MDI Mental Developmental Index PDIPsychomotor Developmental Index SES Socioeconomic status TIS Total impairment score AIM The aim of this study was to evaluate cognitive and motor development in children with major congenital anomalies and the predictability of development at age 5 years.METHOD A prospective, longitudinal follow-up study was undertaken. The Dutch version of the Bayley Scales of Infant Development -Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) -were administered at the ages of 6, 12, and 24 months. The Revised Amsterdam Children's Intelligence Test -IQ and the Movement Assessment Battery for ChildrenTotal impairment score (TIS) were used at age 5 years. A total of 117 children participated in the study. After excluding 12 children who had a major chromosomal or syndromal abnormality, the analysis was limited to 105 children (50 females, 55 males). Seven groups of congenital anomalies were distinguished: (1) small intestinal anomalies; (2) abdominal wall defects, comprising gastroschisis and omphalocele; (3) oesophageal atresia; (4) congenital diaphragmatic hernia; (5) Hirschsprung disease; (6) anorectal malformations; and (7) miscellaneous diagnoses. Logistic regression analyses served to determine the ability of MDI and PDI to predict IQ and TIS at age 5 years.RESULTS At age five, 83.7% of 104 children had an IQ of 85 or above and 16.3% an IQ of less than 85. TIS was normal in 71.3% of 87 children, while 17.2% demonstrated a borderline score and 11.5% a definite motor problem. MDI and PDI scores showed equal sensitivity to predict IQ (p=0.004 at 6 and 12mo, p=0.001 at 24mo) and TIS (p<0.001 at 6 and 12mo, p=0.002 at 24mo). MDI and PDI were positively correlated with IQ and TIS; TIS was positively correlated with IQ.INTERPRETATION IQ scores at 5 years of age corresponded to Dutch population scores, but TIS scores differed significantly. Early development of children with major congenital anomalies is predictive of development at 5 years, which can guide individualized follow-up for this vulnerable group of children.About 2 to 3% of neonates in the Netherlands are born with major anatomical congenital anomalies, which are almost always detected shortly after birth. Most congenital anomalies are life-threatening and require early surgical intervention. 1 Examples are intestinal atresias, abdominal wall defects, such as gastroschisis and omphalocele, congenital diaphragmatic hernia, anorectal malformations, and Hirschsprung disease. Presentation may be isolated or as part of a spectrum of anomalies. Advances in surgery and perioperative care have reduced mortality rates (except for congenital diaphragmatic hernia) to approximately 10%. 2 Physical morbidity has become more prevalent, however, and may extend into adulthood. [3][4][5] None of these congenital anomalies has a cerebral component that might be primarily responsible for psychomotor delay. However, moderate to severe psychomotor delay and neurological impairment have been observed in some children with congenita...