Table 3.
Inter- and intra-observer reproducibility studies on grading of invasive breast cancer
| Study | Cases | Readers | Inter-observer variation | Intra-observer variation |
|---|---|---|---|---|
| Theissig et al., 1990 [12] | 166 | 3 | Complete agreement 72.3%. Kappa 0.57 | - |
| Robbins et al., 1995 [57] | 50 | 5 | Complete agreement 83.3%. Kappa 0.73 | - |
| Frierson et al., 1995 [58] | 75 | 6 | Kappa 0.43 to 0.74 | - |
| Jacquemier et al., 1998 [59] | 24 | 21 | Complete agreement 69%. Kappa 0.53 | - |
| Sikka et al., 1999 [60] | 40 | 3 | Kappa 0.68 to 0.83 | - |
| Anderson et al., 2000 [25] | 52 | 2 | Kappa 0.54 | - |
| Boiesen et al., 2000 [9] | 93 | 7 | Kappa 0.54 | - |
| Reed et al., 2000 [30] | 613 | 2 | Kappa 0.69 | - |
| Page et al., 2001 [61] | 425 | 2 | Complete agreement 76% | - |
| Meyer et al., 2005 [62] | 7 | 49 | Kappa 0.50–0.59 | - |
| Chowdhury et al., 2006 [63] | 50 | 5 | Mean polychoric correlation 0.8 | - |
| Longacre et al., 2006 [64] | 35 | 13 | Kappa 0.5 to 0.7 | - |
| Ellis et al., 2006 [65] | 12 | 600 | Kappa 0.45 to 0.53 (figures after application of guidelines) | - |
| Bueno-de-Mesquita et al., 2010 [66] | 694 | 2 | Kappa 0.56 | |
| Postma et al., 2013 [67] | 310 | 2 | Kappa 0.80 | |
| Rabe et al., 2019 [68] | 100 | 6 | Kappa 0.58–0.85 | Mean Kappa 0.77 |
| Ginter et al., 2020 [69] | 143 | 6 | Kappa 0.50 | - |