Brain SPECT: a controlled, blinded assessment of intra-reader and inter-reader agreement.
A detailed assessment of intra- and inter-reader variation in the interpretation of brain SPECT scans has been performed. A random sample was selected from scans performed at a community/teaching hospital in Seattle. Scans were interpreted independently by three experienced readers who were blinded to all patient information. Forty-eight scans were interpreted twice by each reader, for a total of 288 readings. Readers recorded detailed assessments of individual lesions and overall impressions using a standardized reporting form. Intra-observer agreement as reflected in per cent agreement for severity scores ranged from 65% to 100%. Intra-observer agreement on the 'overall impression' was very good for Alzheimer's pattern (kappa=0.73-1.00), and fair to good for the 'heterogeneous pattern' (kappa=0.30-0.63). Inter-observer agreement, as reflected in per cent agreement, ranged from 29% to 100%. Inter-observer agreement about the 'overall impression' was fair to moderate for Alzheimer's pattern (kappa=0.24-0.54) and was poor for the descriptors 'heterogeneous' and 'normal'. It is concluded that brain SPECT has great potential value in many important conditions. This study demonstrates a need for further work in the areas of pattern definition and reduction of observer variation.
Stockbridge
H L
HL
Washington State Department of Labor and Industries, Seattle, USA. halstock@u.washington.edu
Lewis
D
D
Eisenberg
B
B
Lee
M
M
Schacher
S
S
van Belle
G
G
Keifer
M
M
Brodkin
C A
CA
Buchwald
D
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging; D001921:Brain / Q000000981:diagnostic imaging*; D001927:Brain Diseases / Q000000981:diagnostic imaging*; D003072:Cognition Disorders / Q000000981:diagnostic imaging; D003704:Dementia / Q000000981:diagnostic imaging; D015161:Dementia, Multi-Infarct / Q000000981:diagnostic imaging; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009683:Nuclear Medicine / Q000592:standards*; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods* / Q000706:statistics & numerical data*