Statistical analysis
Variables are described in terms of mean or median and standard
deviation (SD).
Chi-square tests were applied to analyze the differences between the
three imaging techniques in terms of distribution of correct and
incorrect responses (accuracy) and in terms of distribution of agreement
between time point one and two. We calculated sensitivity and
specificity values [with 95% confidence intervals (CIs)] for all
three imaging techniques. Sensitivity refers to the ability of an
evaluator to correctly classify an image as ‘diseased’, while
specificity as the ability to correctly classifiy as ‘disease-free’12.