MDS-UPDRS

The research record

This is the project's file for this landmark, as written and checked. Sources are listed at the end; anything not yet confirmed is marked "Not yet verified".

Who

The MDS-UPDRS Task Force led by Christopher Goetz, with Barbara Tilley, Stephanie Shaftman, Glenn Stebbins, Stanley Fahn, Werner Poewe and many others, under the Movement Disorder Society, which sponsored the revision. PubMed lists US NIH extramural support for the validation paper; the exact grants were not checked.

What happened

The original UPDRS was first published in the 1980s (a 1987 paper by Fahn and Elton is cited in the later critique) and, after a 2003 critique by the Movement Disorder Society's own task force, was rewritten and expanded. That critique listed ambiguous wording, weak rater instructions and no screening of non-motor symptoms among the old scale's flaws. The new scale has four parts: I (non-motor experiences of daily living), II (motor experiences of daily living), III (clinician-rated motor examination) and IV (motor complications). Patients or caregivers answer 20 questions themselves. In the validation study, specialists scored 877 English-speaking patients at 39 sites on both the old scale (55 items) and the new one (65 items). Results correlated highly (0.96 as reported), internal consistency was good (0.79-0.93 across parts), and the authors recommended using each part's sum separately rather than one grand total (Movement Disorders 23:2129-2170, 15 Nov 2008).

Why it moved us toward a cure

A trial can only show slowing if it can measure progression. Because nearly every later study used the same scale, results could be compared and pooled: Part III (off medication) is the main measure in the exenatide Phase 2 (landmark 20) and in the GREAT ambroxol trial (landmark 40), and the combined Parts I-III score is the main measure in prasinezumab's PASADENA (landmark 63) and the ASPro-PD ambroxol Phase 3 (landmark 321). Newer biomarkers are tested against it, for example blood neurofilament light (landmark 115).

It replaced older global scales such as Hoehn and Yahr staging (landmark 284) for measuring change.

Outcome

Advanced. It remains the trial standard, but it is a clinician's rating, so it is subjective, shifts with medication state, and may miss slow change; this is the reason regulators and consortia are pursuing objective digital and biological measures (landmark 120, landmark 118). The ADAGIO delayed-start trial (landmark 62) used the original scale. No correction or retraction was found for the 2008 paper (Crossref, Europe PMC). The clinical-difference question has been studied: one study of 260 patients estimated thresholds for Part III (Horváth 2015); whether any regulator has endorsed one was not checked.

Sources

• Goetz et al., Mov Disord 2008;23(15):2129-2170, DOI 10.1002/mds.22340
• Movement Disorder Society Task Force, "The UPDRS: status and recommendations", Mov Disord 2003;18:738–750, DOI 10.1002/mds.10473
• Horváth et al., Parkinsonism Relat Disord 2015;21:1421–1426, DOI 10.1016/j.parkreldis.2015.10.006
• Trial use: see the linked landmark files above, which cite the individual trials.
• Not yet verified: the full list of Task Force members; the Fahn and Elton 1987 paper itself (known only from the critique's reference list); whether any minimal clinically important difference threshold is regulator-endorsed; the number of language translations.