Coefficient of variation (%) for each observer (intraobserver variability)
| Observer 1 | Observer 2 | Observer 3 | Observer 4 | Observer 5 | Observer 6 | |
|---|---|---|---|---|---|---|
| CBF (mL/100 g/min) | 2.56 | 0.35 | 6.60 | 0.60 | 2.17 | 2.34 |
| CBV (mL/100 g) | 1.31 | 0.33 | 1.86 | 8.38 | 3.87 | 2.19 |
| MTT (seconds) | 1.14 | 2.29 | —* | 5.77 | 3.78 | 1.52 |
Note:—CBF indicates cerebral blood flow; CBV, cerebral blood volume; MTT, mean transit time. Observer 1, radiology resident physician; observer 2, neuroradiology attending physician; observer 3, neurology attending physician; observer 4, neuroradiology fellow; observer 5, junior CT technologist; observer 6, senior CT technologist.
* Observer 3 had missing data for the MTT quantitative measurements on the repeated 10 CT perfusion datasets.