How Helpful Is Expanded Newborn Screening?
New Screening Method Is Good, but Parents Need More Information
WebMD News Archive
False Positives Create True Problems
But her study finds that false-positive results understandably cause parents a great deal of stress. "We have to recognize that false-positive results can be extremely stressful unless the test and conditions are fully explained to the family by an expert," Waisbren tells WebMD.
"Sometimes, parents are just told, 'No news is good news,' or not told anything. Those parents are much more stressed than those who get the news through a face-to-face conversation with their doctor or another expert, especially when there's a positive finding -- whether it's correct or a false positive."
Her study tracked the families of 50 babies identified with a condition through this expanded newborn screening and 33 others whose children were diagnosed through a medical exam alone. During the children's' first six months of life, 28% of those getting the expanded test were hospitalized, compared with 55% of those clinically evaluated.
Children with false-positive results were twice as likely to be hospitalized than children with normal results.
Mothers of those tested with tandem mass spectrometry reported less stress than those who were clinically evaluated, but those who received a false-positive reading were twice as stressed as those getting normal results.
Individually, the conditions screened with tandem mass spectrometry are rare, but collectively, affect about one in 4,000 babies, Waisbren says.
The bottom line: As use of this test expands -- and it's currently being considered in eight other states -- there's an increased need for more education about it before a child's birth, she says.
Learn About the Test Early
Agreed, adds Celia I. Kaye, MD, PhD, who was not involved in the study. She is genetics advisor to the National Newborn Screening and Genetics Resource Center and professor of pediatrics at the University of Texas Health Science Center in San Antonio.
"The single most important piece of advice is to discuss testing with the pediatrician early, so that the parents know what the test is for and are aware of the problems of false-positive results and false negatives," Kaye tells WebMD.
"Parents should also be aware of the fact that there are many, many disorders for which newborn screening is not done -- even expanded newborn screening tests for only a small percentage of all of the possible disorders of childhood. Parents who receive a positive result on a screening test need to discuss the test result with their pediatrician, or a metabolic specialist, as soon as possible.