The UPDRS-8: a brief clinical assessment scale for Parkinson's disease.

We evaluated a brief, 8-item version of the Unified Parkinson's Disease Rating Scale (UPDRS) using two existing patient databases. One database included 1,445 PD patients. Spearman correlation between UPDRS-8 motor scores and full UPDRS motor scores was .765 (p < .001). Correlation between total UPDRS-8 scores and full UPDRS total scores (parts I-III) was .798 (p < .001). Correlation between total UPDRS-8 scores and total 39-item PD questionnaire (PDQ-39) scores was .629 (p < .001). In 177 patients undergoing deep brain stimulation (DBS), UPDRS-8 motor scores were similarly significantly sensitive to change as full UPDRS motor scores in assessing change from the medication OFF state to the medication ON state at baseline and from the medication OFF state at baseline to the medication OFF/stimulation ON state 1 year post-DBS. The UPDRS-8 focuses on items that are most relevant for clinical decision making. In this study, the UPDRS-8 exhibited good correlation with the full UPDRS and the PDQ-39. We therefore believe that it can provide a useful, rapid assessment of PD patients in clinical practice. Whether it might be useful in clinical trials depends on demonstrating that it is also sensitive to relatively small changes in clinical status.