Table 2.
Statistical comparison of the tested linacs for the average and largest range of deviations, and the maximum standard deviations of the results (worst reproducibility) over each of the tested components
| Average range | Largest range | Worst reproducibility | ||
|---|---|---|---|---|
| EPID Sag (mm) | Cross-plane | 0.17 | 0.32 (L#11) | 0.04 (L#11) |
| In-plane | 1.00 | 2.68 (L#7) | 0.08 (L#10) | |
| Gantry Sag (mm) | Cross-plane | 0.42 | 0.63 (L#11) | 0.10 (L#10) |
| In-plane | 0.72 | 0.82 (L#12) | 0.15 (L#8) | |
| SDD (mm) | 3.57 | 8.65 (L#11) | 1.15 (L#2) | |
| EPID and Collimator Skew (degrees) | 0.15 | 0.17 (L#9) | 0.09 (L#3) | |
| EPID Tilt (degrees) | Cross-plane | 0.02 | 0.04 (L#10) | 0.01 (L#7) |
| In-plane | 0.06 | 0.13 (L#11) | 0.05 (L#11) | |
| MLC Sag (mm) | Left | 0.62 | 0.82 (L#8) | 0.17 (L#3) |
| Right | 0.68 | 0.99 (L#8) | 0.15 (L#3) | |
| Gun | 0.34 | 0.57 (L#11) | 0.16 (L#6) | |
| Target | 0.32 | 0.61 (L#10) | 0.10 (L#3) |
Values are in mm except for the EPID tilt and skew which are given in degrees. The largest measured values are listed and their corresponding linac numbers are given in parentheses.