title: High IQ May "Mask" the Diagnosis of ADHD by Compensating for Deficits in Executive Functions in Treatment-Naïve Adults With ADHD.
abstract: OBJECTIVE
  To evaluate and compare the performance of adults with ADHD with high and standard IQ in executive functions (EF) tasks.
  
  
  METHODS
  We investigated the neuropsychological performance of 51 adults with ADHD, compared with 33 healthy controls (HC) while performing a wide battery of neuropsychological tests that measure executive functioning. Adults with clinical diagnosis of ADHD were divided into two groups according to their IQ level (IQ ≥ 110-ADHD group with more elevated IQ, and IQ < 110-ADHD group with standard IQ).
  
  
  RESULTS
  The ADHD group with standard IQ presented a worse executive functioning compared with the HC group in the following measures: Stroop 2 ( p = .000) and 3 ( p = .000), Trail Making Test (TMT) B ( p = .005), Wisconsin Card-Sorting Test (WCST)-perseverative errors ( p = .022) and failures to maintain set ( p = .020), Continuous Performance Test (CPT)-omission errors ( p = .005) and commission errors ( p = .000), and Frontal Assessment Battery (FAB)-conceptualization ( p = .016). The ADHD group with more elevated IQ presented only impairments in the CPT-commission errors ( p = .019) when compared with the control group.
  
  
  CONCLUSIONS
  Adults with ADHD and more elevated IQ show less evidence of executive functioning deficits compared with those with ADHD and standard IQ, suggesting that a higher degree of intellectual efficiency may compensate deficits in executive functions, leading to problems in establishing a precise clinical diagnosis.
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Ana Luiza Vidal
authors.initials: AL
authors.lastname: Milioni
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Tiffany Moukbel
authors.initials: TM
authors.lastname: Chaim
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Mikael
authors.initials: M
authors.lastname: Cavallet
authors.affiliation: 2 Mackenzie Presbyterian University, São Paulo, Brazil.
authors.forename: Nathalya Moleda
authors.initials: NM
authors.lastname: de Oliveira
authors.affiliation: 3 Clinical Psychiatrist, Private Practice, São Paulo, Brazil.
authors.forename: Marco
authors.initials: M
authors.lastname: Annes
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Dos Santos
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Mario
authors.initials: M
authors.lastname: Louzã
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Maria Aparecida
authors.initials: MA
authors.lastname: da Silva
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Carmen Silvia
authors.initials: CS
authors.lastname: Miguel
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Mauricio Henriques
authors.initials: MH
authors.lastname: Serpa
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Zanetti
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Geraldo
authors.initials: G
authors.lastname: Busatto
authors.affiliation: 1 University of São Paulo, Brazil.
authors.forename: Paulo Jannuzzi
authors.initials: PJ
authors.lastname: Cunha
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000523:psychology; D003071:Cognition / Q000502:physiology; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D009483:Neuropsychological Tests; D055815:Young Adult
keywords: ADHD; IQ; executive functioning