L-R (mm)

 

 

A-P (mm)

 

 

Unshifted

Shifted

Isocheck

Unshifted

Shifted

Isocheck

Mean

1.1

0.7

0.5

0.18

-0.12

-0.29

SD

3.8

3.8

3.6

6.1

4.4

3.4

Table 4: Comparison of mean and standard deviations of the displacements of the treatment isocenter from the planning position in the L-R and A-P directions for the ‘unshifted’, shifted and isochecks data sets.