ABSTRACT
Modelling assessments are already invaluable in special circumstances, e.g. treatment delivery errors (under-dosage or over-dosage) or if treatment is unintentionally interrupted, be this during external fractionated radiotherapy or brachytherapy. Where higher than usual doses of radiation are used, any local dose variations assume increased significance and modelling offers a valuable aid in the assessment of the resultant biological effect. Also, in the reporting of clinical data that comprise multiple different fractionation schedules, the quantification of the expected biological effect provides a method for inter-patient and inter-departmental comparisons.
