Validation Study of the Official Korean Version of the Movement Disorder Society-Unified Parkinson's Disease Rating Scale

The Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) has been available in English since 2008. As part of this process, the MDS-UPDRS organizing team developed guidelines for development of official non-English translations. We present here the formal process for completing officially approved non-English versions of the MDS-UPDRS and specifically focus on the first of these versions in Italian. The MDS-UPDRS was translated into Italian and tested in 377 native-Italian speaking PD patients. Confirmatory and exploratory factor analyses determined whether the factor structure for the English-language MDS-UPDRS could be confirmed in data collected using the Italian translation. To be designated an 'Official MDS translation,' the Comparative Fit Index (CFI) had to be ≥0.90 relative to the English-language version. For all four parts of the Italian MDS-UPDRS, the CFI, in comparison with the English-language data, was ≥0.94. Exploratory factor analyses revealed some differences between the two datasets, however these differences were considered to be within an acceptable range. The Italian version of the MDS-UPDRS reaches the criterion to be designated as an Official Translation and is now available for use. This protocol will serve as outline for further validation of this in multiple languages.

Relationships among cognitive impairment, sleep, and fatigue in Parkinson's disease using the MDS-UPDRS.

We present a clinimetric assessment of the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS). The MDS-UDPRS Task Force revised and expanded the UPDRS using recommendations from a published critique. The MDS-UPDRS has four parts, namely, I: Non-motor Experiences of Daily Living; II: Motor Experiences of Daily Living; III: Motor Examination; IV: Motor Complications. Twenty questions are completed by the patient/caregiver. Item-specific instructions and an appendix of complementary additional scales are provided. Movement disorder specialists and study coordinators administered the UPDRS (55 items) and MDS-UPDRS (65 items) to 877 English speaking (78% non-Latino Caucasian) patients with Parkinson's disease from 39 sites. We compared the two scales using correlative techniques and factor analysis. The MDS-UPDRS showed high internal consistency (Cronbach's alpha = 0.79-0.93 across parts) and correlated with the original UPDRS (rho = 0.96). MDS-UPDRS across-part correlations ranged from 0.22 to 0.66. Reliable factor structures for each part were obtained (comparative fit index > 0.90 for each part), which support the use of sum scores for each part in preference to a total score of all parts. The combined clinimetric results of this study support the validity of the MDS-UPDRS for rating PD.

This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process.

Validation of the Hebrew version of the Movement Disorder Society—Unified Parkinson's Disease Rating Scale

Predicting initiation of dopaminergic therapy in early Parkinson's disease (PD) is important for clinical management and trial design. Prior cross-sectional work identified a six-item patient-reported subset from the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Parts IB + II, but its longitudinal utility is unknown. To test whether modeling longitudinal symptom trajectories improves prediction of dopaminergic therapy initiation beyond baseline-only models, and to identify an abbreviated patient-reported subset with stable prognostic value and utility for trial stratification. Data were harmonized from 1787 untreated early PD patients across six multicenter studies. All 20 MDS-UPDRS Parts IB + II items were analyzed using a longitudinal item response theory model. Items were ranked by discrimination and information functions, and cumulative subsets evaluated in Cox models with time-dependent covariates, adjusted for age, sex, disease duration, and Hoehn and Yahr stage. Predictive accuracy was quantified by concordance index (C-index) for full follow-up and truncation at 1 and 2 years. Risk stratification was assessed based on baseline abbreviated subset scores using Kaplan-Meier analyses. An 11-item model consistently outperformed the full 20-item scale (C-index 0.609 vs. 0.597, P < 0.001 with full follow-up; 0.621 vs. 0.599, P < 0.001 at 1 year; 0.615 vs. 0.602, P < 0.001 at 2 years). Longitudinal updates improved discrimination over baseline-only models (eg, 0.609 vs. 0.594 for full follow-up). Higher baseline 11-item scores were strongly associated with earlier therapy initiation. Longitudinal symptom modeling improves prediction of therapy initiation in early PD. An abbreviated 11-item patient-reported MDS-UPDRS provides stronger prognostic value than the full scale and supports trial stratification and clinical monitoring. © 2025 International Parkinson and Movement Disorder Society.

ABSTRACTBackgroundAlthough nontremor and tremor Part 3 Movement Disorder Society–Unified Parkinson's Disease Rating Scale items measure different impairment domains, their distinct progression and drug responsivity remain unstudied longitudinally. The total score may obscure important time‐based and treatment‐based changes occurring in the individual domains.ObjectiveUsing the unique advantages of item response theory (IRT), we developed novel longitudinal unidimensional and multidimensional models to investigate nontremor and tremor changes occurring in an interventional Parkinson's disease (PD) study.MethodWith unidimensional longitudinal IRT, we assessed the 33 Part 3 item data (22 nontremor and 10 tremor items) of 336 patients with early PD from the STEADY‐PD III (Safety, Tolerability, and Efficacy Assessment of Isradipine for PD, placebo vs. isradipine) study. With multidimensional longitudinal IRT, we assessed the progression rates over time and treatment (in overall motor severity, nontremor, and tremor domains) using Markov Chain Monte Carlo implemented in Stan.ResultsRegardless of treatment, patients showed significant but different time‐based deterioration rates for total motor, nontremor, and tremor scores. Isradipine was associated with additional significant deterioration over placebo in total score and nontremor scores, but not in tremor score. Further highlighting the 2 separate latent domains, nontremor and tremor severity changes were positively but weakly correlated (correlation coefficient, 0.108).ConclusionsLongitudinal IRT analysis is a novel statistical method highly applicable to PD clinical trials. It addresses limitations of traditional linear regression approaches and previous IRT investigations that either applied cross‐sectional IRT models to longitudinal data or failed to estimate all parameters simultaneously. It is particularly useful because it can separate nontremor and tremor changes both over time and in response to treatment interventions.

Original clinimetric analyses by the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) developers did not confirm the validity of summing the scores of its parts. Recent studies used the summed score of Part III and other parts as efficacy outcomes. The aim of this study was to establish whether summing scores of MDS-UPDRS parts can be recommended. Using 7466 full MDS-UPDRS scores, we applied two-step factor analysis as in the original article to reassess the validity analysis with the threshold criterion set at comparative fit index ≥0.9. All comparative fit indexes of any combination including Part III were lower than 0.90. Summing Part III MDS-UPDRS scores with other parts is not clinimetrically sound. The MDS-UPDRS is a validated four-part scale with corresponding individual part scores and needs to be used within the limits originally presented. © 2022 International Parkinson and Movement Disorder Society.

The purpose of this study was to conduct a preliminary psychometric evaluation of the speech item of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III. Twenty neurologists specializing in movement disorders evaluated the speech-unscripted and sentence reading-of people with Parkinson's disease (PD) on the MDS-UPDRS Part III. The concurrent validity of the speech item was evaluated by comparing the ratings to a previously collected estimate of the speakers' intelligibility during sentence reading. The reproducibility of the ratings was evaluated in terms of reliability (intra- and interrater) and agreement. MDS-UPDRS Part III speech ratings based on sentence reading were moderately and negatively correlated with previously collected estimates of intelligibility. No such relationship was found for MDS-UPDRS Part III speech ratings based on unscripted speech. Individual correlations for each rater ranged widely, with some showing weak, negligible, or positive relationships with intelligibility. Intrarater reliability was high, but interrater reliability was fair for both speech tasks. Movement disorders specialists agreed on MDS-UPDRS speech ratings, on average, less than 70% of the time. A critical communication outcome-intelligibility during unscripted speech-is not captured by MDS-UPDRS Part III speech ratings, suggesting weak concurrent validity of this widely used metric of speech function. The reproducibility of MDS-UPDRS Part III speech ratings across providers is fair. These speech ratings may be insufficient to assess the speech function of people with PD and identify those in need of speech services.

Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and Unified Dyskinesia Rating Scale (UDysRS) were developed as standard tools to rate Parkinson's disease (PD) and drug-induced dyskinesias of PD. As these scales have become widely used, there is a need for translation to non-English languages. Here we present the standardization for the Turkish translations. The scales were translated into Turkish and then back-translated to English. These back-translations were reviewed by the MDS team. After cognitive pretesting, movement disorder specialists from nine centers tested 352 patients for MDS-UPDRS, and 250 patients for UDysRS. Confirmatory factor analyses (CFAs) were used to determine if the factor structures for the reference standards could be confirmed in the Turkish data. The comparative fit indexes (CFIs) for the scales were required to be 0.90 or higher. Exploratory factor analyses (EFAs) were conducted to explore the underlying factor structure without the constraint of a pre-specified factor structure. For both scales, the CFIs were 0.94 or greater as compared to the reference standard factor structures. The factor structures were consistent with that of reference standards, although there were some differences in some areas as compared to the EFA of the reference standard dataset. This may be due to the inclusion of patients with different stages of PD and different cultural properties of raters and patients. These results demonstrate that the Turkish translations of MDS-UPDRS and UDysRS have adequate clinimetric properties. They are established as the official translations and can be reliably used in Turkish speaking populations.

Regulatory recommendations favor outcomes combining objective and patient input. The Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS), the most commonly used scale in Parkinson's disease (PD), includes patient and investigator ratings in distinct parts, but original clinimetric analyses failed to confirm the validity of combining parts by simple summing. The aim was to develop clinimetrically valid constructs for combining patient-reported Part 2 and investigator-rated Part 3 MDS-UPDRS scores. Using 7888 MDS-UPDRS scores, we assessed construct validity of combined Part 2 and Part 3 items using exploratory factor analysis (EFA) and graded item response theory (IRT) with threshold criteria: comparative fit index≥0.9 (EFA) and discrimination parameters≥0.65 (IRT). The direct sum of Parts 2+3 failed to meet the threshold for a valid outcome of PD severity (comparative fit index, CFI=0.855). However, a two-domain construct combining item scores for tremor and non-tremor domains from Parts 2 and 3 confirmed validity, meeting both EFA and IRT criteria as distinct but correlated indices of disease severity (CFI=0.923; discrimination mean 2.197 ± 0.480 [tremor] and 1.737 ± 0.344 [non-tremor] domains). The sum of Parts 2+3 is not clinimetrically sound. However, considering tremor and non-tremor items of both Parts 2 and 3 as two outcomes results in a valid summary of PD motor severity that leverages simultaneous patient- and investigator-derived measures. This analytic application addresses regulatory prioritizations and retains the well-validated MDS-UPDRS items. In future interventional trials, we suggest that tremor and non-tremor components of PD motor severity from Parts 2+3 be monitored and analyzed to accurately detect objective changes that integrate the patient's voice. © 2023 International Parkinson and Movement Disorder Society.

Non-motor symptoms (NMSs) negatively impact the health-related quality of life (HrQOL) of patients with Parkinson's disease (PD). The Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is a comprehensive scale for evaluating PD. It remains unclear whether the NMSs evaluated with MDS-UPDRS are predictive of HrQOL. This study aimed to investigate whether NMSs, as evaluated with the MDS-UPDRS, could predict the HrQOL of patients with PD. We conducted a 2-year retrospective observational cohort study assessing 108 patients with PD who were recruited from a single tertiary center between January 2015 and December 2017. MDS-UPDRS was used to assess NMSs and motor symptoms and Parkinson's Disease Questionnaire-39 (PDQ-39) to measure patients' HrQOL. The median age of patients was 69years, and 65.7% were female. The median MDS-UPDRS part I, part II, part III, and PDQ-39-summary index scores were 8, 10, 22, and 25, respectively. The final stepwise multiple linear regression model showed that female sex (standard partial regression coefficient β = 0.131, P < 0.05) and baseline MDS-UPDRS part I (β = 0.272, P < 0.01) and part II (β = 0.571, P < 0.01) scores significantly predicted the PDQ-39-SI scores at the 2-year follow-up. In addition to motor symptoms, NMSs at the 2-year follow-up may be useful for predicting the HrQOL of patients with PD. In clinical practice, MDS-UPDRS-guided assessment and treatment of motor symptoms and NMSs may contribute to improving HrQOL in patients with PD.

The Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III is widely used to examine the overall motor severity of patients with Parkinson's disease (PD). However, manual implementation of the MDS-UPDRS scheme for PD diagnosis demands substantial time and effort, which imposes physical and cognitive burdens on both patients and neurologists during PD examinations. To tackle this challenge, this study proposes an explainable machine learning approach to automate PD diagnosis by predicting the total MDS-UPDRS Part III score based on a patient's kinematic data during gait. First, MDS-UPDRS Part III examinations for 30 patients with early PD symptoms were performed by a neurologist. Next, gait experiments using a motion capture system were conducted to obtain the ankle, knee, and hip joint angles of the patients at each gait cycle. The collected joint angle data were transformed into joint angle matrices for gait cycles to represent gait pattern images in lower extremities. Then, a two-dimensional convolutional neural network (2D-CNN) model was trained using the gait pattern image to estimate the total MDS-UPDRS Part III score. In addition, the gradient-weighted class activation mapping (Grad-CAM) method was employed to extract plausible gait characteristics for the obtained MDS-UPDRS score. The proposed approach not only suitably predicts the total MDS-UPDRS Part III score but also reveals that significant features for predicting the MDS-UPDRS score are linked to both the single leg support phase and the swing phase of Parkinsonian gait.

ABSTRACTAlthough gait and balance difficulties often occur together in Parkinson's disease (PD) patients, it is believed that they are actually two separate symptoms. However, there are no simple tests to distinguish them. We have developed the self-administered Barrow Neurological Institute (BNI) question to distinguish between gait and balance issues in PD and it was tested in 102 consecutive PD patients. The responses were compared with those of the walking and balance question (item # 2.12) of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS), and the MDS-UPDRS motor examination and its subsets such as gait and postural stability (PS). Fifty-five patients reported balance difficulty on the BNI question and 64 reported walking and balance difficulty on the MDS-UPDRS question. Of the patients who reported balance difficulty on the BNI question, 74.5% had a PS score ≥2 and 25.4% fell at least three times per month. Of the patients who reported walking and balance difficulty on the MDS-UPDRS question, only 59.4% had a PS score ≥2 and only 10.9% fell three or more times per month. These statistically significant results suggest that the BNI question is better able to detect balance difficulty and its associated falls in PD and can be a supplement to the MDS-UPDRS or a stand-alone question to evaluate balance difficulty and its associated falls in PD.

Efecto del entrenamiento resistido sobre el equilibrio y control postural en personas con párkinson: una revisión sistemática