Johanna Månsson1,2, Karin Källén3, Eva Eklöf4,5, Fredrik Serenius6,7, Ulrika Ådén5,8,9, Karin Stjernqvist10. 1. Department of Neonatal care and Pediatric surgery, Skane University Hospital, Lund, Sweden. 2. Department of Clinical Sciences, Lund University, Lund, Sweden. 3. Centre of Reproductive Epidemiology, Lund University, Lund, Sweden. 4. Department of Medical Psychology, Karolinska University Hospital, Stockholm, Sweden. 5. Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. 6. Section for Pediatrics, Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden. 7. Department of Pediatrics, Institute of Clinical Sciences, Umeå University, Umeå, Sweden. 8. Neonatal Unit Karolinska University Hospital, Stockholm, Sweden. 9. Neonatal medicine Karolinska University Hospital, Stockholm, Sweden. 10. Department of Psychology, Lund University, Lund, Sweden.
Abstract
AIM: To investigate the ability of the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III), scores to predict later Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), performances in a cohort of children born extremely preterm. METHODS: 323 children, born <27 gestational weeks, were tested with the Bayley-III at corrected age 2.5 years and with the WISC-IV at 6.5 years. Regression analyses investigated the association between Bayley-III scores and WISC-IV full-scale intelligence quotient (IQ). The ability of Bayley-III Cognitive Index scores to predict low IQ was evaluated using receiver operating characteristic curves. RESULTS: Bayley-III Cognitive Index scores and IQ had a moderately positive correlation and accounted for 38% of the IQ variance. Using a Bayley-III cut-off score of 70, the sensitivity to detect children with IQ<70 was 18%, and false positive rate was 7%. A Bayley-III cut-off score of 85 corresponded to sensitivity and false positive rates of 44% and 7%, respectively. CONCLUSIONS: Results emphasise the relative importance of Bayley-III Cognitive Index scores as predictors of IQ. An 85 score cut-off for suspecting subnormal IQ is supported. A less conservative threshold would increase identification of true cases yet increase the risk of wrongly diagnosing children.
AIM: To investigate the ability of the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III), scores to predict later Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), performances in a cohort of children born extremely preterm. METHODS: 323 children, born <27 gestational weeks, were tested with the Bayley-III at corrected age 2.5 years and with the WISC-IV at 6.5 years. Regression analyses investigated the association between Bayley-III scores and WISC-IV full-scale intelligence quotient (IQ). The ability of Bayley-III Cognitive Index scores to predict low IQ was evaluated using receiver operating characteristic curves. RESULTS: Bayley-III Cognitive Index scores and IQ had a moderately positive correlation and accounted for 38% of the IQ variance. Using a Bayley-III cut-off score of 70, the sensitivity to detect children with IQ<70 was 18%, and false positive rate was 7%. A Bayley-III cut-off score of 85 corresponded to sensitivity and false positive rates of 44% and 7%, respectively. CONCLUSIONS: Results emphasise the relative importance of Bayley-III Cognitive Index scores as predictors of IQ. An 85 score cut-off for suspecting subnormal IQ is supported. A less conservative threshold would increase identification of true cases yet increase the risk of wrongly diagnosing children.