Table 2.
Intra- and interobserver reliability of the modified Waldenstrom, Herring, Salter-Thompson and Catterall classification systems
| Classification | Sample Size n* |
Intraobserver | Interobserver | ||
|---|---|---|---|---|---|
| Observed Agreement | Kappa k (95% CI) |
Observed Agreement | Kappa k (95% CI) |
||
| Modified Waldenstrom | 100 | 72% | 0.67 (0.59, 0.75) | 80% | 0.76 (0.67, 0.85) |
| Herring | 27 | 89% | 0.65 (0.34, 0.96) | 86% | 0.62 (0.27, 0.98) |
| Salter–Thompson | 22 | 41% | 0.07 (− 0.12, 0.27) | 46% | 0.24 (0.01, 0.48) |
| Catterall | 54 | 48% | 0.10 (− 0.02, 0.22) | 74% | 0.41 (0.17, 0.64) |
*n number of hips that could be appropriately classified based on disease stage