title: Trajectories and predictors of the development of very young boys with fragile X syndrome.
abstract: OBJECTIVE
  To describe the development of young boys with fragile X syndrome (FXS).
  
  
  METHODS
  Fifty-five boys (aged 8-48 months at study entry) with the full mutation FXS received multiple developmental assessments.
  
  
  RESULTS
  As expected, the boys' rate of development was significantly lower than chronological age expectations. No evidence of slowing in the rate of development was found. Autistic behavior was negatively associated with development, but maternal IQ was not. Developmental delays were evident in some domains as early as 9 months; however, initial detection of delays is complicated by measures and criteria used. Developmental age scores at 31 months of age were related to scores obtained at 61 months of age only in the global composite and visual reception domain.
  
  
  CONCLUSIONS
  Developmental delays are evident in some infants with FXS as young as 9 months of age. Pediatric psychologists need to be informed about the developmental profiles in young children with FXS to accurately diagnose, treat, and support these children and their families.
authors.affiliation: Department of Psychology, University of South Carolina, Barnwell College, Columbia, SC 29208, USA. jane.roberts@sc.edu
authors.forename: Jane E
authors.initials: JE
authors.lastname: Roberts
authors.forename: Jean B
authors.initials: JB
authors.lastname: Mankowski
authors.forename: John
authors.initials: J
authors.lastname: Sideris
authors.forename: Barbara Davis
authors.initials: BD
authors.lastname: Goldman
authors.forename: Deborah D
authors.initials: DD
authors.lastname: Hatton
authors.forename: Penny L
authors.initials: PL
authors.lastname: Mirrett
authors.forename: Grace T
authors.initials: GT
authors.lastname: Baranek
authors.forename: J Steven
authors.initials: JS
authors.lastname: Reznick
authors.forename: Anna C J
authors.initials: AC
authors.lastname: Long
authors.forename: Donald B
authors.initials: DB
authors.lastname: Bailey
mesh_terms: D000367:Age Factors; D001321:Autistic Disorder / Q000175:diagnosis* / Q000523:psychology; D002675:Child, Preschool; D015897:Comorbidity; D002658:Developmental Disabilities / Q000175:diagnosis* / Q000523:psychology / Q000628:therapy; D003937:Diagnosis, Differential; D018479:Early Intervention, Educational; D005600:Fragile X Syndrome / Q000175:diagnosis* / Q000523:psychology / Q000628:therapy; D006801:Humans; D007223:Infant; D007360:Intelligence; D008137:Longitudinal Studies; D008297:Male