Abstract
Background
The Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson’s Disease (PD) Rating Scale (UPDRS) (MDS-UPDRS) has been developed and is now available in English. Part of the overall program includes the establishment of official non-English translations of the MDS-UPDRS. We present the process for completing the official Japanese translation of the MDS-UPDRS with clinimetric testing results.
Methods
In this trial, the MDS-UPDRS was translated into Japanese, underwent cognitive pre-testing, and the translation was modified after taking the results into account. The final translation was approved as Official Working Draft of the MDS-UPDRS Japanese version and tested in 365 native-Japanese-speaking patients with PD. Confirmatory analyses were used to determine whether the factor structure for the English-language MDS-UPDRS could be confirmed in data collected using the Official Working Draft of the Japanese translation. As a secondary analysis, we used exploratory factor analyses to examine the underlying factor structure without the constraint of a pre-specified factor organization.
Results
Confirmatory factor analysis revealed that Comparative Fit Index for all Parts of the MDS-UPDRS exceeded the minimal standard of 0.90 relative to the English version and therefore Japanese translation met the pre-specified criterion to be designated called an OFFICIAL MDS TRANSLATION. Secondary analyses revealed some differences between the English-language MDS-UPDRS and the Japanese translation, however, these differences were considered to be within an acceptable range.
Conclusions
The Japanese version of the MDS-UPDRS met the criterion as an Official MDS Translation and is now available for use (www.movementdisorders.org).
Keywords: Parkinson’s disease, MDS-UPDRS, UPDRS, Rating scale, validation
Introduction
The Unified Parkinson’s Disease Rating Scale (UPDRS) has been widely used since the 1980’s as a standard clinical rating scale for Parkinson’s disease (PD). 1, 2 However, increasing evidence indicates that several symptoms frequently experienced by PD patients that affect their quality of life such as sleep problems, sensory disturbance, urinary problems, constipation and fatigue are not adequately evaluated in the original UPDRS.3 In 2001, the Movement Disorder Society (MDS) sponsored a critique of the UPDRS, and subsequently developed a new version of the scale termed the MDS-sponsored UPDRS revision. This new version, the MDS-UPDRS, was intended to be less ambiguous than its predecessor, and to incorporate a number of clinically pertinent PD-related problems poorly captured in the original version.4 In 2008, the MDS-UPDRS successfully passed clinimetric testing with high internal consistency and reliable factor structures for each part of the scale. 4 The new MDS-UPDRS comprises four parts: Part I evaluates non-motor experiences of daily living, Part II evaluates motor experiences of daily living, Part III evaluates motor function, and Part IV evaluates motor fluctuations and dyskinesia.
After the publication of the MDS-UPDRS, the MDS set forth a specific program to designate successful translations of non-English-language versions as official MDS translations. For this purpose, the MDS has set a strict protocol and criteria for testing. As of now, several official translations (Italian,5 Spanish,6 French, Estonian, German, Slovakian) have already been established and several other language programs are in progress. Herein, we present the scale translation and clinimetric testing results of the Japanese version of the MDS-UPDRS.
Patients and Methods
Translation of the MDS-UPDRS
The MDS-UPDRS was translated into Japanese by a team of natural Japanese speakers fluent in English who belong to the Department of Neurology of Wakayama Medical University in Japan, led by Kondo. The resultant Japanese translation was further reviewed by a team led by Mizuno from the Movement Disorder Society of Japan (MDSJ) to establish the original Japanese translation of the MDS-UPDRS. The translation was then back-translated by a team of colleagues fluent in English and Japanese who had not been involved in the original forward translation. The back-translation was reviewed by the administrative team in charge of the overall translation program (Stebbins, Goetz, LaPelle, Tilley).
Cognitive Pretesting
Cognitive pretesting is a qualitative approach to assess instrument completion in terms of task difficulty for examiner and respondent, and respondent interest, attention span, discomfort, and comprehension.7 Where there were observed differences between the back-translated Japanese version and the English version, items were selected for cognitive pretesting, along with questions that had been identified during cognitive pretesting of the English version. Cognitive pretesting was performed on the following sections: Part I Hallucinations and Psychosis; Features of Dopamine Dysregulation Syndrome; and Urinary Problems; Part II Freezing; Part III Postural Stability; and Rest Tremor Amplitude; Part IV Time Spent with Dyskinesia; and Functional Impact of Dyskinesia. Three-experienced Japanese movement-disorder specialists not involved in the original translation performed cognitive pretesting. Based on the results of the initial cognitive pretesting, additional round(s) of translation, back-translation, and cognitive pretesting could be required. After taking the cognitive pretesting results into account, the final Japanese translation was obtained.
Testing of the Japanese Version of the MDS-UPDRS
A total of 30-experienced Japanese movement-disorder specialists were recruited as members of the MDS-UPDRS Japanese version validation team led by Kashihara (members are listed in Table 1) to examine native-Japanese-speaking PD patients who had provided informed consent. The sample size for the translation study was based on the need for 5 participants per questionnaire item in order to perform the statistical analysis.8 There are 65 items on the MDS-UPDRS: thus a sample of at least 325 was required. Any participants with missing values within a part were excluded from the analysis of that part only. Hence, the sample size could vary by part. The investigators obtained approval to collect the data in accordance with relevant institutional ethics policies regarding human subjects. Anonymized patient data were transferred to the analysis team via a secure website. The protocol for the validation of the MDS-UPDRS Japanese version was approved by the ethics committees of each institute. Informed consent was obtained from all participants prior to the study.
Table 1.
The MDS-UPDRS Japanese Validation Study Group
| Investigators | Affiliation |
|---|---|
| Takashi Abe, M.D. | Department of Neurology, Abe Neurological Clinic |
| Kenichi Fujimoto, M.D. | Department of Neurology, Jichi Medical University Hospital |
| Kazuko Hasegawa, M.D. | Department of Neurology, National Sagamihara Hospital |
| Nobutaka Hattori, M.D. | Department of Neurology, Juntendo University School of Medicine |
| Yasuto Higashi, M.D. | Department of Neurology, Himeji Central Hospital |
| Takaki Imamura, M.D. | Department of Neurology, Okayama Kyokuto Hospital |
| Hidehumi Ito, M.D. | Department of Neurology, Wakayama Medical University |
| Kazunori Ito, M.D. | Department of Neurology, Iwamizawa Neurological 3 Medical Clinic |
| Kenichi Kashihara, M.D. | Department of Neurology, Okayama Kyokuto Hospital |
| Jyunya Kawada, M.D. | Department of Neurology, Shonan Kamakura General Hospital |
| Noriko Kawashima, M.D. | Department of Neurology, Kawashima Neurology Clinic |
| Seiji Kikuchi, M.D. | National Hospital Organization Hokkaido Medical Center |
| Sadako Kuno, M.D. | Kyoto Shijyo Hospital |
| Tetsuya Maeda, M.D. | Department of Neurology, Research Institute for Brain and Blood Vessels-Akita |
| Hideki Mochizuki, M.D. | Department of Neurology, Osaka University Graduate School of Medicine |
| Hideo Mori, M.D. | Department of Neurology, Juntendo University Koshigaya Hospital |
| Kenya Murata, M.D. | Department of neurology, Wakayama Medical University |
| Miho Murata, M.D. | Department of Neurology, National Center of Neurology and Psychiatry Parkinson Disease and Movement Disorder Center |
| Masahiro Nomoto, M.D. | Department of Neurology and Clinical Pharmacology Ehime University Graduate School of Medicine |
| Yasuyuki Okuma, M.D. | Juntendo University Shizuoka Hospital |
| Hidemoto Saiki, M.D. | Department of Neurology, Kitano Hospital |
| Hideyuki Sawada, M.D. | National Hospital Organization Utano Hospital |
| Ryosuke Takahashi | Department of Neurology, Graduate School of Medicine, Kyoto University |
| Atsushi Takeda | Department of Neurology, Tohoku University Medical School |
| Asako Takei | Department of Neurology, Hokuyukai Neurological Hospital |
| YasuoTerayama | Department of Neurology, Iwate Medical University |
| Masahiko Tomiyama | Department of Neurology, Aomori Prefectural Central Hospital |
| Yoshio Tsuboi | Department of Neurology Fukuoka University Medical School |
| Yoshikazu Ugawa | Department of Neurology, Fukushima Medical University |
| Mitsutoshi Yamamoto | Takamatsu Neurology Clinic |
| FusakoYokochi | Department of Neurology, Tokyo Metropolitan Neurological Hospital |
| Kazuto Yoshida | Department of Neurology, Japanese Red Cross Asahikawa Hospital |
| Fumihito Yoshii | Department of Neurology, Tokai University School of Medicine |
Investigators involved in the cognitive pretesting and/or vatidation and their affiliations. Investigators are listed in alphabetical order.
Data Analysis
Factor Analysis
M-plus, Version 6.119 was used to perform confirmatory and exploratory factor analyses (EFA), as the variables are categorical. We used a weighted least squares with mean- and variance-adjusted weighted least square (WLSMV) approach to factor estimation that minimizes the sum of squared differences between observed and estimated correlation matrices not counting diagonal elements. To assist in interpretation of the factors we used an orthogonal CF-VARIMAX rotation that constrains the factors to be uncorrelated. These methods were chosen to follow those used in the original examination of the English MDS-UPDRS.4
Primary Analysis
We conducted a confirmatory factor analysis (CFA) 10 as the primary analysis of the Japanese data to determine whether the factor structure for the English-language MDS-UPDRS4 could be confirmed in data collected by using the Japanese translation. This was the primary question of interest. The CFA was conducted separately for the MDS-UPDRS Parts I–IV, with the Japanese data constrained to fall into the factors defined in the English-language data.4 We evaluated the CFA results based on the Comparative Fit Index (CFI). According to protocol, to establish a successful translation and earn the designation of “official MDS-UPDRS translation,” the CFI for each Part (I–IV) of the translated instrument must be 0.90 or greater relative to the English-language version.4 Root Mean Square Error of Approximation (REMSA) was also calculated as another test of model fit. REMSA values < 0.05 were considered to be good fit and REMSA values of 0.1 or more were considered to be poor fit. WLSMV estimators were used to confirm model fit.
Secondary Analysis
As a secondary analysis we conducted an exploratory factor analysis11 for Parts I–IV of the Japanese version of the MDS-UPDRS to explore the underlying factor structure without the constraints of a pre-specified factor structure. We used a SCREE plot to choose the number of factors to retain for each part. The subjective SCREE test12 is scatter plot of eigenvalues plotted against their ranks with respect to magnitude, to extract as many factors as there are eigenvalues that fall before the last large drop (i.e., an “elbow” shape) in the plot. Once the factors were chosen, an item was retained in a factor if the factor loading for the item was 0.40 or greater.
The default estimator for factor analysis in M-plus is unweighted least-squares (ULS). When ULS converges, it yields more accurate parameter estimates and standard errors than does WLSMV. However, WLSMV generally outperforms ULS in convergence rates. Thus, Forero et al.13 suggest the use of ULS. In the case of nonconvergence, however, they suggest using WLSMV, as this method might converge when ULS does not. In this case, while the ULS algorithm did converge, it converged to an incorrect value, (i.e., a percent of variance explained that was greater than 1.0) so WLSMV was used.
The Chi-square test was used to analyze, additionally, the differences in the distribution of responses for each item of the MDS-UPDRS between PD patients of Japanese and English groups.
Results
Cognitive Pretesting
A total of 12 patients with Parkinson’s disease and their examiners were interviewed using a structured interview format typical in cognitive pretesting. During the first round of cognitive pretesting, minor word changes were suggested for Features of Dopamine Dysregulation Syndrome, Urinary Problems, and Time Spent with Dyskinesia. In response to comments from patients and caregivers, we enlarged the size of characters used in questions from Part IB and Part II. No items were identified as problematic during a second round of cognitive pretesting conducted with 10 patients with PD. The modified version of the scale was approved as the Official Working Draft of the Japanese MDS-UPDRS for testing in a larger group of patients with PD.
Data analysis
Demographics
Participants’ demographic characteristics are shown in Table 2. The Japanese dataset included 365 native-Japanese-speaking patients with PD who were examined using the MDS-UPDRS. In the Japanese sample, there was a greater proportion of female patient compared to the English sample. The two cohorts were similar on age, duration of disease but the distribution of Hoehn and Yahr stages were significantly different between the two cohorts (p < 0.0005) (Table 2).
Table 2.
Demographics of Japanese patients with Parkinson’s disease in comparison with the MDS-UPDRS (English version) data
| English | Japanese | p | |
|---|---|---|---|
| Total N | 876 | 365 | ns |
| % Male | 63.2 | 45.2 | <0.0005 |
| Age (mean± sd) | 68.2 (10.8) | 69.0 (9.2) | ns |
| Disease Duration (mean years ± sd) | 8.3 (6.7) | 7.8 (6.1) | ns |
| Years of Education | NA | 12.6 (2.7) | ns |
| Hoehn and Yahr Stage | <0.0005 | ||
| 0 | 0 | 2 | |
| 1 | 63 | 28 | |
| 2 | 467 | 164 | |
| 3 | 174 | 116 | |
| 4 | 109 | 42 | |
| 5 | 53 | 11 |
Primary analysis – confirmatory factor analysis
Table 4 displays the CFA models for each part of the MDS-UPDRS. For all four parts of the Japanese version, the CFI was 0.93 or greater in comparison with the English-language factor structure. Our pre-specified criterion was a CFI of 0.90 or greater; thus, we conclude that the English factor structure was confirmed in the Japanese dataset.
Table 4.
Confirmatory factor analysis model fit*
| Part I: Non-Motor Aspects of Experiences of Daily Living (a 2-factor model)** | |
| Japanese | CFI = 0.93, RMSEA = 0.09 (351 patients) |
| English-language | CFI = 0.97, RMSEA = 0.05 (849 patients) |
|
| |
| Part II: Motor Aspects of Experiences of Daily Living (a 3-factor model) | |
| Japanese | CFI = 0.99, RMSEA = 0.07 (356 patients) |
| English-language | CFI = 0.99, RMSEA = 0.05 (851 patients) |
|
| |
| Part III: Motor Examination (a 7-factor model) | |
| Japanese | CFI = 0.94, RMSEA = 0.08 (336 patients) |
| English-language | CFI = 0.95, RMSEA = 0.08 (801 patients) |
|
| |
| Part IV: Motor Complications (a 2-factor model) | |
| Japanese | CFI = 1.00, RMSEA = 0.06 (350 patients) |
| English-language | CFI = 1.00, RMSEA = 0.00 (848 patients) |
CFI: comparative fit index; RMSEA: root mean square error of approximation
Dopamine Dysregulation Syndrome was not included in this analysis as it did not load on any factor in the US version.
Secondary analysis – exploratory factor analysis
The factor structure of the EFA for the English version has been used as the basis for all confirmatory factor analyses, but our EFA of the Japanese dataset differs from that of the English-language dataset in some aspects. The results of the EFA for the English and Japanese versions are shown in Table 5; include the number of factors and their associated eigenvalues and percent variance.
Table 5.
Comparison of English-Language and Japanese Exploratory Factor Structures for Parts I–IV of the MDS-UPDRS
| Part I
| ||||
|---|---|---|---|---|
| English | Japanese | |||
|
| ||||
| Factor | Eigenvalues | Percent Variance | Eigenvalues | Percent Variance |
| 1 | 4.421 | 34.0 | 5.045 | 42.0 |
| 2 | 1.231** | 9.5 | 1.244 | 10.4 |
|
| ||||
| 3 | 1.051 | 8.1 | 1.081 | 9.0 |
| 4 | 1.007 | 7.7 | 0.866 | 7.2 |
| 5 | 0.811 | 6.2 | 0.721 | 6.0 |
| 6 | 0.724 | 5.6 | 0.642 | 5.4 |
| 7 | 0.673 | 5.2 | 0.594 | 5.0 |
| 8 | 0.630 | 4.8 | 0.508 | 4.2 |
| 9 | 0.616 | 4.7 | 0.472 | 3.9 |
| 10 | 0.542 | 4.2 | 0.375 | 3.1 |
| 11 | 0.519 | 4.0 | 0.288 | 2.4 |
| 12 | 0.399 | 3.1 | 0.160 | 1.3 |
| 13 | 0.376 | 2.9 | ||
| Part II
| ||||
|---|---|---|---|---|
| English | Japanese | |||
|
| ||||
| Factor | Eigenvalues | Percent Variance | Eigenvalues | Percent Variance |
| 1 | 6.898 | 53.1 | 7.293 | 56.1 |
| 2 | 1.128 | 8.7 | 1.062 | 8.2 |
| 3 | 1.000 | 7.7 | 0.826 | 6.4 |
|
| ||||
| 4 | 0.728 | 5.6 | 0.684 | 5.3 |
| 5 | 0.595 | 4.6 | 0.534 | 4.1 |
| 6 | 0.542 | 4.2 | 0.494 | 3.8 |
| 7 | 0.425 | 3.3 | 0.445 | 3.4 |
| 8 | 0.390 | 3.0 | 0.431 | 3.3 |
| 9 | 0.380 | 2.9 | 0.370 | 2.8 |
| 10 | 0.294 | 2.3 | 0.260 | 2.0 |
| 11 | 0.245 | 1.9 | 0.240 | 1.8 |
| 12 | 0.198 | 1.5 | 0.219 | 1.7 |
| 13 | 0.178 | 1.4 | 0.141 | 1.1 |
| Part III
| ||||
|---|---|---|---|---|
| English | Japanese | |||
|
| ||||
| Factor | Eigenvalues | Percent Variance | Eigenvalues | Percent Variance |
| 1 | 12.112 | 36.7 | 14.451 | 43.8 |
| 2 | 5.035 | 15.3 | 4.190 | 12.7 |
| 3 | 2.173 | 6.6 | 2.429 | 7.4 |
| 4 | 2.051 | 6.2 | 1.961 | 5.9 |
| 5 | 1.615 | 4.9 | 1.668 | 5.1 |
| 6 | 1.485 | 4.5 | 1.238 | 3.8 |
| 7 | 1.104 | 3.3 | 0.922 | 2.8 |
|
| ||||
| 8 | 0.903 | 2.7 | 0.793 | 2.4 |
| 9 | 0.720 | 2.2 | 0.685 | 2.1 |
| 10 | 0.615 | 1.9 | 0.596 | 1.8 |
| 11 | 0.552 | 1.7 | 0.558 | 1.7 |
| 12 | 0.495 | 1.5 | 0.514 | 1.6 |
| 13 | 0.479 | 1.5 | 0.472 | 1.4 |
| 14 | 0.407 | 1.2 | 0.360 | 1.1 |
| 15 | 0.403 | 1.2 | 0.348 | 1.1 |
| 16 | 0.361 | 1.1 | 0.330 | 1.0 |
| 17 | 0.323 | 1.0 | 0.246 | 0.7 |
| 18 | 0.314 | 1.0 | 0.233 | 0.7 |
| 19 | 0.267 | 0.8 | 0.203 | 0.6 |
| 20 | 0.265 | 0.8 | 0.194 | 0.6 |
| 21 | 0.223 | 0.7 | 0.183 | 0.6 |
| 22 | 0.203 | 0.6 | 0.147 | 0.4 |
| 23 | 0.164 | 0.5 | 0.138 | 0.4 |
| 24 | 0.145 | 0.4 | 0.115 | 0.3 |
| 25 | 0.141 | 0.4 | 0.099 | 0.3 |
| 26 | 0.109 | 0.3 | 0.058 | 0.2 |
| 27 | 0.091 | 0.3 | 0.027 | 0.1 |
| 28 | 0.077 | 0.2 | 0.013 | 0.0 |
| 29 | 0.055 | 0.2 | 0.004 | 0.0 |
| Part IV
| ||||
|---|---|---|---|---|
| English | Japanese | |||
|
| ||||
| Factor | Eigenvalues | Percent Variance | Eigenvalues | Percent Variance |
| 1 | 3.811 | 63.9 | 3.656 | 60.9 |
| 2 | 0.942 | 15.6 | 1.210 | 20.2 |
|
| ||||
| 3 | 0.640 | 10.7 | 0.725 | 12.1 |
| 4 | 0.241 | 4.0 | 0.168 | 2.8 |
| 5 | 0.208 | 3.5 | 0.130 | 2.2 |
| 6 | 0.159 | 2.3 | 0.111 | 1.9 |
dotted line shows the factors selected in the English cohort
The SCREE plots were used to determine the number of factors to be retained from the EFA. Comparison between the SCREE plots for the English and Japanese cohorts reveal similarities in shape of the plots (Figure 1), but differences were noted in the relationship between factors and their eigenvalues and percent of variance (Table 5) for Part I: Non-motor aspects of experiences of daily living, we extracted two factors. For Part II: Motor aspects of experiences of daily living we extracted three components. For Part III, Motor examination, we extracted seven factors. For Part IV: Motor complications, we extracted two factors.
Figure 1.
SCREE plots for the English and Japanese exploratory factor analyses.
Chi-square test (Table 3) revealed greater distribution of less severe scores on the Cognitive Impairment items (Part I - Item 1.1) in the Japanese group compared to the English group (χ2 = 23.457, df = 4, p = 0.0001), There was no significant difference of the distribution of scores on the Hallucinations and Psychosis item (Part I – Item 1.2) (χ2 = 5.962, df = 4, ns). In many other items, PD patients in the English group showed greater distribution of more severe scores including –Depressed mood, Pain and other sensations, Light headedness on standing, Fatigue, and Sleep problems in Part I; Speech, Saliva and drooling, Doing hobbies and other activities, Tremor, Getting out of bed in Part II; Speech Facial expression, Rigidity, Finger tapping, hand movements, Pronation supination, Toe tapping, Leg agility, and tremor in Part III; and, Time spent with dyskinesia, Functional impact of dyskinesias, Time spent in the OFF state, Complexity of motor fluctuations, and Painful off state dystonia in Part IV. Japanese PD patients showed greater distribution in more severe scores than English groups in items Constipation problems in Part I and Postural stability in Part III.
Table 3.
Distribution of Responses by MDS-UPDRS by English- and Japanese-Language
| Part I
| |||||||||
|---|---|---|---|---|---|---|---|---|---|
| English | Japanese | English | Japanese | ||||||
|
| |||||||||
| Cognitive impairment* | Freq. | % | Freq. | % | Daytime sleepiness | Freq. | % | Freq. | % |
| 0 | 428 | 48.86 | 227 | 62.19 | 0 | 212 | 24.2 | 104 | 28.49 |
| 1 | 256 | 29.22 | 93 | 25.48 | 1 | 216 | 24.66 | 73 | 20.00 |
| 2 | 121 | 13.81 | 25 | 6.85 | 2 | 364 | 41.55 | 147 | 40.27 |
| 3 | 53 | 6.05 | 17 | 4.66 | 3 | 59 | 6.74 | 32 | 8.77 |
| 4 | 17 | 1.94 | 3 | 0.82 | 4 | 16 | 1.83 | 8 | 2.19 |
| 999 | 1 | 0.11 | 0 | 0.00 | 999 | 9 | 1.03 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Hallucinations and psychosis | Freq. | % | Freq. | % | Pain and other sensations* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 687 | 78.42 | 280 | 76.71 | 0 | 303 | 34.59 | 148 | 40.55 |
| 1 | 89 | 10.16 | 38 | 10.41 | 1 | 289 | 32.99 | 117 | 32.05 |
| 2 | 51 | 5.82 | 26 | 7.12 | 2 | 130 | 14.84 | 60 | 16.44 |
| 3 | 35 | 4 | 14 | 3.84 | 3 | 106 | 12.1 | 31 | 8.49 |
| 4 | 13 | 1.48 | 4 | 1.10 | 4 | 39 | 4.45 | 4 | 1.10 |
| 999 | 1 | 0.11 | 3 | 0.82 | 999 | 9 | 1.03 | 5 | 1.37 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Depressed mood* | Freq. | % | Freq. | % | Urinary problems | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 471 | 53.77 | 223 | 61.10 | 0 | 325 | 37.1 | 144 | 39.45 |
| 1 | 265 | 30.25 | 84 | 23.01 | 1 | 281 | 32.08 | 118 | 32.33 |
| 2 | 81 | 9.25 | 36 | 9.86 | 2 | 137 | 15.64 | 60 | 16.44 |
| 3 | 45 | 5.14 | 21 | 5.75 | 3 | 88 | 10.05 | 32 | 8.77 |
| 4 | 12 | 1.37 | 0 | 0.00 | 4 | 38 | 4.34 | 10 | 2.74 |
| 999 | 2 | 0.23 | 1 | 0.27 | 999 | 7 | 0.8 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Anxious mood | Freq. | % | Freq. | % | Constipation problems* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 413 | 47.15 | 192 | 52.60 | 0 | 384 | 43.84 | 90 | 24.66 |
| 1 | 307 | 35.05 | 116 | 31.78 | 1 | 287 | 32.76 | 120 | 32.88 |
| 2 | 96 | 10.96 | 39 | 10.68 | 2 | 119 | 13.58 | 74 | 20.27 |
| 3 | 41 | 4.68 | 15 | 4.11 | 3 | 70 | 7.99 | 63 | 17.26 |
| 4 | 17 | 1.94 | 1 | 0.27 | 4 | 9 | 1.03 | 18 | 4.93 |
| 999 | 2 | 0.23 | 2 | 0.55 | 999 | 7 | 0.8 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Apathy | Freq. | % | Freq. | % | Light headedness on standing* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 584 | 66.67 | 249 | 68.22 | 0 | 490 | 55.94 | 238 | 65.21 |
| 1 | 141 | 16.1 | 61 | 16.71 | 1 | 216 | 24.66 | 78 | 21.37 |
| 2 | 88 | 10.05 | 27 | 7.40 | 2 | 103 | 11.76 | 37 | 10.14 |
| 3 | 52 | 5.94 | 20 | 5.48 | 3 | 51 | 5.82 | 10 | 2.74 |
| 4 | 8 | 0.91 | 7 | 1.92 | 4 | 9 | 1.03 | 1 | 0.27 |
| 999 | 3 | 0.34 | 1 | 0.27 | 999 | 7 | 0.8 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Features of DDS | Freq. | % | Freq. | % | Fatigue* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 747 | 85.27 | 315 | 86.30 | 0 | 217 | 24.77 | 141 | 38.63 |
| 1 | 57 | 6.51 | 23 | 6.30 | 1 | 335 | 38.24 | 128 | 35.07 |
| 2 | 44 | 5.02 | 20 | 5.48 | 2 | 184 | 21 | 57 | 15.62 |
| 3 | 19 | 2.17 | 4 | 1.10 | 3 | 81 | 9.25 | 33 | 9.04 |
| 4 | 6 | 0.68 | 0 | 0.00 | 4 | 50 | 5.71 | 4 | 1.10 |
| 999 | 3 | 0.34 | 3 | 0.82 | 999 | 9 | 1.03 | 2 | 0.55 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Sleep problems* | Freq. | % | Freq. | % | |||||
|
| |||||||||
| 0 | 280 | 31.96 | 138 | 37.81 | |||||
| 1 | 202 | 23.06 | 103 | 28.22 | |||||
| 2 | 207 | 23.63 | 81 | 22.19 | |||||
| 3 | 140 | 15.98 | 39 | 10.68 | |||||
| 4 | 40 | 4.57 | 3 | 0.82 | |||||
| 999 | 7 | 0.8 | 1 | 0.27 | |||||
| Total | 876 | 100 | 365 | 100.00 | |||||
| Part II
| |||||||||
|---|---|---|---|---|---|---|---|---|---|
| English | Japanese | English | Japanese | ||||||
|
| |||||||||
| Speech* | Freq. | % | Freq. | % | Doing hobbies and other activities* | Freq. | % | Freq. | % |
| 0 | 252 | 28.77 | 159 | 43.56 | 0 | 227 | 25.91 | 130 | 35.62 |
| 1 | 236 | 26.94 | 78 | 21.37 | 1 | 289 | 32.99 | 99 | 27.12 |
| 2 | 233 | 26.6 | 82 | 22.47 | 2 | 185 | 21.12 | 65 | 17.81 |
| 3 | 126 | 14.38 | 43 | 11.78 | 3 | 81 | 9.25 | 41 | 11.23 |
| 4 | 22 | 2.51 | 3 | 0.82 | 4 | 84 | 9.59 | 29 | 7.95 |
| 999 | 7 | 0.8 | 0 | 0.00 | 999 | 10 | 1.14 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Saliva and drooling* | Freq. | % | Freq. | % | Turning in bed | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 341 | 38.93 | 186 | 50.96 | 0 | 277 | 31.62 | 122 | 33.42 |
| 1 | 115 | 13.13 | 49 | 13.42 | 1 | 378 | 43.15 | 144 | 39.45 |
| 2 | 203 | 23.17 | 64 | 17.53 | 2 | 111 | 12.67 | 48 | 13.15 |
| 3 | 157 | 17.92 | 46 | 12.60 | 3 | 55 | 6.28 | 31 | 8.49 |
| 4 | 53 | 6.05 | 18 | 4.93 | 4 | 50 | 5.71 | 19 | 5.21 |
| 999 | 7 | 0.8 | 2 | 0.55 | 999 | 5 | 0.57 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Chewing and swallowing | Freq. | % | Freq. | % | Tremor* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 549 | 62.67 | 241 | 66.03 | 0 | 189 | 21.58 | 118 | 32.33 |
| 1 | 230 | 26.26 | 81 | 22.19 | 1 | 360 | 41.1 | 154 | 42.19 |
| 2 | 54 | 6.16 | 22 | 6.03 | 2 | 212 | 24.2 | 69 | 18.90 |
| 3 | 34 | 3.88 | 18 | 4.93 | 3 | 72 | 8.22 | 17 | 4.66 |
| 4 | 3 | 0.34 | 3 | 0.82 | 4 | 36 | 4.11 | 7 | 1.92 |
| 999 | 6 | 0.68 | 0 | 0.00 | 999 | 7 | 0.8 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Eating tasks | Freq. | % | Freq. | % | Getting out of bed* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 363 | 41.44 | 158 | 43.29 | 0 | 180 | 20.55 | 101 | 27.67 |
| 1 | 265 | 30.25 | 114 | 31.23 | 1 | 317 | 36.19 | 140 | 38.36 |
| 2 | 187 | 21.35 | 79 | 21.64 | 2 | 199 | 22.72 | 73 | 20.00 |
| 3 | 42 | 4.79 | 8 | 2.19 | 3 | 104 | 11.87 | 35 | 9.59 |
| 4 | 10 | 1.14 | 5 | 1.37 | 4 | 70 | 7.99 | 15 | 4.11 |
| 999 | 9 | 1.03 | 1 | 0.27 | 999 | 6 | 0.68 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Dressing | Freq. | % | Freq. | % | Walking and balance | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 220 | 25.11 | 82 | 22.47 | 0 | 184 | 21 | 74 | 20.27 |
| 1 | 322 | 36.76 | 176 | 48.22 | 1 | 336 | 38.36 | 156 | 42.74 |
| 2 | 211 | 24.09 | 67 | 18.36 | 2 | 105 | 11.99 | 38 | 10.41 |
| 3 | 76 | 8.68 | 28 | 7.67 | 3 | 172 | 19.63 | 61 | 16.71 |
| 4 | 42 | 4.79 | 12 | 3.29 | 4 | 74 | 8.45 | 33 | 9.04 |
| 999 | 5 | 0.57 | 0 | 0.00 | 999 | 5 | 0.57 | 3 | 0.82 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Hygiene | Freq. | % | Freq. | % | Freezing | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 342 | 39.04 | 126 | 34.52 | 0 | 453 | 51.71 | 176 | 48.22 |
| 1 | 367 | 41.89 | 160 | 43.84 | 1 | 182 | 20.78 | 74 | 20.27 |
| 2 | 88 | 10.05 | 47 | 12.88 | 2 | 89 | 10.16 | 40 | 10.96 |
| 3 | 33 | 3.77 | 25 | 6.85 | 3 | 90 | 10.27 | 49 | 13.42 |
| 4 | 38 | 4.34 | 7 | 1.92 | 4 | 56 | 6.39 | 25 | 6.85 |
| 999 | 8 | 0.91 | 0 | 0.00 | 999 | 6 | 0.68 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Handwriting | Freq. | % | Freq. | % | |||||
|
| |||||||||
| 0 | 161 | 18.38 | 106 | 29.04 | |||||
| 1 | 251 | 28.65 | 151 | 41.37 | |||||
| 2 | 222 | 25.34 | 75 | 20.55 | |||||
| 3 | 146 | 16.67 | 22 | 6.03 | |||||
| 4 | 87 | 9.93 | 11 | 3.01 | |||||
| 999 | 9 | 1.03 | 0 | 0.00 | |||||
| Total | 876 | 100 | 365 | 100.00 | |||||
| Part III
| |||||||||
|---|---|---|---|---|---|---|---|---|---|
| English | Japanese | English | Japanese | ||||||
|
| |||||||||
| Speech* | Freq. | % | Freq. | % | Arising from chair | Freq. | % | Freq. | % |
| 0 | 189 | 21.58 | 148 | 40.55 | 0 | 422 | 48.17 | 197 | 53.97 |
| 1 | 379 | 43.26 | 143 | 39.18 | 1 | 245 | 27.97 | 106 | 29.04 |
| 2 | 213 | 24.32 | 53 | 14.52 | 2 | 78 | 8.9 | 24 | 6.58 |
| 3 | 69 | 7.88 | 15 | 4.11 | 3 | 71 | 8.11 | 22 | 6.03 |
| 4 | 22 | 2.51 | 4 | 1.10 | 4 | 55 | 6.28 | 16 | 4.38 |
| 999 | 4 | 0.46 | 2 | 0.55 | 999 | 5 | 0.57 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Facial expression* | Freq. | % | Freq. | % | Gait | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 96 | 10.96 | 88 | 24.11 | 0 | 202 | 23.06 | 81 | 22.19 |
| 1 | 300 | 34.25 | 137 | 37.53 | 1 | 351 | 40.07 | 187 | 51.23 |
| 2 | 361 | 41.21 | 109 | 29.86 | 2 | 167 | 19.06 | 47 | 12.88 |
| 3 | 89 | 10.16 | 23 | 6.30 | 3 | 97 | 11.07 | 36 | 9.86 |
| 4 | 26 | 2.97 | 7 | 1.92 | 4 | 55 | 6.28 | 14 | 3.84 |
| 999 | 4 | 0.46 | 1 | 0.27 | 999 | 4 | 0.46 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Rigidity–Neck | Freq. | % | Freq. | % | Freezing of gait | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 260 | 29.68 | 134 | 36.71 | 0 | 655 | 74.77 | 250 | 68.49 |
| 1 | 247 | 28.2 | 97 | 26.58 | 1 | 95 | 10.84 | 50 | 13.70 |
| 2 | 274 | 31.28 | 92 | 25.21 | 2 | 60 | 6.85 | 30 | 8.22 |
| 3 | 73 | 8.33 | 36 | 9.86 | 3 | 26 | 2.97 | 13 | 3.56 |
| 4 | 16 | 1.83 | 4 | 1.10 | 4 | 38 | 4.34 | 19 | 5.21 |
| 999 | 6 | 0.68 | 2 | 0.55 | 999 | 2 | 0.23 | 3 | 0.82 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Rigidity–RUE* | Freq. | % | Freq. | % | Postural stability* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 176 | 20.09 | 93 | 25.48 | 0 | 422 | 48.17 | 150 | 41.10 |
| 1 | 282 | 32.19 | 142 | 38.90 | 1 | 157 | 17.92 | 66 | 18.08 |
| 2 | 342 | 39.04 | 111 | 30.41 | 2 | 60 | 6.85 | 44 | 12.05 |
| 3 | 69 | 7.88 | 14 | 3.84 | 3 | 149 | 17.01 | 84 | 23.01 |
| 4 | 6 | 0.68 | 2 | 0.55 | 4 | 86 | 9.82 | 20 | 5.48 |
| 999 | 1 | 0.11 | 3 | 0.82 | 999 | 2 | 0.23 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Rigidity–LUE* | Freq. | % | Freq. | % | Posture | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 205 | 23.4 | 99 | 27.12 | 0 | 173 | 19.75 | 78 | 21.37 |
| 1 | 268 | 30.59 | 135 | 36.99 | 1 | 337 | 38.47 | 129 | 35.34 |
| 2 | 317 | 36.19 | 121 | 33.15 | 2 | 206 | 23.52 | 84 | 23.01 |
| 3 | 77 | 8.79 | 9 | 2.47 | 3 | 125 | 14.27 | 52 | 14.25 |
| 4 | 7 | 0.8 | 1 | 0.27 | 4 | 33 | 3.77 | 21 | 5.75 |
| 999 | 2 | 0.23 | 0 | 0.00 | 999 | 2 | 0.23 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Rigidity–RLE | Freq. | % | Freq. | % | Global spontaneity of movement | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 272 | 31.05 | 109 | 29.86 | 0 | 108 | 12.33 | 49 | 13.42 |
| 1 | 248 | 28.31 | 125 | 34.25 | 1 | 278 | 31.74 | 155 | 42.47 |
| 2 | 275 | 31.39 | 106 | 29.04 | 2 | 279 | 31.85 | 97 | 26.58 |
| 3 | 67 | 7.65 | 23 | 6.30 | 3 | 184 | 21 | 51 | 13.97 |
| 4 | 10 | 1.14 | 1 | 0.27 | 4 | 27 | 3.08 | 12 | 3.29 |
| 999 | 4 | 0.46 | 1 | 0.27 | 999 | 0 | 0 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Rigidity–LLE | Freq. | % | Freq. | % | Postural tremor–Right hand | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 286 | 32.65 | 116 | 31.78 | 0 | 544 | 62.1 | 223 | 61.10 |
| 1 | 227 | 25.91 | 120 | 32.88 | 1 | 262 | 29.91 | 119 | 32.60 |
| 2 | 275 | 31.39 | 100 | 27.40 | 2 | 43 | 4.91 | 19 | 5.21 |
| 3 | 75 | 8.56 | 26 | 7.12 | 3 | 23 | 2.63 | 2 | 0.55 |
| 4 | 11 | 1.26 | 1 | 0.27 | 4 | 1 | 0.11 | 2 | 0.55 |
| 999 | 2 | 0.23 | 2 | 0.55 | 999 | 3 | 0.34 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Finger tapping–Right hand* | Freq. | % | Freq. | % | Postural tremor–Left hand* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 122 | 13.93 | 95 | 26.03 | 0 | 518 | 59.13 | 234 | 64.11 |
| 1 | 342 | 39.04 | 167 | 45.75 | 1 | 276 | 31.51 | 98 | 26.85 |
| 2 | 252 | 28.77 | 64 | 17.53 | 2 | 49 | 5.59 | 27 | 7.40 |
| 3 | 144 | 16.44 | 35 | 9.59 | 3 | 29 | 3.31 | 2 | 0.55 |
| 4 | 15 | 1.71 | 3 | 0.82 | 4 | 1 | 0.11 | 1 | 0.27 |
| 999 | 1 | 0.11 | 1 | 0.27 | 999 | 3 | 0.34 | 3 | 0.82 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Finger tapping–Left hand* | Freq. | % | Freq. | % | Kinetic tremor–Right hand* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 108 | 12.33 | 91 | 24.93 | 0 | 546 | 62.33 | 258 | 70.68 |
| 1 | 298 | 34.02 | 135 | 36.99 | 1 | 265 | 30.25 | 89 | 24.38 |
| 2 | 265 | 30.25 | 96 | 26.30 | 2 | 46 | 5.25 | 15 | 4.11 |
| 3 | 181 | 20.66 | 37 | 10.14 | 3 | 13 | 1.48 | 1 | 0.27 |
| 4 | 22 | 2.51 | 5 | 1.37 | 4 | 2 | 0.23 | 1 | 0.27 |
| 999 | 2 | 0.23 | 1 | 0.27 | 999 | 4 | 0.46 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Hand movements–Right hand* | Freq. | % | Freq. | % | Kinetic tremor–Left hand* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 187 | 21.35 | 129 | 35.34 | 0 | 493 | 56.28 | 236 | 64.66 |
| 1 | 346 | 39.5 | 160 | 43.84 | 1 | 293 | 33.45 | 105 | 28.77 |
| 2 | 231 | 26.37 | 57 | 15.62 | 2 | 72 | 8.22 | 22 | 6.03 |
| 3 | 98 | 11.19 | 17 | 4.66 | 3 | 14 | 1.6 | 1 | 0.27 |
| 4 | 12 | 1.37 | 2 | 0.55 | 4 | 0 | 0 | 1 | 0.27 |
| 999 | 2 | 0.23 | 0 | 0.00 | 999 | 4 | 0.46 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Hand movements–Left hand* | Freq. | % | Freq. | % | Rest tremor amplitude–RUE* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 164 | 18.72 | 118 | 32.33 | 0 | 586 | 66.89 | 281 | 76.99 |
| 1 | 311 | 35.5 | 147 | 40.27 | 1 | 112 | 12.79 | 51 | 13.97 |
| 2 | 250 | 28.54 | 78 | 21.37 | 2 | 121 | 13.81 | 26 | 7.12 |
| 3 | 125 | 14.27 | 17 | 4.66 | 3 | 53 | 6.05 | 6 | 1.64 |
| 4 | 25 | 2.85 | 4 | 1.10 | 4 | 3 | 0.34 | 1 | 0.27 |
| 999 | 1 | 0.11 | 1 | 0.27 | 999 | 1 | 0.11 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Pronation-supination movements–Right hand* | Freq. | % | Freq. | % | Rest tremor amplitude–LUE* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 199 | 22.72 | 100 | 27.40 | 0 | 603 | 68.84 | 280 | 76.71 |
| 1 | 335 | 38.24 | 159 | 43.56 | 1 | 120 | 13.7 | 56 | 15.34 |
| 2 | 216 | 24.66 | 64 | 17.53 | 2 | 99 | 11.3 | 20 | 5.48 |
| 3 | 107 | 12.21 | 35 | 9.59 | 3 | 45 | 5.14 | 9 | 2.47 |
| 4 | 17 | 1.94 | 6 | 1.64 | 4 | 5 | 0.57 | 0 | 0.00 |
| 999 | 2 | 0.23 | 1 | 0.27 | 999 | 4 | 0.46 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Pronation-supination movements–Left hand | Freq. | % | Freq. | % | Rest tremor amplitude–RLE | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 162 | 18.49 | 76 | 20.82 | 0 | 777 | 88.7 | 319 | 87.40 |
| 1 | 297 | 33.9 | 138 | 37.81 | 1 | 52 | 5.94 | 25 | 6.85 |
| 2 | 235 | 26.83 | 101 | 27.67 | 2 | 35 | 4 | 18 | 4.93 |
| 3 | 150 | 17.12 | 42 | 11.51 | 3 | 9 | 1.03 | 2 | 0.55 |
| 4 | 29 | 3.31 | 8 | 2.19 | 4 | 0 | 0 | 0 | 0.00 |
| 999 | 3 | 0.34 | 0 | 0.00 | 999 | 3 | 0.34 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Toe tapping–Right foot* | Freq. | % | Freq. | % | Rest tremor amplitude–LLE | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 168 | 19.18 | 89 | 24.38 | 0 | 795 | 90.75 | 319 | 87.40 |
| 1 | 323 | 36.87 | 149 | 40.82 | 1 | 46 | 5.25 | 24 | 6.58 |
| 2 | 228 | 26.03 | 96 | 26.30 | 2 | 20 | 2.28 | 17 | 4.66 |
| 3 | 129 | 14.73 | 24 | 6.58 | 3 | 12 | 1.37 | 2 | 0.55 |
| 4 | 27 | 3.08 | 6 | 1.64 | 4 | 0 | 0 | 0 | 0.00 |
| 999 | 1 | 0.11 | 1 | 0.27 | 999 | 3 | 0.34 | 3 | 0.82 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Toe tapping–Left foot* | Freq. | % | Freq. | % | Rest tremor amplitude–Lip/jaw* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 154 | 17.58 | 68 | 18.63 | 0 | 780 | 89.04 | 349 | 95.62 |
| 1 | 251 | 28.65 | 140 | 38.36 | 1 | 63 | 7.19 | 12 | 3.29 |
| 2 | 268 | 30.59 | 111 | 30.41 | 2 | 18 | 2.05 | 3 | 0.82 |
| 3 | 154 | 17.58 | 36 | 9.86 | 3 | 13 | 1.48 | 0 | 0.00 |
| 4 | 46 | 5.25 | 10 | 2.74 | 4 | 1 | 0.11 | 1 | 0.27 |
| 999 | 3 | 0.34 | 0 | 0.00 | 999 | 1 | 0.11 | 0 | 0.00 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Leg agility–Right leg* | Freq. | % | Freq. | % | Constancy of rest* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 250 | 28.54 | 119 | 32.60 | 0 | 409 | 46.69 | 219 | 60.00 |
| 1 | 329 | 37.56 | 163 | 44.66 | 1 | 214 | 24.43 | 79 | 21.64 |
| 2 | 190 | 21.69 | 61 | 16.71 | 2 | 91 | 10.39 | 28 | 7.67 |
| 3 | 86 | 9.82 | 18 | 4.93 | 3 | 85 | 9.7 | 21 | 5.75 |
| 4 | 18 | 2.05 | 4 | 1.10 | 4 | 67 | 7.65 | 17 | 4.66 |
| 999 | 3 | 0.34 | 0 | 0.00 | 999 | 10 | 1.14 | 1 | 0.27 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Leg agility–Left leg* | Freq. | % | Freq. | % | |||||
|
| |||||||||
| 0 | 216 | 24.66 | 99 | 27.12 | |||||
| 1 | 298 | 34.02 | 142 | 38.90 | |||||
| 2 | 213 | 24.32 | 90 | 24.66 | |||||
| 3 | 106 | 12.1 | 30 | 8.22 | |||||
| 4 | 38 | 4.34 | 3 | 0.82 | |||||
| 999 | 5 | 0.57 | 1 | 0.27 | |||||
| Total | 876 | 100 | 365 | 100.00 | |||||
| Part IV
| |||||||||
|---|---|---|---|---|---|---|---|---|---|
| English | Japanese | English | Japanese | ||||||
|
| |||||||||
| Time spent with dyskinesias* | Freq. | % | Freq. | % | Functional impact of fluctuations | Freq. | % | Freq. | % |
| 0 | 563 | 64.27 | 273 | 74.79 | 0 | 433 | 49.43 | 194 | 53.15 |
| 1 | 173 | 19.75 | 41 | 11.23 | 1 | 165 | 18.84 | 56 | 15.34 |
| 2 | 87 | 9.93 | 30 | 8.22 | 2 | 81 | 9.25 | 32 | 8.77 |
| 3 | 27 | 3.08 | 12 | 3.29 | 3 | 119 | 13.58 | 60 | 16.44 |
| 4 | 17 | 1.94 | 6 | 1.64 | 4 | 63 | 7.19 | 19 | 5.21 |
| 999 | 9 | 1.03 | 3 | 0.82 | 999 | 15 | 1.71 | 4 | 1.10 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Functional impact of dyskinesias* | Freq. | % | Freq. | % | Complexity of motor fluctuations* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 695 | 79.34 | 308 | 84.38 | 0 | 404 | 46.12 | 192 | 52.60 |
| 1 | 90 | 10.27 | 27 | 7.40 | 1 | 291 | 33.22 | 125 | 34.25 |
| 2 | 29 | 3.31 | 19 | 5.21 | 2 | 69 | 7.88 | 21 | 5.75 |
| 3 | 46 | 5.25 | 7 | 1.92 | 3 | 50 | 5.71 | 17 | 4.66 |
| 4 | 5 | 0.57 | 2 | 0.55 | 4 | 46 | 5.25 | 3 | 0.82 |
| 999 | 11 | 1.26 | 2 | 0.55 | 999 | 16 | 1.83 | 7 | 1.92 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
|
| |||||||||
| Time spent in the OFF state* | Freq. | % | Freq. | % | Painful OFF-state dystonia* | Freq. | % | Freq. | % |
|
| |||||||||
| 0 | 383 | 43.72 | 183 | 50.14 | 0 | 680 | 77.63 | 319 | 87.40 |
| 1 | 341 | 38.93 | 113 | 30.96 | 1 | 114 | 13.01 | 28 | 7.67 |
| 2 | 106 | 12.1 | 50 | 13.70 | 2 | 45 | 5.14 | 4 | 1.10 |
| 3 | 22 | 2.51 | 14 | 3.84 | 3 | 13 | 1.48 | 6 | 1.64 |
| 4 | 14 | 1.6 | 2 | 0.55 | 4 | 15 | 1.71 | 5 | 1.37 |
| 999 | 10 | 1.14 | 3 | 0.82 | 999 | 9 | 1.03 | 3 | 0.82 |
| Total | 876 | 100 | 365 | 100.00 | Total | 876 | 100 | 365 | 100.00 |
999 = missing
; p < 0.05 by chi-square test (df = 4)
Discussion
The overall factor structure of the Japanese version was consistent with the English version based on the CFIs for all four parts of the MDS-UPDRS in the confirmatory factor analysis (all CFI ≥ 0.93). The Japanese scale was confirmed to share a common factor structure with the English scale. Therefore, this version can be designated as the OFFICIAL JAPANESE VERSION OF THE MDS-UPDRS.
Exploratory factor analysis, in which variability from sample to sample is expected, identified isolated item differences of factor structure between the Japanese and English versions of the MDS-UPDRS. However, the distribution of factors with their associated eigenvalues and percent variances were similar across the two languages.
In our study, female preponderance was noted as the previous study reported from Japan. 4 This may in part be due to the longer life expectancy (by approximately 6.5 years) in Japanese women in comparison to men.
Another interesting difference between the Japanese and English language versions data sets for the MDS-UPDRS concerned the pattern of responses to Item 1.1-Cognitive Impairment and Item 1.2 - Hallucinations and Psychosis. For the Hallucination item, the Japanese and English frequencies for each rating option were very similar (77% and 78% respectively), but Cognitive Impairment ratings were different in the two cultures. A much greater percentage (62.2%) of Japanese had 0 scores in comparison to the English-speaking sample (48.9%). In general, among reports in Western cultures, cognitive impairment and hallucinations are shared or overlapping behaviors and such data have been used to argue shared common pathogeneses.15,16 Results of chi-square test indicate that severity of motor and non-motor symptoms are generally more severe in patients of English groups than those of Japanese groups. Even after taking these differences into consideration, the present results from the Japanese sample may indicate that cognitive impairment is less frequent or viewed differently and thereby may be underreported for cultural reasons in Japan in comparison to the Western culture.
Contrary to majority of items, Constipation problems and Postural stability were rated more severe in Japanese patients than English patients. Differences in genetic factor, eating habits, and amount of daily exercise between two populations are possible factors to produce different response to the former item. The reason why Postural stability was rated more severely in Japanese groups remains unknown. Factors including examiner’s manner to pull patients may be clarified in future.
In conclusion, the CFI for the Japanese version of the MDS-UPDRS was 0.93 or greater. Therefore, the Japanese version meets the criterion for designation as an official translation of the MDS-UPDRS. This is the first Asian or non-Indo-European language translation of the MDS-UPDRS. The Japanese version of the MDS-UPDRS is available from the MDS website (http://www.movementdisorders.org/publications/rating_scales/). The establishment of additional non-English translations will further facilitate the understanding of PD symptoms and help accelerate qualified clinical trials and discussions worldwide.
Footnotes
Author roles
Kenichi Kashihara:
Research project - conception, organization, execution
Statistical analysis - review and critique
Manuscript preparation - writing of the first draft, critique and review
Tomoyoshi Kondo:
Research project - conception, organization, execution
Manuscript preparation - writing of the first draft, critique and review
Yoshikuni Mizuno:
Research project - conception, organization, execution
Manuscript preparation - writing of the first draft, critique and review
Seiji Kikuchi:
Research project - organization, execution
Manuscript preparation - critique and review
Sadako Kuno:
Research project - organization, execution
Manuscript preparation - critique and review
Kazuko Hasegawa:
Research project - organization, execution
Manuscript preparation - writing of the first draft, critique and review
Nobutaka Hattori:
Research project - organization, execution
Manuscript preparation - critique and review
Hideki Mochizuki:
Research project - organization, execution
Manuscript preparation - critique and review
Hideo Mori:
Research project - organization, execution
Manuscript preparation - critique and review
Miho Murata:
Research project - organization, execution
Manuscript preparation - critique and review
Masahiro Nomoto:
Research project - organization, execution
Manuscript preparation - critique and review
Ryosuke Takahashi:
Research project - organization, execution
Manuscript preparation - critique and review
Atsushi Takeda:
Research project - organization, execution
Manuscript preparation - critique and review
Yoshio Tsuboi:
Research project - organization, execution
Manuscript preparation - critique and review
Yoshikazu Ugawa:
Research project - organization, execution
Manuscript preparation - critique and review
Mitsutoshi Yamamoto:
Research project - organization, execution
Manuscript preparation - critique and review
Fusako Yokochi:
Research project - organization, execution
Manuscript preparation - critique and review
Fumihito Yoshii:
Research project - conception, organization, execution
Manuscript preparation - writing of the first draft, critique and review
Glenn T. Stebbins:
Research project - conception, organization, execution
Statistical analysis - design, review and critique
Manuscript preparation - review and critique
BC Tilley:
Statistical analysis - review and critique
Manuscript preparation - review and critique
L Wang:
Statistical analysis - conducts and review
Manuscript preparation - methods section and review
S Luo:
Statistical analysis - review and critique
Manuscript preparation - review and critique
Nancy R. LaPelle:
Cognitive pre-testing - design and data analysis
Manuscript prep - review and critique
Christopher G. Goetz:
Research project - conception, organization, execution
Statistical analysis - design, review and critique
Manuscript preparation - writing of the first draft, critique and review
Financial disclosure
Funding Sources and Conflict of Interest:
This work was supported by Boehringer-Ingelheim Japan. The Administrative Core members (GTS, BCT, SL, LW, NRL and CGG) were supported by funds from the Movement Disorder Society.
Financial disclosures for the previous 12 months:
Kenichi Kashihara reports the following:
Advisory Boards: Kyowa Hakko Kirin Co.
Grants: Health and Labour Sciences Research Grants
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co.
Royalties: Nankodo.
Tomoyoshi Kondo reports the following:
Consultant: Kyowa Hakko Kirin Co., NOVARTIS.
Honoraria: Boeringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co.
Yoshikuni Mizuno reports the following:
Advisory Board Membership: FP Pharmaceutical Co., Otsuka Pharmaceutical Co., AbbVie Japan, Kyowa Hakko Kirin Co., and he received personal compensation when he attended advisory board meetings.
Grants: Boehringer Ingelheim.
Seiji Kikuchi reports the following:
Grants: the Ministry of Health, Labour and Welfare of Japan.
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Daiichi-Sankyo, Takeda Pharmaceutical Co., Biogen Idec Japan, Bayer Yakuhin, Genzyme Japan, Nihon Pharmaceutical Co., Mitsubishi Tanabe Pharma.
Sadako Kuno reports the following:
Advisory Boards: AbbVie Japan.
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Ono Pharmaceutical Co., AbbVie Japan, Alfresa Pharma.
Kazuko Hasegawa reports the following:
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co.
Nobutaka Hattori reports the following:
Consultant: Hisamitsu Pharmaceutical.
Grants: Otsuka Pharmaceutical, Boehringer Ingelheim, Kyowa Hakko-Kirin Pharmaceutical Company.
Honoraria: GlaxoSmithKleine K.K, Nippon Boehringer Ingelheim, Co.,Ltd, FP Pharmaceutical Corporation, Otsuka Pharmaceutical, Co.,Ltd., Dai-Nippon Sumitomo Pharma Co.,Ltd., Novartis Pharma K.K, Eisai Co.,Ltd., Medtronic, Inc., Kissei Pharmaceutical Company, Janssen Pharmaceutical K.K, Nihon Medi-physics Co.,Ltd., Astellas Pharma Inc., and Kyowa Hakko-Kirin Co.,Ltd.
Hideki Mochizuki reports the following:
Grants: Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science & Technology in Japan, Grant-in-Aid for JST-CREST Basic Research Program from the Ministry of Education, Culture, Sports, Science & Technology in Japan, Grant-in-Aid for Scientific Research on Innovative Areas (Brain Environment) from the Ministry of Education, Science, Sports and Culture of Japan, Grant-in-Aid for Research on Applying Health Technology from the Ministry of Health, Labour and Welfare of Japan.
Honoraria: Biogen Idec Japan, Eisai Co., Ltd., FP Pharmaceutical Co., Elsevier Japan, Hisamitsu Pharma, Kyowa Hakko Kirin Co., Glaxo Smith Kline, Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co. Takeda Pharmaceutical Co., Mitsubishi Tanabe Pharma, Nippon Chemiphar Co., Nihon Medi-Physics Co., Boehringer Ingelheim, NOVARTIS, UCB Japan.
Royalties: Nature Japan, Igaku-Shoin, Iyaku Journal, Nanzando Co., Kinpodo.
Hideo Mori reports the following:
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co.
Miho Murata reports the following:
Grants: the Ministry of Health, Labour and Welfare of Japan.
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Kyowa Hakko Kirin Co., NOVARTIS, Otsuka Pharmaceutical Co., Dainippon Sumitomo Pharm Co., Nihon Medi-Physics Co.
Masahiro Nomoto reports the following:
Grants/Research Support: the Ministry of Health, Labour and Welfare of Japan. Dainippon Sumitomo Pharm Co., Boehringer Ingelheim, NOVARTIS, Glaxo Simith Kline, FP Pharmaceutical Co., Genzyme, Tsumura & Co.
Consulting and Advisory Board Membership with honoraria: the Japanese Society of Internal Medicine, Takeda Pharm Co., FP Pharm Co., Kyowa Hakko Kirin Co., Otsuka Pharm Co., Hisamitsu, Ono Pharm Co., Meiji Seika,
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Dainippon Sumitomo Pharm Co., FP Pharm Co., NOVARTIS, Kyowa Hakko Kirin Co., Otsuka Pharm Co., Genzyme, Panasonic Healthcare Co., UCB INC.
Royalties: Maruzen, Igaku-Shoin, Nishimura.
Ryosuke Takahashi reports the following:
Consultant: KAN Research Institute, Inc., Daiichi-Sankyo.
Grants/Research Support: Dainippon Sumitomo Pharm Co., Boehringer Ingelheim, NOVARTIS, Pfizer Co., Ltd., Glaxo Simith Kline, Takeda Pharmaceutical Co., Mitsubishi Tanabe Pharma, Kyowa Hakko Kirin Co.
Honoraria: Boehringer Ingelheim, Glaxo Smith Kline, Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Medical Review, NOVARTIS, Daiichi-Sankyo, Kyowa Hakko Kirin Co., Mitsubishi Tanabe Pharma, Eisai Co., Ltd., Nihon Pharmaceutical Co., Otsuka Pharmaceutical Co., Janssen Pharmaceutical Company, SANOFI, Alfresa Pharma Co., Japan Blood Products Organization, ASBIO Pharma Co., MSD.
Atsushi Takeda reports the following:
Grants: the Ministry of Education, Culture, Sports, Science and Technology of Japan, the Ministry of Health, Labour and Welfare of Japan.
Honoraria: Otsuka Pharmaceutical Co., Kyowa Hakko Kirin Co., Ltd., Glaxo Smith Kline, Daiichi-Sankyo, Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Takeda Pharmaceutical Co., Boehringer Ingelheim, NOVARIS, Ono Pharmaceutical,
Royalties: Iyaku Journal, Chugai-Igakusha, Igaku-Shoin, Medical View, Elsevier Japan, Aruta Shuppan.
Yoshio Tsuboi reports the following:
Grants: the Ministry of Health, Labour and Welfare of Japan.
Honoraria: Eisai Co., Ltd., Otsuka Pharmaceutical Co., Kyowa Hakko Kirin Co., Glaxo Smith Kline, Daiichi-Sankyo, Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Mitsubishi Tanabe Pharma, Teijin Pharma, Boehringer Ingelheim, NOVARTIS.
Yoshikazu Ugawa reports the following: Grants: the Ministry of Education, Culture, Sports, Science and Technology of Japan, the Ministry of Health, Labour and Welfare of Japan, the Support Center for Advanced Telecommunications Technology Research, the Association of Radio Industries Businesses, the Uehara Memorial Foundation, NOVARTIS Foundation (Japan) for the Promotion of Science, JST, Nihon Kohden.
Honoraria: Taiwan Society of Clinical Neurophysiology, Indonesia Society of Clinical Neurophysiology, Taiwan Movement Disoders Society, Astellas Pharma, Eisai Co. Ltd., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co., Otsuka Pharmaceutical Co., Elsevier Japan, Kissei Pharmaceutical Co., Kyorin Pharma, Kyowa Hakko Kirin Co., Glaxo Smith Kline, SANOFI, Daiichi-Sankyo, Takeda Pharmaceutical Co., Mitsubishi Tanebe Pharma, Teijin Pharma, Nippon Chemiphar Co., Nihon Pharmaceutical Co., Boehringer Ingelheim, NOVARTIS, Bayer Yakuhin, Mochida Pharma.
Royalties: Chugai-Igakusha, Igaku-Shoin Ltd, Medical View, Blackwell Publishing.
Mitsutoshi Yamamoto reports the following:
Honoraria: Dainippon Sumitomo Pharm Co., Boehringer Ingelheim, NOVARTIS, Glaxo Simith Kline, FP Pharmaceutical Co., Kyowa Hakko Kirin Co., Otsuka Pharm Co.
Fusako Yokochi reports the following:
Honoraria: Glaxo Smith Kline, Otsuka Pharmaceutical Co., Medtronic, AbbVie Japan
Fumihito Yoshii reports the following:
Grants: Eisai Co., Ltd., Dainippon Sumitomo Pharm Co., FP Pharmaceutical Co.
Takeda Pharmaceutical Co., Mitsubishi Tanabe Pharma, Glaxo Smith Kline, Boehringer Ingelheim, Daiichi-Sankyo, Mitsubishi Tanabe Pharma, Pfizer
Honoraria: Glaxo Smith Kline, Dainippon Sumitomo Pharm Co., Boehringer Ingelheim, NOVARTIS, AbbVie Japan, Ono Parmaceutical Co., Otsuka Pharmaceutical Co., Janssen Pharmaceutical Co.
Glenn T. Stebbins reports the following:
Consulting and Advisory Board Membership with honoraria: Adamas Pharmaceuticals, Inc., Ceregene, Inc., CHDI Management, Inc., Ingenix Pharmaceutical Services (i3 Research), Neurocrine Biosciences, Inc.
Grants and Research: National Institutes of Health, Michael J. Fox Foundation for Parkinson’s Research, Dystonia Coallition.
Honoraria: Movement Disorder Society, American Academy of Neurology, Michael J. Fox Foundation for Parkinson’s Research.
Salary: Rush University Medical Center
Barbara C Tilley reports the following:
Grants: NIH grants (NINDS, NHLBI, NIMHD, NIGMS), Pfizer Data and Safety.
Monitoring Committee, NIH Data and Safety Monitoring Committees.
Salary: University of Texas Health Science Center School of Public Health at Houston, Division of Biostatistics.
Sheng Luo has nothing to declare.
Lu Wang has nothing to declare.
Nancy R Lapelle reports the following:
Cognitive Testing, Qualitative Research, and Program/Process Evaluation Consulting:
UMass Medical School (UMMS) Lamar Soutter Library, UMass Medical School Inter-Professional Development, The Association of Academic Health Sciences Libraries, Medical University of South Carolina (MUSC) College of Nursing and Hollings Cancer Center, Movement Disorder Society
Grants/Research: Dr. Lapelle is a subcontractor on a variety of research and evaluation grants with principal investigators at UMMS and MUSC.
Christopher G. Goetz reports the following:
Consulting and Advisory Board Membership with honoraria: AOP Orphan, Addex Pharma, Advanced Studies of Medicine, Boston Scientific, CHDI, Health Advances, ICON Clinical Research, Ingenix (i3 Research), National Institutes of Health, Neurocrine, Oxford Biomedica, Synthonics.
Grants/Research: Funding from NIH, Michael J. Fox Foundation, NIH. Dr. Goetz directs the Rush Parkinson’s Disease Research Center that receives support from the Parkinson’s Disease Foundation. He directs the translation program for the MDS-UPDRS and UDysRS and receives funds from the MDS for this effort.
Honoraria: Movement Disorder Society, American Academy of Neurology, Movement Disorder Society, University of Pennsylvania, University of Chicago, University of Luxembourg.
Royalties: Oxford University Press, Elsevier Publishers, Wolters Kluwer Health-Lippincott, Wilkins and Williams.
Salary: Rush University Medical Center.
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