Framebased-Frameless_DV_2017_final.pptx

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Random Error and Minimum Dose Requirement
▪ The margin for random decreases with decreasing prescription isodose line /
minimum dose requirement
95%
50%
73% M = bs2sp
2 - bsp
Prescription level b
95% 1.64
80% 0.84
70% 0.52
60% 0.25