Are the MDS-UPDRS-Based Composite Scores Clinically Applicable?

Abstract

Background: The International Parkinson and Movement Disorder Society-sponsored UPDRS (MDS-UPDRS) is a powerful clinical outcome measure.

Objectives: To evaluate the feasibility of various MDS-UPDRS-based composite scores and determine their minimal clinically important difference threshold values.

Methods: Overall, 1,113 paired investigations of 452 patients were reviewed implementing three different techniques simultaneously.

Results: Based on the ordinal regression modeling, the MDS-UPDRS II+III, MDS-UPDRS I+II+III, and the total score of MDS-UPDRS are clinically applicable outcome measures. Any improvement greater than 4.9 points or any worsening more than 4.2 points on MDS-UPDRS II+III represent a minimal, yet clinically meaningful, change. In reference to MDS-UPDRS I+II+III, the smallest changes considered clinically relevant were 6.7 and 5.2 points for improvement and deterioration, respectively. The thresholds for the total score of MDS-UPDRS were 7.1 points for improvement and 6.3 points for worsening.

Conclusions: Our findings support the application of various MDS-UPDRS-based composite scores. © 2018 International Parkinson and Movement Disorder Society.

Keywords: UPDRS; minimal but clinically relevant differences; minimal clinically important changes; patient-reported outcomes; receiver operating characteristic curve.