Table 2:
Diagnostic accuracy of the 3 observers for the detection of cranial AVFs (n = 31), with DSA serving as the reference standarda
| Detection of AVF | Observer 1, Method 1b | Observer 2, Method 1b | Observer 3, Method 1b | Observer 1, Method 2c | Observer 2, Method 2c | Observer 3, Method 2c | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| True-positive, true-negative | 19 | 10 | 21 | 10 | 18 | 7 | 20 | 10 | 21 | 10 | 18 | 7 |
| False-positive, false-negative | 0 | 2 | 0 | 0 | 3 | 3 | 0 | 1 | 0 | 0 | 3 | 3 |
| Sensitivity (%) (95% CI) | 90 (70–99) | 100 (81–100) | 86 (63–96) | 95 (76–100) | 100 (81–100) | 86 (63–96) | ||||||
| Specificity (%) (95% CI) | 100 (69–100) | 100 (66–100) | 70 (35–92) | 100 (69–100) | 100 (66–100) | 70 (35–92) | ||||||
| PPV (%) (95% CI) | 100 (80–100) | 100 (81–100) | 86 (63–96) | 100 (80–100) | 100 (81–100) | 86 (63–96) | ||||||
| NPV (%) (95% CI) | 83 (57–94) | 100 (66–100) | 70 (35–92) | 91 (60–98) | 100 (66–100) | 70 (35–92) | ||||||
| Fleiss κ | 0.619 (Substantial agreement) | 0.661 (Substantial agreement) | ||||||||||
Note:—PPV indicates positive predictive value; NPV, negative predictive value.
a
The Fleiss κ for interobserver agreement is shown per method.
b
Method 1, color-mapping only.
c
Method 2, color-mapping and dynamic subtraction rendering of 4D-CTA.