Developmental Screens: False Positives Still at Risk.
"Children overreferred by developmental screens perform substantially lower than true-negative children on measures of intelligence, language, and academic achievement--the three best predictors of school success," said Dr. Glascoe of Vanderbilt University Nashville.
"Overreferred children also carry more psychosocial risk factors," Dr. Glascoe added.
"Children with false-positive screening results are clearly an at-risk and under-performing group for whom diagnostic testing appears less an unnecessary expense and more a potentially beneficial service," she argued.
Dr. Glascoe based her comments on data collected on a nationwide sample of 511 parents and children aged 7 months to 7 years. The children were studied at four day care centers and four public school systems, including school-based Head Start and Even Start programs in five states.
All of the children were screened with at least two developmental tests, including the Brigance Screens, the Battelle Developmental Inventory Screening Test, the Denver-II, and/or the Parents' Evaluation of Developmental Status (PEDS), she said.
The false-positive rates among these tests range from about 22% with the PEDS and the Battelle to 45% using the Denver-II, Dr. Glascoe noted.
The screening tests were followed with a battery of diagnostic intelligence, language, and academic achievement tests, she said.
Of the 511 children included in the study 216 (42%) failed one or more of the screening tests but were found not to have a disability on the diagnostic panel (false-positives).
Another 220 (43%) children passed all of the developmental tests and did not have disabilities (true negatives).
The remaining 75 children (15%) were either false negatives (passed all of the screens but had disabilities) or true positives (failed one or more of the screens and had disabilities).
Compared with the children whose results were true negatives, the children who had false-positive screening tests performed significantly lower on diagnostic measures and had IQs averaging 9-14 points less.
The children with false-positive results also were 2 to 5 times more likely to score below the 25th percentile on adaptive behavior, language skills, and academic measures than were the true negatives, and were 6.7 times more likely to score that low on intelligence tests, Dr. Glascoe reported.
The 25th percentile is the cutoff that is typically used for placement of children in remedial reading and math programs under school-based Title I programs, she said.
The performance on diagnostic measures of false-positive children continued to be significantly lower than that of true-negative children even after adjusting for socioeconomic differences between the two groups.
Children who turn out to have false-positive scores on such tests should be closely monitored and referred when appropriate to developmental services, Dr. Glascoe advised.
For a listing of accurate developmental-behavioral screening tests, she referred physicians to an article from the AAP Section on Developmental and Behavioral Pediatrics at www.dbpeds.org/articles/dbtesting.
|Printer friendly Cite/link Email Feedback|
|Author:||TUCKER, MIRIAM E.|
|Publication:||Family Practice News|
|Date:||Sep 15, 2000|
|Previous Article:||Newborn Screening: Report Signals Work Ahead.|
|Next Article:||To Assess Developmental Delay, Listen to Parents.|