Skip to main content

Advertisement

Table 5 Results of the paired t-test

From: Development of a zoomorphic test specimen for constancy testing on digital X-ray systems in veterinary radiology

No. of X-ray image Entrance dose change [%] Tube current–time product [mAs] Tube voltage change [kVp] P-value from paired t-test Protocol
2 0 6.3 0 0.185 A
3 − 21 5 0 < 0.001 A
4 − 37 4 0 < 0.001 A
5 − 49 3.2 0 < 0.001 A
6 + 27 8 0 0.678 A
7 + 39 6.3 + 3 < 0.001 A
8 − 31 6.3 − 3 0.012 A
9 − 48 6.3 − 5 0.002 A
10 − 68 6.3 − 8 0.038 A
11 0 6.3 0 0.013 B
12 0 6.3 0 0.024 C
  1. P-values of the paired t-test for the paired comparison between the VGAS of the reference image (1) and the images 2–12. The null hypothesis is that there is no difference between the VGAS. Image 11 and 12 were taken with a different image processing; protocol B (head) and protocol C (abdomen) instead of protocol A (thorax)