Time of day does not affect radiologists' accuracy in breast lesion detection

Mammographic image reporting accuracy among radiologists varies. This study examines whether radiologists' accuracy in detecting breast lesions varies at different times throughout the day. Observers comprised of 69 experienced breast radiologists who reviewed 50 mammograms, consisting of 4 images each, of which 15 cases were abnormal. All the observers were grouped and assigned a specific hour, starting at 7:00am and finishing 8:00pm. They were asked to detect the lesion if present and mark their confidence rating (1-5) in a provided booklet. Demographic details were recorded including age, experience and average number of mammographic readings undertaken per year. Radiologists' performance was measured and compared in terms of sensitivity, specificity and receiver operating characteristic (ROC) scores. Kruskal-Wallis methods with Dunn's post-hoc test was performed. Mean ROC scores demonstrated no significant differences (p≥0.46) between groups performing at different times of the day. Also, no significant differences were noted for sensitivity (p≥0.78) or specificity (p≥0.99) when groups were compared with each other. The findings from the study suggest that although radiologists' performance varies slightly throughout the day, the exact time of day has no significant effect on radiologists' detection accuracy. The results found suggest further studies are required for these to investigate this effect.