title: Research Review: Executive function deficits in fetal alcohol spectrum disorders and attention-deficit/hyperactivity disorder - a meta-analysis.
abstract: BACKGROUND
  Attention-deficit/hyperactivity disorder (ADHD)-like symptoms are common in fetal alcohol spectrum disorders (FASD). FASD and ADHD groups both display executive function impairments; however, there is ongoing debate whether the pattern and magnitude of executive function deficits differs between these two types of disorders.
  
  
  METHODS
  An electronic literature search was conducted (PubMed, PsychInfo; 1972-2013) to identify studies comparing the executive functioning of children with FASD with ADHD or control groups. FASD groups included those with and without dysmorphy (i.e., FAS, pFAS, ARND, and other FASD diagnoses). Effect sizes (Hedges' g, standardized mean difference) were calculated. Random effects meta-analytic models were performed using the metafor package for R.
  
  
  RESULTS
  Fifty-one studies met inclusion criteria (FASD N = 2,115; ADHD N = 453; controls N = 1,990). Children with FASD showed the strongest and most consistent deficits in planning, fluency, and set-shifting compared to controls (Hedges' g = -0.94, -0.78) and children with ADHD (Hedges' g = -0.72, -0.32). FASD was associated with moderate to large impairments in working memory, compared to controls (Hedges' g = -.84, -.58) and small impairments relative to groups with ADHD (Hedges' g = -.26). Smaller and less consistent deficits were found on measures of inhibition and vigilance relative to controls (Hedges' g = -0.52, -0.31); FASD and ADHD were not differentiated on these measures. Moderator analyses indicated executive dysfunction was associated with older age, dysmorphy, and larger group differences in IQ. Sex and diagnostic system were not consistently related to effect size.
  
  
  CONCLUSIONS
  While FASD is associated with global executive impairments, executive function weaknesses are most consistent for measures of planning, fluency, and set-shifting. Neuropsychological measures assessing these executive function domains may improve differential diagnosis and treatment of FASD.
authors.affiliation: Department of Psychology, Concordia University, Montreal, QC, Canada.
authors.forename: Danielle
authors.initials: D
authors.lastname: Kingdon
authors.affiliation: Department of Psychology, Concordia University, Montreal, QC, Canada.
authors.forename: Christopher
authors.initials: C
authors.lastname: Cardoso
authors.affiliation: Department of Psychology, Concordia University, Montreal, QC, Canada.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: McGrath
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D056344:Executive Function / Q000502:physiology*; D063647:Fetal Alcohol Spectrum Disorders / Q000503:physiopathology*; D006801:Humans
keywords: Fetal alcohol spectrum disorders; attention-deficit/hyperactivity disorder; executive function; meta-analysis; neuropsychology