Incidence of injury according to tackle type
| Injury | Total, n (/1000 tackles) | Concussion, n (/1000 tackles) | Neck injury, n (/1000 tackles) | Stinger, n (/1000 tackles) | Shoulder injury, n (/1000 tackles) | Nasal fracture, n (/1000 tackles) | |
| Tackle with incorrect head position | + | 22 (69.4) | 10 (31.5) | 3 (9.5) | 12 (37.9) | 1 (3.2) | 2 (6.3) |
| − | 295 | 307 | 314 | 305 | 316 | 315 | |
| Tackle with correct head position | + | 10 (2.7) | 4 (1.1) | 1 (0.3) | 4 (1.1) | 0 (0) | 1 (0.3) |
| − | 3643 | 3649 | 3652 | 3649 | 3653 | 3652 | |
| Degree of freedom | 1 | 1 | 1 | 1 | 1 | 1 | |
| Pearson χ2 value | 162.1 | 77.0 | 24.5 | 87.5 | 11.5 | 14.1 | |
| Continuity correction | 153.9 | 68.5 | 16.2 | 89.3 | 2.4 | 7.2 | |
| Likelihood ratio | 74.5 | 34.7 | 10.9 | 43.7 | 5.1 | 6.5 | |
| Fisher’s exact test, P | <0.01* | <0.01* | <0.01* | <0.01* | 0.08 | 0.02* | |
| Phi coefficient | 0.20 | 0.14 | 0.08 | 0.16 | 0.05 | 0.06 | |
| OR (95% CI) | 27.2 (12.7 to 57.9) | 29.7 (9.3 to 95.3) | 34.9 (3.6 to 336.4) | 35.9 (11.5 to 112.0) | NE | 23.2 (2.1 to 256.4) | |
| Power of analysis | 1.0 | 0.99 | 0.72 | 1.0 | NE | 0.54 | |
*Significance.
NE, not estimated.