Health-related quality-of-life measurement in patients with Parkinson's disease

Outcome measures are increasingly used to assess the impact of diseases suc h as Parkinson's disease (PD) from the patient's perspective. These measure s, in the form of questionnaires to assess health-related quality of life ( HR-QOL), are of 2 main kinds: generic and disease-specific. The former is i ntended to be relevant to the widest range of health problems; the latter i s developed specifically to assess HR-QOL for a specific condition. Possibl e consequences of PD have been assessed by generic instruments such as the Sickness Impact Profile (SIP), the Nottingham Health Profile (NHP), the Med ical Outcomes Study 36-Item Short Form (SF-36) Health Survey and also by di sease-specific instruments; in particular, the Parkinson's Disease Quality- of-Life Questionnaire (PDQL) and 39-Item Parkinson's Disease Questionnaire (PDQ-39). This article summarises the criteria whereby such instruments sho uld be evaluated by potential users and describes in more detail the method s of developing and testing such disease-specific instruments for use in PD . There is a range of valid and feasible methods available for taking into account patients' views of PD outcomes. These will become important outcome measures in future clinical trials of treatment regimes.