Inclusion Criteria:  A diagnosis of head and neck cancer (any stage) Age 18 years or greater Receiving radiation therapy to the head and neck with a thermoplastic immobilisation mask An ECOG score in the range of 0 to 2 Any other prior or concurrent therapy allowed  Exclusion Criteria:  People with cognitive impairment which would preclude them from providing informed consent People who are unable to speak and read English and for whom obtaining consent would be difficult.