Comparison of radiation dose between the two periods
| Period 1 1998/9 | Period 2 2002/3 | p Value | |
|---|---|---|---|
| *Fisher’s exact test; †Mann-Whitney U test. | |||
| Skull radiograph | 140 | 54 | <0.001* |
| Number (%) of two views | 111 (79) | 45 (83) | 0.69* |
| Number (%) of three views | 29 (21) | 9 (17) | |
| Skull radiograph total radiation dose | 15.16 mSv | 5.76 mSv | <0.001† |
| Computed tomography | 3 | 1 | 0.36* |
| Total radiation dose | 21.16 mSv | 7.76 mSv | <0.001† |