Health-related quality of life evaluation by proxy in Parkinson's disease: approach using PDQ-8 and EuroQoL-5D.

Patient- and caregiver-based scores were compared and agreement levels ascertained to determine the reliability of proxy evaluation of Parkinson's Disease (PD) patients' health-related quality of life (HRQoL) using the EuroQoL and PD questionnaire (PDQ)-8. Of 72 patient-caregiver pairs, 64 (88.88%) returned the questionnaires. The degree of agreement varied for individual dimensions. Proxy evaluation of PD patients' HRQoL showed limitations mainly with assessments using the EuroQoL and especially in patients with severe disease and depression.