title: Parsing the familiality of oppositional defiant disorder from that of conduct disorder: a familial risk analysis.
abstract: BACKGROUND
  Family risk analysis can provide an improved understanding of the association between attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD), attending to the comorbidity with conduct disorder (CD).
  
  
  METHODS
  We compared rates of psychiatric disorders in relatives of 78 control probands without ODD and CD (Control, N=265), relatives of 10 control probands with ODD and without CD (ODD, N=37), relatives of 19 ADHD probands without ODD and CD (ADHD, N=71), relatives of 38 ADHD probands with ODD and without CD (ADHD+ODD, N=130), and relatives of 50 ADHD probands with ODD and CD (ADHD+ODD+CD, N=170).
  
  
  RESULTS
  Rates of ADHD were significantly higher in all three ADHD groups compared to the Control group, while rates of ODD were significantly higher in all three ODD groups compared to the Control group. Evidence for co-segregation was found in the ADHD+ODD group. Rates of mood disorders, anxiety disorders, and addictions in the relatives were significantly elevated only in the ADHD+ODD+CD group.
  
  
  CONCLUSIONS
  ADHD and ODD are familial disorders, and ADHD plus ODD outside the context of CD may mark a familial subtype of ADHD. ODD and CD confer different familial risks, providing further support for the hypothesis that ODD and CD are separate disorders.
authors.affiliation: Massachusetts General Hospital, Boston, MA 02114, USA. cpetty@partners.org
authors.forename: Carter R
authors.initials: CR
authors.lastname: Petty
authors.forename: Michael C
authors.initials: MC
authors.lastname: Monuteaux
authors.forename: Eric
authors.initials: E
authors.lastname: Mick
authors.forename: Samantha
authors.initials: S
authors.lastname: Hughes
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Small
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Faraone
authors.forename: Joseph
authors.initials: J
authors.lastname: Biederman
mesh_terms: D000293:Adolescent; D001008:Anxiety Disorders / Q000453:epidemiology / Q000523:psychology; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D016022:Case-Control Studies; D002648:Child; D015897:Comorbidity; D019955:Conduct Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D005190:Family / Q000523:psychology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D019964:Mood Disorders / Q000453:epidemiology / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D018570:Risk Assessment; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000523:psychology; D055815:Young Adult