Table 1.

Cognitive and Adaptive Outcome in Children with UCD Age 3-16 Years

Age GroupAge 3-5 YearsAge 6-16 Years
Age at OnsetNeonatal 1
Late 2
Neonatal 1
Late 2
AssessmentWASI/WPPSI-III 3 composite scores 4 (SD)
  • Verbal IQ
81.3 (16.6)101.7 (24.4)72.9 (14.3)94.3 (21.7)
  • Performance IQ
77.7 (15.0)95.6 (17.4)74.4 (11.7)89.5 (20.4)
  • Full scale IQ
77.7 (16.3)99.6 (22.6)71.4 (12.8)94.1 (22.0)
ABAS-II 5 general adaptive composite 4 (SD)
73.2 (31.2)91.4 (23.6)66.0 (17.9)84.4 (21.6)

Clinical presentation in 1st month


Clinical onset after 1st month or diagnosis based on family history


Wechsler Abbreviated Scales of Intelligence / Wechsler Preschool and Primary Scale of Intelligence, 3rd Edition


Clinically significant difference between groups for cognitive and adaptive outcome


Adaptive Behavior Assessment System, 2nd Edition

From: Urea Cycle Disorders Overview

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