Skip to main content

Table 5 Summary of statistical results for “low-dose” and “ultra-low-dose” CT protocols in patients (≥ 80-kg body weight)

From: Ultra-low-dose chest CT protocol during the second wave of COVID-19 pandemic: a double-observer prospective study on 250 patients to evaluate its detection accuracy

Statistical results: Low-dose CT (45 mAs) Ultra-low-dose CT (22 mAs)
Observer 1 Observer 2 Observer 1 Observer 2
Value 95% CIa Value 95% CI Value 95% CI Value 95% CI
Sensitivity 97.84% 93.82 to 99.55% 97.84% 93.82 to 99.55% 93.53% 88.06 to 97.00% 96.40% 91.81 to 98.82%
Specificity 42.86% 9.90 to 81.59% 42.86% 9.90 to 81.59% 42.86% 9.90 to 81.59% 42.86% 9.90 to 81.59%
Positive predictive value (PPV) 97.14% 94.71 to 98.48% 97.14% 94.71 to 98.48% 97.01% 94.47 to 98.41% 97.10% 94.63 to 98.45%
Negative predictive value (NPV) 50.00% 19.64 to 80.36% 50.00% 19.64 to 80.36% 25.00% 10.32 to 49.12% 37.50% 15.13 to 66.88%
Positive likelihood ratio 1.71 0.90 to 3.25 1.71 0.90 to 3.25 1.64 0.86 to 3.11 1.69 0.89 to 3.21
Negative likelihood ratio 0.05 0.01 to 0.21 0.05 0.01 to 0.21 0.15 0.05 to 0.44 0.08 0.02 to 0.28
Accuracy 95.21% 90.37 to 98.05% 95.21% 90.37 to 98.05% 91.10% 85.26 to 95.17% 93.84% 88.62 to 97.14%
  1. aCI confidence interval