Sensitivity, specificity, accuracy, and interobserver agreement in detecting stroke

Imaging StudyTrue-PositiveFalse-PositiveFalse-NegativeTrue-NegativeSensitivity (%)Specificity (%)Accuracy (%)κ
Nonenhanced CT
    Any sign182384369.
    Lost cortical ribbon115156143.492.378.50.528
    Lost insular ribbon73196326.995.075.80.591
    Basal ganglia hypodensity1510125655.885.076.70.478
    Dense artery610205623.
    ATLANTIS/ASPECTS hypoattenuations11577139114145.293.785.30.594
    TTP review1942986092076.5*75.675.7*0.526
    MTT review1972885793077.6*76.376.5*0.618
    rCBF review15811196110762.290.9*86.0*0.516
    rCBV review12889126112950.592.7*85.4*0.505
    Computerized automated method1739481112468.292.3*88.1*NA
  • Note.—Follow-up CT or MR imaging was the criterion standard. Globally, accuracy was significantly greater with PCT than with nonenhanced CT: TTP and MTT maps are significantly more sensitive, whereas rCBF and rCBV maps were significantly more specific. NA indicates not applicable.

  • * Significantly superior to nonenhanced CT (any sign).