Table 5 Summary of various published recommendations for margins around target volumes

Stroom et al. (1999a) [26]

2∑ + 0.7σ

95% absorbed dose to on average 99% of CTV tested in realistic plans.

Van Herk et al. (2000) [27]

2.5∑ + 0.7σ

Minimum absorbed dose to CTV is 95% for 90% of patients. Analytical solution for perfect conformation.

Parker et al. (2002) [28]

\( \sum +\sqrt{\left({\sigma}^2+{\sum}^2\right)} \)

95% minimum absorbed dose and 100% absorbed dose for 95% of volume. Probability levels not specified.

Snoke JJ (2007)

2.5∑ + β(σ ² + σ ² _P )^1/2 − βσ _P

Minimum 95% of the prescribed dose for 90% of patients