disclosing whether a medication is not FDA-approved for use in children.
* 77 percent want their child's doctor to prescribe only medicines that are FDA-approved for use in children.
* Women are more likely than men to want their child's doctor to prescribe only medicines with pediatric labeling.
* Parents with less education are more likely to want only FDA-approved medicine for their children.

"FDA labeling is very important to parents, but that's a problem when only one-third of medicines have FDA approval for use in children," Dr. Matthew M. Davis, director of the National Poll on Children's Health, said in a prepared statement. "The solution to that is to either get more medicines that are FDA-approved by increasing clinical studies, or working to help physicians and parents negotiate the situation when physicians want to use medicines that are safe and effective, but may not have FDA approval."