The SCOPA-Motor Scale for assessment of Parkinson's disease is a consistent and valid measure

The SCOPA-Motor Scale (S-MS) for assessment of Parkinson's disease (PD), contains 21 items in three domains: Motor examination, Disability, and Complications. Our objective was to validate the S-MS Spanish version.

This validation study was based on a multicenter, cross-sectional, one-point-in-time evaluation design. The applied measures were: Unified Parkinson's Disease Rating Scale-3.0 (UPDRS); S-MS; PD Global Evaluation (PDGE); and Clinical Global Impression of severity (CGI). Completeness of data collection, floor and ceiling effect, internal consistency, precision, and construct and discriminative validity were analyzed in 151 PD patients.

Scores from S-MS were fully computable. Floor effect was high for Complications (43.7%). Cronbach's alpha was > 0.90 for every domain, and item-total correlation was > 0.70 except for Examination. Standard error of measurement (SEM) ranged from 0.40 to 2.4. Convergent validity with corresponding UPDRS sections yielded coefficients > 0.90. Discriminative validity across Hoehn and Yahr (HY) and CGI stages was significant (Kruskal-Wallis, P < .0001). Insofar as internal consistency was concerned, alpha-values of the Examination sections were marginally higher for the UPDRS than for the S-MS (a finding perhaps accounted for by redundancy in this part of the UPDRS).

The S-MS is a consistent and valid scale, shorter by almost half than the UPDRS.