Minimal clinically important change in patients with cervical dystonia: Results from the CD PROBE study

Abstract

Objective: To determine the minimal clinically important change (MCIC) on Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores using data from Cervical Dystonia Patient Registry for Observation of OnabotulinumtoxinA Efficacy (CD PROBE), which captured real-world practices and outcomes. Methods: Changes in the baseline TWSTRS scores (point and percentage changes) were compared to changes in the Patient and Clinician Global Impression of Change (PGIC and CGIC) ratings. Using logistic regression, the discrimination of the model was determined. Results: Among the 479 patients who completed all TWSTRS assessments, the mean TWSTRS Total score significantly decreased from baseline (39.2) to the final visit (27.1) (P