Perioperative risk factors were inconsistently associated with developmental outcomes .
INTERPRETATION The literature on children undergoing surgery in early infancy suggests that infants with a single ventricle are at highest risk of adverse developmental outcomes .
WHAT THIS PAPER ADDS Children with complex congenital heart disease ( CHD ) are at increased risk of impaired developmental outcome .
Children with single-ventricle CHD have worse outcomes than children with two-ventricle CHD .
Children with two-ventricle CHD gradually grow out of their initial developmental impairment .
Perioperative factors are inconsistently associated with outcome
AIM ( 1 ) To systematic ally review the literature on developmental outcomes from infancy to adolescence of children with complex congenital heart disease ( CHD ) who underwent early surgery ; ( 2 ) to run a meta-regression analysis on the Bayley Scales of Infant Development , Second Edition Mental Developmental Index and Psychomotor Developmental Index ( PDI ) of infants up to 24 months and IQs of preschool-aged children to adolescents ; ( 3 ) to assess associations between perioperative risk factors and outcomes .
How much loss to follow-up is acceptable in long-term randomised trials and prospective studies?
to test early  nutritional interventions  and prospect i ve observational cohorts . RCTs are generally accepted as method ologically the best approach for informing health policy . They can equalise unknown as well as known confounding factors and so can demonstrate causation ; they permit estimation of effect size and so can be used to assess likely
Perioperative risk factors were inconsistently associated with developmental outcomes .
INTERPRETATION The literature on children undergoing surgery in early infancy suggests that infants with a single ventricle are at highest risk of adverse developmental outcomes .
WHAT THIS PAPER ADDS Children with complex congenital heart disease ( CHD ) are at increased risk of impaired developmental outcome .
Children with single-ventricle CHD have worse outcomes than children with two-ventricle CHD .
Children with two-ventricle CHD gradually grow out of their initial developmental impairment .
Perioperative factors are inconsistently associated with outcome
AIM ( 1 ) To systematic ally review the literature on developmental outcomes from infancy to adolescence of children with complex congenital heart disease ( CHD ) who underwent early surgery ; ( 2 ) to run a meta-regression analysis on the Bayley Scales of Infant Development , Second Edition Mental Developmental Index and Psychomotor Developmental Index ( PDI ) of infants up to 24 months and IQs of preschool-aged children to adolescents ; ( 3 ) to assess associations between perioperative risk factors and outcomes .