Analysis of the positive rate and justification of multi-site CT examinations in clinical emergency settings

Objective To explore the justification of emergency multi-site CT examinations and evaluate whether they conform to the principle of justification in radiological practice.Methods A retrospective analysis was performed on data of 1 989 cases of emergency multi-site CT examinations in our hospital from July to December 2024. The positive rates by person-time and by site were calculated, and differences in positive rates among different age groups, number of examined sites, applying departments, and reasons for consultation were compared.Results The total positive rate by site was 33.10% (2 423/7 321), which was significantly lower than the national standard of ≥60%. Compared with adults (33.75%), the positive rates of children (19.05%) and adolescents (15.38%) were lower (χ²=24.56, P<0.05). The positive rate of multi-site scans involving ≥6 sites was as high as 58.48%, significantly higher than that of other groups; the positive rate in the emergency intensive care unit (75.31%) and that for neurological disorders (57.36%) ranked the highest (χ²=313.07, P<0.05). The proportion of positive cases was 58.17% (1 157/1 989), but the positive rate by site was significantly lower than the positive rate by person-time (χ²=415.70, P<0.001).Conclusion The positive rate of emergency multi-site CT examinations is generally lower than the national standard, with an imbalance between radiation dose and diagnostic benefits and a risk of over-examination. It is necessary to strengthen justification evaluation to reduce unnecessary radiation exposure.