title: Social variables predict gains in cognitive scores across the preschool years in children with birth weights 500 to 1250 grams.
abstract: OBJECTIVE
  To determine the extent that social variables influence cognitive development of very low birth weight (VLBW) infants across the preschool years.
  
  
  METHODS
  Participants were VLBW (500-1250 g) children enrolled in the Caffeine for Apnea of Prematurity randomized trial between 1999 and 2004. We investigated the relationships between 4 potential social advantages: higher maternal education, higher paternal education, caregiver employment, and 2 biologic parents in the same home--and gain in cognitive scores. Cognitive assessments were performed at the corrected ages of 18 months (Mental Development Index score on the Bayley Scales of Infant Development II) and 5 years (Full Scale IQ on the Wechsler Preschool and Primary Scale of Intelligence III). Cognitive gain was computed by subtracting each individual 18-month Mental Development Index score from the corresponding Full Scale IQ at 5 years.
  
  
  RESULTS
  Data were available for 1347 children. Mean (SD) cognitive scores were 90.8 (15.7) at 18 months and 98.9 (14.5) at 5 years. Multivariable regression showed that higher maternal education, higher paternal education, and caregiver employment had independent and additive effects of similar size on cognitive gain (P < .001); the mean cognitive gain between 18 months and 5 years increased by 3.6 points in the presence of each of these advantages. When all 3 were present, cognitive scores improved on average by 10.9 points compared with children without any of these advantages.
  
  
  CONCLUSIONS
  In VLBW children, a count of 3 social advantages strongly predicts gains in cognitive scores across the preschool years.
authors: Department of Obstetrics and Gynecology, The University of Melbourne, Melbourne, Australia; Neonatal Services and Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia. Electronic address: brett.manley@thewomens.org.au.
authors: Brett J
authors: BJ
authors: Manley
authors: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors: Robin S
authors: RS
authors: Roberts
authors: Department of Obstetrics and Gynecology, The University of Melbourne, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia; Research Office, The Royal Women's Hospital, Melbourne, Australia; Department of Pediatrics, The University of Melbourne, Melbourne, Australia.
authors: Lex W
authors: LW
authors: Doyle
authors: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada; Division of Neonatology, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania, Philadelphia, PA.
authors: Barbara
authors: B
authors: Schmidt
authors: Murdoch Childrens Research Institute, Melbourne, Australia; Department of Pediatrics, The University of Melbourne, Melbourne, Australia.
authors: Peter J
authors: PJ
authors: Anderson
authors: McGill University, Montreal, Quebec, Canada.
authors: Keith J
authors: KJ
authors: Barrington
authors: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors: Birgitta
authors: B
authors: Böhm
authors: Soroka Medical Center, Beer Sheva, Israel.
authors: Agneta
authors: A
authors: Golan
authors: Department of Neonatology, Emma Children's Hospital AMC, Amsterdam, The Netherlands.
authors: Aleid G
authors: AG
authors: van Wassenaer-Leemhuis
authors: Department of Obstetrics and Gynecology, The University of Melbourne, Melbourne, Australia; Neonatal Services and Newborn Research Centre, The Royal Women's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia.
authors: Peter G
authors: PG
authors: Davis
mesh_terms: D001724:Birth Weight / Q000502:physiology*; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight / Q000502:physiology*; D007360:Intelligence / Q000502:physiology*; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies