Fig. 2
From: To propose adding index of achievement (IOA) to IMRT QA process
Examples of normalized dose difference for one of the head and neck cases when intentional spatial displacements are applied, from 1 to 3 mm along (a - c) horizontal or (d – f) longitudinal direction, respectively. All values were normalized to the maximum dose difference among the same group [i.e., (a – c) horizontal group or (d – f) longitudinal group]