.. index:: 
   single: Parameters; 1D Deviation CAX

1D Deviation CAX
================

This is the maximum variation in the absorbed dose over the :ref:`in field area<In Field Area>` normalised to the central axis.

.. math:: 100 \cdot \cfrac {max - min} {cax}
   
Where *max*, *min* and *cax* are the profile maximum, minimum and central axis values respectively.

**Protocol invocation name**: 1D Deviation CAX


|Note| The *max*, *min* and *cax* are affected by :ref:`normalisation<Normalisation>` or windowing.

.. |Note| image:: _static/Note.png