Effect of Shift, Schedule, and Volume on Interpretive Accuracy: A Retrospective Analysis of 2.9 Million Radiologic Examinations.

Purpose To determine whether there is an association between radiologist shift length, schedule, or examination volume and interpretive accuracy. Materials and Methods This study was institutional review board approved and HIPAA compliant. A retrospective analysis of all major discrepancies from a 2015 quality assurance database of a teleradiology practice was performed. Board-certified radiologists provided initial preliminary interpretations. Discrepancies were identified during a secondary review by a practicing radiologist or through an internal quality assurance process and were vetted through a consensus radiology quality assurance committee. Unique anonymous radiologist identifiers were used to link the discrepancies to radiologists' shifts and schedules. Data were analyzed by using analysis of variance, t test, or χ test. Results A total of 4294 major discrepancies resulted from 2 922 377 examinations (0.15%). There was a significant difference for shift length (P < .0001) and volume (P < .0001) for shifts with versus those without discrepancies. On average, errors occurred a mean (± standard deviation) of 8.97 hours ± 2.28 into the shift (median, 10 hours; interquartile range, 2.0 hours). Significantly more errors occurred late in shifts than early (P < .0001), peaking between 10 and 12 hours. The number of major discrepancies in a single shift ranged from one to four, with a significant difference in the number of discrepancies as a function of study volume (volume for all shifts, 67.60 ± 60.24; volume for shifts with major discrepancies, 118.96 ± 66.89; P < .001). Despite a trend for more discrepancies after more consecutive days worked, the difference was not significant (P = .0893). Conclusion Longer shifts and higher diagnostic examination volumes are associated with increased major interpretive discrepancies. These are more likely to occur later in a shift, peaking after the 10th hour of work. RSNA, 2017.