Background: Although night-shift performance is well studied among residents, the diagnostic accuracy of board-certified senior radiologists remains insufficiently characterized. Senior radiologists (5 years posttraining) often deliver final interpretations without secondary review, yet their vulnerability to fatigue and circadian disruption is not well quantified. Objectives: To systematically assess diagnostic accuracy during night shifts among experienced radiologists and evaluate factors influencing performance, including age, practice setting, and temporal patterns across the night. Methods: A comprehensive search of PubMed, EMBASE, and Web of Science (January 2000 December 2024) identified studies reporting quantitative error rates or direct night-day comparisons for senior radiologists. Data synthesis followed PRISMA 2020 guidelines. Random-effects models were applied; heterogeneity was assessed using the I2 statistic, and publication bias via funnel plots and Eggers regression.