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.