Background Prion diseases, also known as transmissible spongiform encephalopathies (TSE's) are a group of progressive neurodegenerative conditions for which there is no current treatment or cure. Human prion diseases include sporadic CJD, variant CJD and inherited prion disease. The National Prion Clinic (NPC) is the national referral centre for prion disease. The NPC provides diagnosis and care for all forms of prion disease and also plays a key role in facilitating research to promote early diagnosis and the development of potential therapies. Currently the NPC run the National Prion Monitoring Cohort, an observational study which aims to build up a detailed understanding of the complex symptoms of prion disease and establish which tests most accurately measure disease progression. A symptomatic measurement tool has been developed to assist with monitoring patients' condition.

Aim 1) Establish the face validity of the symptomatic measurement tool. 2) Explore carer experience of caring for someone with prion disease.

Method Twenty family members of people with prion disease who had the role of main carer for the duration of their illness were selected. The sample included carers of deceased patients and those currently caring. Each carer was interviewed for up to 2 h. Interviews were recorded. Carers were asked to describe each symptom as it presented from the onset of illness to the present day. Carers were encouraged to describe the impact each symptom had on their relationship with the patient and wider family relationships.

Results The project is on-going. Early interviews suggest that symptoms such as personality and behaviour change, and mood disturbance are difficult to capture and score quantitatively, yet these are the problems which affect carers, and in turn patients the most. These symptoms are most likely to lead to carer burn out and breakdown of care package and therefore require careful monitoring.