Table 3. Results of the multivariate analyses considering all "significant" variables from univariate analyses, comparing stroke patients to non-stroke patients (Analysis #1), and infarct side with contralateral side (Analysis #2), and comparison using a ROC analysis.
A ROC analysis allows to assess the "quality" of a model. More specifically, the area under the ROC curve is a measure of the accuracy of the model. A model with a area under the ROC curve equal to 1 is a perfect model, where the predicted values match exactly the observed values; if the area under to ROC curve decreases below 1, this corresponds to the accumulation of false positive and false negative predicted values; finally, if the area under the ROC curve is 0.5, the model is as good in its predictive ability as flipping a coin.
"Carotid Stroke Patients" versus "Non-Carotid Stroke Patients" (Analysis #1) | Infarct Side versus Contralateral Side (Analysis #2) | ||||
---|---|---|---|---|---|
CT features | Odds ratio (95% CI) | p value | CT features | Odds ratio (95% CI) | p value |
Lumen area [mm2] | 0.79 (0.71 – 0.88) | <0.001 | |||
wall volume [100 mm3] | 4.08 (2.24 – 7.43) | <0.001 | wall volume [100 mm3] | 1.58 (1.00 – 2.49) | 0.017 |
number of calcium clusters | 0.31 (0.15 – 0.63) | 0.001 | fibrous cap thickness | 0.11 (0.06 – 0.16) | 0.013 |
number of lipid clusters | 1.22 (1.08 – 1.39) | 0.002 | number of lipid clusters | 1.58 (1.15 – 2.18) | 0.005 |
location of largest lipid cluster | 0.74 (0.61 – 0.89) | 0.002 | location of largest lipid cluster | 0.83 (0.67 – 1.02) | 0.048 |
Area under ROC curve = 0.796 | Area under ROC curve = 0.832 |
CI stands for confidence interval