Multiple logistic regression analysis results examining inappropriateness of CT and MRI according to several explanatory variables
Variable | OR | 95% CI | P |
Model 1: appropriate CT examinations Log likelihood=−237.60; χ²=173.65 (6 df); P<0.0001, no of observations=613 | |||
Contrast agent use | |||
No | 1.00* | ||
Yes | 0.17 | 0.10 to 0.28 | <0.001 |
Clinical hypothesis confirmed by CT | |||
No | 1.00* | ||
Yes | 11.9 | 6.88 to 20.8 | <0.001 |
More than one CT examination performed during hospital stay | |||
No | 1.00* | ||
Yes | 0.24 | 0.14 to 0.42 | <0.001 |
Anatomical scan region | |||
Head | 1.00* | ||
Whole body | 0.69 | 0.35 to 1.32 | 0.268 |
Muscoloskeletal system | 0.02 | 0.05 to 0.84 | 0.028 |
Vascular system | 3.21 | 0.97 to 10.58 | 0.055 |
Model 2: inappropriate MRI examinations Log likelihood=−70.83; χ²=54.41 (4 df); P<0.0001, no of observations=220 | |||
Clinical hypothesis confirmed by MRI | |||
No | 1.00* | ||
Yes | 5.14 | 1.68 to 15.70 | 0.004 |
More than one MRI examination performed during hospital stay | |||
No | 1.00* | ||
Yes | 0.11 | 0.04 to 0.29 | <0.001 |
Anatomical scan region | |||
Head | 1.00* | ||
Muscoloskeletal system/spine/extremities MRI | 0.08 | 0.02 to 0.25 | <0.001 |
Admission type | |||
Planned | 1.00* | ||
Urgent | 0.57 | 0.17 to 1.90 | 0.368 |
*Reference category.