2017_IGRT course book

Nomenclature

• Gross error: mistakes, transcription errors, software faults:

• must be caught by QA, not in this lecture

• Error: difference between planned measurand and its true value during treatment, however small

• Uncertainty: unpredictable errors– quantified by standard deviations

• Variation: predictable or periodic errors– quantified by amplitude or standard deviations