Dose Course 2018_Flipping book

Tolerance limits and action levels

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“The overall accuracy of entrance in vivo measurements is determined by the combined uncertainty in the calibration factor, the correction factors and the accuracy and reproducibility in diode position ” In our case it is equal to 2% (1sd ). So without any additional cause of error 68% of all measurements would have a dispersion of ± 2% and 95% of ± 4%.”

Essers and Mijnheer, Int.J.Radiat.Oncol.Biol.Phys., 1999