Figure 2. Comparison of (A) MU/CP, (B) area aperture (AA)/CP, (C) MU×AA/CP as a function of gantry angle in three institutions. The vertical axis represents the MU and the horizontal axis represents the gantry angle. MU, AA, or MU×AA of each CP averaged across 45 plans was plotted for each institution. Error bars represent the standard error. MU: Monitor unit; CP: control point; AA: aperture area.
