The Validity of Health-Related Quality of Life Instruments in Patients With Late-Stage Parkinson's Disease.

Objective: To examine the validity of health-related quality of life (Hr-QoL) measures in patients with late-stage Parkinson's disease (PD).

Methods: We analysed data from patients with late-stage PD and their carers who were assessed with a range of clinical measures and the EQ-5D-3 L. The DEMQOL-Proxy was completed for 157 patients with a diagnosis of dementia and the PDQ-8 by 401 patients without dementia.