1086 / 1674
CTV - PTV margin = 2.5 • Σ + 0.7 • σ
Σ: population systematic error
= SD of overall population mean setup error
σ: population random error
= average of SDs of individual daily random error
Margin calculation recipe
van Herk et al. IJROBP 47:1121-1135, 2000
-2,0
-1,5
-1,0
-0,5
0,0
0,5
1,0
1,5
2,0
-2,0
-1,5 -1,0
-0,5
0,0
0,5
1,0
1,5
2,0
mean setup error (systematic)
daily setup error (random
)
Measurements for many patients and many fractions