The Clinically Important Difference on the Unified Parkinson's Disease Rating Scale

Abstract

Concordance among multiple approaches of analysis based on subjective and objective data show that reasonable estimates for the CID on the UPDRS motor score are 2.5 points for minimal, 5.2 for moderate, and 10.8 for large CIDs. Estimates for the UPDRS total score are 4.3 points for minimal, 9.1 for moderate, and 17.1 for large CIDs. These estimates will assist in determining clinically meaningful changes in PD progression and response to therapeutic interventions.