Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor symptoms such as bradykinesia, rigidity, tremor and postural instability. Available therapy is symptomatic, although several approaches have been investigated as potential disease-modifying therapies. Clinical trial outcomes are typically measured by means of rating scales, of which the Unified PD Rating Scale (UPDRS) is the most commonly used, particularly part III, its motor examination section. Despite its central role, the UPDRS has not been examined regarding its role as a measurement instrument. This paper describes results from an analysis according to Rasch Measurement Theory (RMT) of 804 complete clinical UPDRS III assessments. Results show that the scale exhibits mistargeting, with the vast majority of people being located at the lower half (i.e., less severe symptoms) of its measurement range. Furthermore, evidence suggests multidimensionality as well as redundancy, and problems with the empirical functioning of rating scale categories. It is concluded that the UPDRS represents a clinical assessment tool rather than a measurement instrument, which may contribute to a range of missed opportunities regarding therapeutic developments as well as understanding of the disease itself. Potential remedies include separation into symptom specific scales and reconceptualization in order to expand its range of measurement.
|Status||Publicerad - 2017|
|Evenemang||The 5th International Outcome Measurement Conference. Chicago, Illinois, USA, 2017 - |
Varaktighet: 1980-jan-01 → …
|Konferens||The 5th International Outcome Measurement Conference. Chicago, Illinois, USA, 2017|
|Period||80-01-01 → …|
- Hälsovetenskap (303)
- Neurologi (30207)