Tools to assess the quality of life in patients with Parkinson's disease: a systematic review.

INTRODUCTION: The clinical, social, and economic implications of Parkinson's disease (PD) are significant; disability occurs leading to a low quality of life (QoL). Information on the QoL of patients with PD and studies on the relationship between QoL and motor and cognitive function are necessary for both research and clinical use to make informed decisions in healthcare and rehabilitation. The aim of this study was to determine which scales are most used to assess QoL in patients with PD. AREA COVERED: A literature search was conducted in MEDLINE, Scopus, CINAHL, PsycINFO, and Web of Science. Two authors independently identified eligible studies based on predefined inclusion criteria and extracted the data. Study quality and the risk of bias were assessed using the COSMIN checklist. EXPERT OPINION: 116 suitable studies were included, and 42 different instruments were identified. The most frequently used scales were the 39-items and 8-items Parkinson's Disease Questionnaire (PDQ-39) (PDQ-8). These findings suggest further investigation of existing PD outcome measures would benefit patients, researchers, and clinicians. Validated, universal outcome measures are required to allow comparisons across practice; therefore, we recommend that future researchers use a common set of outcome assessments based on the results of this review.