κ Values: reference standard versus observers, intraobserver and interobserver variability
| Observer | Reference standard | A | B | C | D |
| A | 0.36 (0.42) | 0.56 | 0.43 (0.47) | 0.23 (0.15) | 0.28 (0.29) |
| B | 0.44 (0.40) | 0.43 (0.47) | 0.76 | 0.40 (0.32) | 0.18 (0.32) |
| C | 0.24 (0.22) | 0.23 (0.15) | 0.40 (0.32) | 0.88 | 0.24 (0.33) |
| D | 0.27 (0.36) | 0.28 (0.29) | 0.18 (0.32) | 0.24 (0.33) | 0.65 |
Reference standard, culture- or biopsy-proven cases.
Values in parentheses are observers' second assessment.