Comparative performance of prescription protocols
| Protocol | R | Accuracy | Precision | ||||
|---|---|---|---|---|---|---|---|
| Mean | SD | N | Mean | SD | N | ||
| A. Full Data Seta | |||||||
| AX + 15 | 9.36° | 7.38° | 200 | 7.53° | 5.11° | 100 | |
| OML* | 0.78 | 5.73°* | 4.56° | 100 | 6.67° | 5.34° | 50 |
| HP + 12 | 0.82 | 5.98°* | 5.73° | 100 | 5.32°* | 4.38° | 50 |
| B. Reduced Data Set (Excessive Head Extension Controlled)b | |||||||
| AX + 15 | 7.18° | 6.78° | 147 | 7.34° | 5.38° | 66 | |
| OML* | 0.69 | 4.87°* | 3.99° | 78 | 6.77° | 5.97° | 35 |
| HP + 12 | 0.87† | 3.27°*,† | 2.87° | 69 | 4.37°*,† | 3.79° | 31 |
Note.—R, Pearson’s correlation coefficient; SD, standard deviation.
a Results for the full data set.
b Results controlled for head extension requiring gantry tilt prescription greater than 22°.
* , Significant improvement (P < .05) versus AX + 15 protocol.
† Significant improvement (P < .05) versus OML* protocol.