title: Representativeness of participants in a clinical trial for attention-deficit/hyperactivity disorder? Comparison with adults from a large observational study.
abstract: BACKGROUND
  Clinical trials have demonstrated that pharmacotherapies can safely treat attention-deficit/hyperactivity disorder (ADHD) in adulthood. Eligibility criteria in these trials may significantly limit their external validity by excluding a significant portion of adults with ADHD in the general population. In particular, exclusion criteria may frequently exclude individuals with comorbid mental health conditions, which are common in the adult ADHD population.
  
  
  METHODS
  We addressed the representativeness of clinical trials by comparing 146 adult clinical trial participants with DSM-IV ADHD and a community sample composed of 124 adults with DSM-IV ADHD and 123 non-ADHD controls. Subjects were compared on socioeconomic status, Hollingshead occupational code, cognitive measures, lifetime psychopathology, and Global Assessment of Functioning (GAF) scale ratings.
  
  
  RESULTS
  Adults with ADHD in the community sample had higher rates of lifetime psychiatric comorbidity, lower GAF scores, and lower occupational codes than those in the clinical trial. The clinical trial eligibility criteria would have excluded 61% of community sample adults with ADHD. This excluded portion of the community sample had higher rates of lifetime psychiatric comorbidity and lower GAF scores than clinical trial participants.
  
  
  CONCLUSIONS
  Adults with ADHD participating in the clinical trial had less evidence of functional impairment and endorsed less psychiatric comorbidity than the majority of community sample subjects with ADHD. This suggests that findings from clinical trials may have limited external validity for adults with ADHD in the general population, particularly for those adults with ADHD with the greatest burden of comorbid psychopathology.
authors.affiliation: Clinical and Research Programs in Pediatric Psychopharmacology and Adult ADHD, Massachusetts General Hospital, Ste 2000, 185 Alewife Brook Pkwy, Cambridge, MA 02138, USA. csurman@partners.org
authors.forename: Craig B H
authors.initials: CB
authors.lastname: Surman
authors.forename: Michael C
authors.initials: MC
authors.lastname: Monuteaux
authors.forename: Carter R
authors.initials: CR
authors.lastname: Petty
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Faraone
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Spencer
authors.forename: Nicole F
authors.initials: NF
authors.lastname: Chu
authors.forename: Joseph
authors.initials: J
authors.lastname: Biederman
mesh_terms: D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology* / Q000628:therapy; D002986:Clinical Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data; D003071:Cognition; D015897:Comorbidity; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D019370:Observation / Q000379:methods; D009790:Occupations / Q000706:statistics & numerical data; D018579:Patient Selection; D011569:Psychiatric Status Rating Scales; D012111:Residence Characteristics / Q000706:statistics & numerical data; D012494:Sampling Studies; D015983:Selection Bias; D012720:Severity of Illness Index; D012923:Social Class; D014481:United States
references.citation: Psychiatry Res. 1994 Jul;53(1):13-29
references.pmid: 7991729
references.citation: Arch Gen Psychiatry. 1993 Jul;50(7):565-76
references.pmid: 8317950
references.citation: Am J Psychiatry. 2005 Sep;162(9):1621-7
references.pmid: 16135620
references.citation: Compr Psychiatry. 1996 Nov-Dec;37(6):393-401
references.pmid: 8932963
references.citation: Biol Psychiatry. 2004 Apr 1;55(7):692-700
references.pmid: 15038997
references.citation: Am J Psychiatry. 2006 Oct;163(10):1720-9; quiz 1859
references.pmid: 17012682
references.citation: Arch Gen Psychiatry. 1982 Oct;39(10):1157-67
references.pmid: 7125846
references.citation: Arch Gen Psychiatry. 1982 Aug;39(8):879-83
references.pmid: 7103676
references.citation: Biol Psychiatry. 2005 Mar 1;57(5):456-63
references.pmid: 15737659
references.citation: Am J Psychiatry. 2006 Apr;163(4):716-23
references.pmid: 16585449
references.citation: Am J Psychiatry. 1993 Dec;150(12):1792-8
references.pmid: 8238632