Table 2 Calculation of the interobserver agreement (kappa coefficient)
From: Is overexpression of HER-2 a predictor of prognosis in colorectal cancer?
| Â | Â | Â | Pathologist 2 | Total | ||
|---|---|---|---|---|---|---|
| Â | Â | Â | 1+ | 2+ | 3+ | 1.00 |
Pathologist 1 | 1+ | Count (n) | 7 | 1 | 0 | 8 |
| Â | Â | Pathologist 1 (%) | 87.5 | 12.5 | 0 | 100 |
| Â | Â | Pathologist 2 (%) | 100 | 11.1 | 0 | 44.4 |
| Â | Â | % of Total | 38.9 | 5.6 | 0 | 44.4 |
| Â | 2+ | Count (n) | 0 | 8 | 0 | 8 |
| Â | Â | Pathologist 1 (%) | 0 | 100 | 0 | 100 |
| Â | Â | Pathologist 2 (%) | 0 | 88 | 0 | 44.4 |
| Â | Â | % of Total | 0 | 44 | 0 | 44.4 |
| Â | 3+ | Count (n) | 0 | 0 | 2 | 2 |
| Â | Â | Pathologist 1 (%) | 0 | 0 | 100 | 100 |
| Â | Â | Pathologist 2 (%) | 0 | 0 | 100 | 11.1 |
| Â | Â | % of Total | 0 | 0 | 11.1 | 11.1 |
| Â | Total | Count (n) | 7 | 9 | 2 | 18 |
| Â | Â | Pathologist 1 (%) | 38.9 | 50 | 11.1 | 100 |
| Â | Â | Pathologist 2 (%) | 100 | 100 | 100 | 100 |
| Â | Â | % of Total | 38.9 | 50 | 11.1 | 100 |
Symmetric measures | Â | |||||
| Â | Value | Standard error (a) | Approximate T (b) | Approximate significance | Â | Â |
Kappa coefficient | 0.906 | 0.092 | 4.894 | 0.00 | Â | Â |
Number of valid cases (n) | 18 | Â | Â | Â | Â | Â |