Effect of reader experience on variability, evaluation time and accuracy of coronary plaque detection with computed tomography coronary angiography.

OBJECTIVE: To assess the effect of reader experience on variability, evaluation time and accuracy in the detection of coronary artery plaques with computed tomography coronary angiography (CTCA).
METHODS: Three independent, blinded readers with three different experience levels twice labelled 50 retrospectively electrocardiography (ECG)-gated contrast-enhanced dual-source CTCA data sets (15 female, age 67.3 +/- 10.4 years, range 46-86 years) indicating the presence or absence of coronary plaques. The evaluation times for the readings were recorded. Intra- and interobserver variability expressed as kappa statistics and sensitivity, specificity, and negative and positive predictive values were calculated for plaque detection, with a consensus reading of the three readers taken as the standard of reference. A bootstrap method was applied in the statistical analysis to account for clustering.
RESULTS: Significant correlations were found between reader experience and, respectively, evaluation times (r = -0.59, p < 0.05) and intraobserver variability (r = 0.73, p < 0.05). The evaluation time significantly differed among the readers (p < 0.05). The observer variability for plaque detection, compared with the consensus, varied between kappa = 0.582 and kappa = 0.802. Variability of plaque detection was significantly smaller (p < 0.05) and more accurate (p < 0.05) for the most experienced reader.
CONCLUSION: Reader experience significantly correlated with observer variability, evaluation time and accuracy of coronary plaque detection at CTCA.