BED equation

EQD2 Equation

BED = biologically effective dose
EQD2 = dose in 2 Gy fractions biologically equivalent to dose D given in fractions of size d, in units of Gray

E is biological effect, D is total dose (D = nd), d is dose per fraction, n is the number of fractions, and alpha/beta is a property of the irradiated tissue.

For more information:
Jones et al., The role of biologically effective dose (BED) in clinical oncology, Clinical Oncology, 13(2), 2001, 71-81
Radiobiology for the Radiologist - Hall & Giaccia, 7th edition (ISBN-13 978-1608311934)
Basic Clinical Radiobiology - Van der Kogel & Joiner, 4th edition (ISBN-13 978-0340929667)

BED equation is based on Hall and Giaccia, Radiobiology for the Radiologist, 2012, Lippincott Williams & Wilkins. EQD2 equation is based on Joiner and van der Kogel, Basic Clinical Radiobiology, 2009, Hodder Education.

This page is part of RBApp, an online radiobiology calculator.