Table 3

Interobserver variability in measurement of degree of carotid stenosis on digital subtraction intra-arterial angiography, CT angiography, and MR angiography in asymptomatic arteries

Digital subtraction intra-arterial angiography
Observer 1
OperableNot operable
Observer 2:Operable21
Not operable2290.52*
MR angiography
Observer 3
OperableNot operableκ Value
Observer 4:Operable22
Not operable2280.43*
Spiral CT angiography
Observer 5
OperableNot operableκ Value
*κ Values are not reliable owing to small numbers of operable stenoses.
CT, computed tomography; MR, magnetic resonance.
Observer 6:Operable31
Not operable2280.62*