Combining information from multiple sources in the diagnosis of autism spectrum disorders.
BACKGROUND
Standard case criteria are proposed for combined use of the Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule to diagnose autism and to define the broader category of autism spectrum disorders.


METHODS
Single and combined Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule algorithms were compared to best estimate diagnoses in four samples: U.S. (n = 960) and Canadian (n = 232) participants 3 years and older, U.S. participants younger than 36 months (n = 270), and U.S. participants older than 36 months with profound mental retardation (n = 67).


RESULTS
Sensitivities and specificities of 80% and higher were obtained when strict criteria for an autism diagnosis using both instruments were applied in the U.S. samples, and 75% or greater in the Canadian sample. Single-instrument criteria resulted in significant loss of specificity. Specificity was poor in the sample with profound mental retardation. Lower sensitivity and specificity were also obtained when proposed criteria for broader spectrum disorders were applied.


CONCLUSIONS
The Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule make independent, additive contributions to the judgment of clinicians that result in a more consistent and rigorous application of diagnostic criteria.
Risi
Susan
S
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom. Electronic address: srisi@umich.edu.
Lord
Catherine
C
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Gotham
Katherine
K
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Corsello
Christina
C
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Chrysler
Christina
C
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Szatmari
Peter
P
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Cook
Edwin H
EH
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Leventhal
Bennett L
BL
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
Pickles
Andrew
A
Drs. Risi and Lord and Ms. Gotham are with the University of Michigan Autism and Communication Disorders Center, Ann Arbor; Dr. Corsello is with the Department of Psychiatry, University of California, San Diego; Ms. Chrysler and Dr. Szatmari are with the Offord Centre for Child Studies, McMaster University, Hamilton, Canada; Drs. Cook and Leventhal are with the Department of Psychiatry, University of Illinois at Chicago; Dr. Pickles is with the University of Manchester, United Kingdom.
D020817:Asperger Syndrome / Q000175:diagnosis / Q000235:genetics; D001321:Autistic Disorder / Q000175:diagnosis* / Q000235:genetics*; D002648:Child; D003710:Demography; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007255:Information Services / Q000706:statistics & numerical data*; D008297:Male; D011795:Surveys and Questionnaires