Interrater reliability of the Clinical Dementia Rating in a multicenter trial.
OBJECTIVE
To test the interrater reliability of the Clinical Dementia Rating (CDR) in a multicenter clinical trial.


METHODS
Observational study.


METHODS
Training session for a multicenter trial of milameline, a direct muscarinic agonist, in the treatment of Alzheimer's disease.


METHODS
Twenty-four raters (physicians and nurses) familiar with drug trials and expert in the care of patients with Alzheimer's disease.


METHODS
Independent scoring of the CDR using four videotaped CDR interviews.


METHODS
Interrater reliability, as tested by the Kappa statistic


RESULTS
The overall interrater reliability was 0.62. Within the CDR domains, the global kappas ranged from 0.33 +/- 0.06 to 0.88 +/- 0.06.


CONCLUSIONS
The data support moderate to high overall interrater reliability but show important difficulties in the reliable assessment of early dementia.
Rockwood
K
K
Division of Geriatric Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.
Strang
D
D
MacKnight
C
C
Downer
R
R
Morris
J C
JC
D003704:Dementia / Q000145:classification* / Q000188:drug therapy; D004095:Dihydropyridines / Q000627:therapeutic use; D006801:Humans; D015337:Multicenter Studies as Topic; D018721:Muscarinic Agonists / Q000627:therapeutic use; D015588:Observer Variation; D010091:Oximes / Q000627:therapeutic use; D015203:Reproducibility of Results
D004095:Dihydropyridines; D018721:Muscarinic Agonists; D010091:Oximes; C084978:milameline