A fractionation schedule of D Gy in n fractions (with d Gy per fraction) is equivalent to a BED of BED Gy₁₀ and EQD₂ of EQD2 Gy, assuming an α / β ratio of a/b.

RBApp stands for RadioBiology Application and is a web application. This web application allows quick access to radiobiological calculations, right on your mobile device.

Keep in mind that the results of calculations are for educational purposes only, and should not be used for clinical decision making.

To use this program, input numbers into two of three of the fields: Total dose, number of fractions, dose per fraction. The program will automatically calculate the third value.

A alpha/beta ratio is also required. Classically, a value of α / β = 10 is used for tumours and α / β = 3 for normal tissues.

If input values are invalid, an alert dialog box will display and the program will take users to a blank Results screen. Users need to click the top left "RBApp" button to return to the main screen to re-enter their values. (July 2012)

Clicking on an external link on iOS devices will lead users away from RBApp, and a user may need to click the Home button to return to the main screen. (July 2012)

RBApp
Copyright © Derek Tsang 2012-2015. All Rights Reserved.

The default mode allows you to calculate BED and EQD₂ from knowledge of the following parameters:

• two of three of the following variables:
• total dose (D)
• number of fractions (n)
• dose per fraction (d)
• α / β ratio

The advanced mode will allow you to calculate all values from knowledge of at least three of the following parameters:

• BED or EQD₂
• α / β ratio
• one of three of the following variables:
  • total dose (D)
  • number of fractions (n)
  • dose per fraction (d)

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.

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.

For more information, consult the following resources:

• 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)

This web application allows quick access to radiobiological calculations, right on your mobile device. Keep in mind, however, that the results of calculations are for educational purposes only, and should not be used for clinical decision making.

This web application does not provide medical advice, diagnosis, treatment or care. If you have a health problem, medical emergency, or a general health question, you should contact a physician or other qualified health care provider for consultation, diagnosis and/or treatment. Under no circumstances should you attempt self-diagnosis or treatment based on anything you have seen or read on this web application. Call 911 for all medical emergencies.