Correlation between cumulative Onyx vials and radiation dose ratio (last session dose to first session dose)
| Correlation | rho | P value |
| Onyx vials and DAP ratio on frontal plane | 0.6829 | 0.0018 |
| Onyx vials and DAP ratio on lateral plane | 0.7056 | 0.0011 |
| Onyx vialsl and CAK ratio on frontal plane | 0.4325 | 0.0730 |
| Onyx vials and CAK ratio on lateral plane | 0.5049 | 0.0326 |
CAK, cumulative air kerma; DAP, dose–area product.