Am J Psychiatry 1994; 151:1340-1350
Copyright © 1994 by American Psychiatric Association
The ICD-10 clinical field trial for mental and behavioral disorders: results in Canada and the United States
DA Regier, CT Kaelber, MT Roper, DS Rae and N Sartorius
Division of Epidemiology and Services Research, NIMH, National Institutes of Health, Rockville, MD 20857.
OBJECTIVE: To help evaluate the impact of proposed revisions to the chapter
on mental and behavioral disorders for ICD-10, the World Health
Organization (WHO) Division of Mental Health organized an international
clinical field trial to evaluate draft clinical descriptions and diagnostic
guidelines. The authors compare interrater diagnostic reliability results
from this field trial for clinicians in Canada and the United States of
American with those from all other clinicians worldwide, as well as with
those from field trials conducted to evaluate drafts of DSM-III. METHOD:
Two or more clinicians at each clinical center independently evaluated each
patient, following a study protocol that allowed clinicians to list up to
six diagnoses. In Canada and the United States, 96 clinicians completed
1,781 assessments among 491 patients, and elsewhere in the world 472
clinicians completed 7,495 assessments among 1,969 patients. RESULTS:
Summary kappa coefficients at two-, three-, and four-character ICD-10 code
levels were 0.76, 0.65, and 0.52, respectively, for Canadian and U.S.
clinicians and 0.83, 0.75, and 0.62 for clinicians elsewhere. The mean
number of diagnoses per assessment for Canadian and U.S. clinicians was
2.1; for clinicians elsewhere it was 1.7. More multiple coding of diagnoses
for substance use disorders, mood (affective) disorders, and personality
disorders by Canadian and U.S. clinicians accounted for much of the
difference in diagnostic coding and in interrater reliability between them
and clinicians elsewhere. CONCLUSIONS: Interrater diagnostic reliability in
Canada and the United States was similar to that of clinicians worldwide
and also to results from the DSM-III field tests. Use of more multiple
coding of selected disorders by Canadian and U.S. clinicians may reflect
the influence of DSM-III and DSM-III-R, which encourage multiple diagnostic
entries and the use of separate multiaxial coding for personality
disorders, and may have reduced interrater concurrence for some categories.
Further, collaborative development of ICD-10 with DSM-IV has aligned these
two systems more closely.
