Reading times
Reading times per case were automatically recorded in the reading sessions. Mean reading time per case and its standard deviation was computed for every reader in both reading modes. Reading times exceeding 5 min were excluded from the analyses on the basis of the assumption that these excessively long reading times were the result of interruptions during the session. As a result, approximately 3% of all cases were excluded from the time analysis. Average reading times for the unaided session and the session with CAD were calculated. Paired reading times were compared by Wilcoxon signed rank testing. A P value of less than 0.05 was considered to indicate a statistically significant difference.