Table 3.
The minimum DV level that had a clinically significant impact on PPQM (defined by mean ΔPPQM values lower than that caused by a 2% output error, ΔPPQM(OP + 2%) = −2.7%) at each level of SV. Values in parentheses indicate the mean ΔPPQM for the indicated SV and DV levels. N/A indicates that even High DV did not produce a significant effect. Values in parentheses for these cases indicate the maximum absolute ΔPPQM from all DV levels.
| Minimum DV with clinically relevant average ΔPPQM | |||
|---|---|---|---|
| Dmean PQMs | Any OAR | Abutting target | Not abutting target |
| SV = 0 | High (−4.1%) | High (−6.8%) | N/A (max −1.6%) |
| SV = 2 mm | N/A (max −1.8%) | N/A (max −2.5%) | N/A (max −1.8%) |
| SV = 4 mm | N/A (max −0.2%) | N/A (max −1.1%) | N/A (max −2.3%) |
| SV = 10 mm | N/A (max 0.0%) | N/A (max −0.3%) | N/A (max −0.0%) |
| Dmax PQMs | Any OAR | Abutting target | Not abutting target |
| SV = 0 | Medium (−5.5%) | Low (−10.4%) | Medium (−3.1%) |
| SV = 2 mm | Medium (−2.8%) | Low (−6.2%) | High (−8.9%) |
| SV = 4 mm | High (−6.3%) | Low (−6.5%) | High (−5.1%) |
| SV = 10 mm | N/A (max −2.3%) | Low (−5.1%) | N/A (max −0.3%) |