Table 2.
Intra and Interobserver agreement between two separate readings made by the experienced and novice observer for the presence of three continuous variables in contrast enhanced pulmonary angiography exams know to be positive for pulmonary embolism.
| CE-MRA Imaging Measurement | Number of emboli measured |
ICC | 95 % C.I. | p value |
|---|---|---|---|---|
| Clot/vessel ratio (R1) | 54 | 0.38 | 0.12−0.58 | 0.0022 |
| Clot/vessel ratio (R2) | 54 | 0.31 | 0.06−0.54 | 0.0093 |
| Clot/vessel ratio (Interobserver) | 54 | 0.40 | 0.15−0.60 | 0.0011 |
| Main PA (R1) | 56 | 0.88 | 0.81−0.93 | <.00001 |
| Main PA (R2) | 56 | 0.81 | 0.70−0.89 | <.00001 |
| Main PA (Interobserver) |
56 | 0.66 | 0.49−0.79 | <.00001 |
| RV/LV Ratio (R1) | 56 | 0.88 | 0.80−0.93 | <.00001 |
| RV/LV Ratio (R2) | 56 | 0.78 | 0.65−0.86 | <.00001 |
| RV/LV Ratio (Interobserver) |
56 | 0.65 | 0.48−0.78 | <.00001 |
Abbreviations: R1- Reader one, R2- Reader 2, Intraobserver- Interobserver variability, Clot/vessel ratio- clot/vessel lumen signal intensity ratio, Main PA- transverse measurement of the main pulmonary artery maximum diameter, RV/LV ratio- the modified 4 chamber (straight axial) measurement of right ventricle/left ventricle minor axis ratio, ICC- intraclass correlation coefficient, 95 % C.I.−95% confidence interval about estimated ICC, p value – p-value from subsequent hypothesis test.