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School-age outcomes in children who were extremely low birth weight from four international population-based cohorts
Saroj Saigal1, Lya den Ouden, Dieter Wolke
1Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada. saigal@mcmaster.ca
Insights
Learning and school problems are common in extremely low birth weight (ELBW) survivors across multiple countries. These challenges, including cognitive and achievement deficits, necessitate educational support for over half of these children.
Area of Science:
- Pediatrics
- Developmental Psychology
- Educational Psychology
Background:
- Extremely low birth weight (ELBW) survivors face potential long-term developmental and academic challenges.
- International comparisons are crucial to understand variations in outcomes for ELBW populations.
Purpose of the Study:
- To investigate differences in learning and school problems among extremely low birth weight (ELBW) survivors and reference children across international cohorts.
- To compare the prevalence of cognitive and achievement deficits in ELBW children in New Jersey, Ontario, Bavaria, and Holland.
Main Methods:
- Longitudinal follow-up of 532 ELBW survivors (500-1000g birth weight) from four international cohorts (New Jersey, Ontario, Bavaria, Holland).
- Psychometric assessments of cognitive status and academic achievement administered between ages 8-11 years.
- Data on special educational assistance and grade repetition collected from parents, with country-specific norm adjustments.
Main Results:
- Significant variations in cognitive and achievement scores were observed across cohorts, with New Jersey showing the lowest deficit rates and Bavaria performing lower in achievement.
- Proportions of children with normal IQ ranged from 44%-62%, reading 46%-81%, arithmetic 31%-76%, and spelling 39%-65%.
- Over half of all ELBW children in the study required special educational assistance or grade repetition, indicating widespread school difficulties.
Conclusions:
- School difficulties are a significant and common sequela of extremely low birth weight (ELBW) across diverse international settings.
- These findings highlight the substantial social and economic implications of long-term educational support needs for ELBW survivors.
Objective:
The aim of this study was to determine whether learning and school problems in extremely low birth weight (ELBW) and reference children differ between cohorts in different countries.
Methods:
Participants were 4 international population-based cohorts of ELBW survivors who were 500 to 1000 g birth weight from New Jersey, central-west Ontario, Bavaria, and Holland (n = 532) and were followed longitudinally from birth. Psychometric data were collected independently and prospectively and included at least 1 measure of cognitive status and 1 measure of achievement administered to the children between the ages of 8 and 11 years. Adjustments were made for comparison of all measures based on reference norms within each country. Information on special educational assistance and grade repetition was obtained from the parents.
Results:
The overall follow-up rate was 84% (range: 74%-90%; n = 436). The proportion of children who performed within the normal range (> or =85) were as follows: IQ between 44% and 62%; reading between 46% and 81%; arithmetic between 31% and 76%; and spelling between 39% and 65%. Children from New Jersey had the lowest rates of cognitive and achievement deficits, and Bavarian children did less well in achievement scores relative to their peers and other cohorts. Despite these differences, more than half of all cohorts required special educational assistance and/or repeated a grade.
Conclusions:
School difficulties were found to be a serious sequelae of ELBW in all 4 countries, an observation that has social and economic implications.
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