title: Birth weight and cognitive function at age 11 years: the Scottish Mental Survey 1932.
abstract: OBJECTIVE
  To examine the relation between birth weight and cognitive function at age 11 years, and to examine whether this relation is independent of social class.
  
  
  METHODS
  Retrospective cohort study based on birth records from 1921 and cognitive function measured while at school at age 11 in 1932. Subjects were 985 live singletons born in the Edinburgh Royal Maternity and Simpson Memorial Hospital in 1921. Moray House Test scores from the Scottish Mental Survey 1932 were traced on 449 of these children.
  
  
  RESULTS
  Mean score on Moray House Test increased from 30.6 at a birth weight of <2500 g to 44.7 at 4001-4500 g, after correcting for gestational age, maternal age, parity, social class, and legitimacy of birth. Multiple regression showed that 15.6% of the variance in Moray House Test score is contributed by a combination of social class (6.6%), birth weight (3.8%), child's exact age (2.4%), maternal parity (2.0%), and illegitimacy (1.5%). Structural equation modelling confirmed the independent contribution from each of these variables in predicting cognitive ability. A model in which birth weight acted as a mediator of social class had poor fit statistics.
  
  
  CONCLUSIONS
  In this 1921 birth cohort, social class and birth weight have independent effects on cognitive function at age 11. Future research will relate these childhood data to health and cognition in old age.
authors.affiliation: Geriatric Medicine, Department of Clinical and Surgical Sciences, University of Edinburgh, 21 Chalmers Street, Edinburgh EH3 9EW, UK.
authors.forename: S D
authors.initials: SD
authors.lastname: Shenkin
authors.forename: J M
authors.initials: JM
authors.lastname: Starr
authors.forename: A
authors.initials: A
authors.lastname: Pattie
authors.forename: M A
authors.initials: MA
authors.lastname: Rush
authors.forename: L J
authors.initials: LJ
authors.lastname: Whalley
authors.forename: I J
authors.initials: IJ
authors.lastname: Deary
mesh_terms: D000367:Age Factors; D001724:Birth Weight; D002648:Child; D002657:Child Development / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007086:Illegitimacy; D007231:Infant, Newborn; D007361:Intelligence Tests; D016014:Linear Models; D008297:Male; D010298:Parity; D012189:Retrospective Studies; D012923:Social Class; D018709:Statistics, Nonparametric