title: Predictive validity of the Bayley, Third Edition at 2 years for intelligence quotient at 4 years in preterm infants.
abstract: OBJECTIVE
  To determine the predictive validity of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) at age 2 years for cognitive abilities in preschool children born at ≤ 30 weeks' gestation.
  
  
  METHODS
  This prospective regional study included all 187 liveborn infants ≤ 30 weeks' gestation born between July 2005 and June 2006. Of the 172 children who survived to 4 years, 156 (91%) were evaluated at 2 and 4 years. A socioeconomically matched term control group also was recruited to provide normative data. The predictive validity of the Bayley-III cognitive and language scales for the Weschler Preschool and Primary Scale of Intelligence-III (WPPSI-III) was examined through correlation coefficients and sensitivity and specificity of the Bayley-III to predict normal and abnormal cognitive outcomes.
  
  
  RESULTS
  Correlations of the WPPSI-III intelligence quotient (IQ) score with the Bayley-III cognitive and language scores were .81 and .78, respectively. The preterm children were classified as normal (Bayley Scales of Infant Development-Third Edition [BSID-III] cognitive score or WPPSI-III IQ score not lower than 1 SD below the control group mean), mild to moderately delayed (scores between 1 and 2 SD deviations below the control group mean), or severely delayed (scores greater than 2 SD below the control group mean). At 2 and 4 years, 126 (81%) preterm children retained the same developmental classification.
  
  
  CONCLUSIONS
  In contrast with previous editions of the BSID, the Bayley-III has strong predictive validity for WPPSI-III IQ at age 4 years in preterm children. This has important implications for more timely evaluation of perinatal interventions, establishment of guidelines for neonatal care, and counseling parents.
authors.affiliation: *Department of Pediatrics, Upstate Medical Center, SUNY, Syracuse, NY; †Department of Neonatology, Crouse Hospital, Syracuse, NY.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Bode
authors.forename: Diane B
authors.initials: DB
authors.lastname: DʼEugenio
authors.forename: Barbara B
authors.initials: BB
authors.lastname: Mettelman
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Gross
mesh_terms: D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007234:Infant, Premature / Q000502:physiology*; D007360:Intelligence / Q000502:physiology*; D008297:Male; D009483:Neuropsychological Tests / Q000592:standards*; D011594:Psychometrics / Q000295:instrumentation*; D015203:Reproducibility of Results; D014888:Wechsler Scales