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When you return your corrections, please inform us if you would like to have these documents returned. Metadata of the article that will be visualized in OnlineFirst ArticleTitle Validation of the Italian version of the Movement Disorder Society—Unified Parkinson’s Disease Rating Scale Article Sub-Title Article CopyRight Springer-Verlag (This will be the copyright line in the final PDF) Journal Name Neurological Sciences Corresponding Author Family Name Antonini Particle Given Name Angelo Suffix Division Author Organization Department for Parkinson’s disease, IRCCS San Camillo Address Via Alberoni 70, Venice, Italy Email [email protected] Family Name Abbruzzese Particle Given Name Giovanni Suffix Division Department of Neurosciences, Ophthalmology and Genetics Organization Centre for Movement Disorders, University of Genoa Address Genoa, Italy Email Author Family Name Ferini-Strambi Particle Given Name Luigi Suffix Division Organization Università Vita-Salute San Raffaele Address Milan, Italy Email Author Family Name Tilley Particle Given Name Barbara Suffix Division Organization University of Texas Health Science Center School of Public Health at Houston Address Houston, USA Email Author Family Name Huang Particle Given Name Suffix Jing Division Organization University of Texas Health Science Center School of Public Health at Houston Address Houston, USA Email Author Family Name Stebbins Particle Given Name Glenn T. Suffix Division Department of Neurological Services Organization Rush University Medical Center Address Chicago, IL, USA Email Author Family Name Goetz Particle Given Name Christopher G. Suffix Division Department of Neurological Services Organization Rush University Medical Center Address Chicago, IL, USA Email Author Family Name Barone Particle Given Name Paolo Suffix Division Neurodegenerative Diseases Center Organization University of Salerno, Salerno, and IDC-Hermitage-Capodimonte Address Naples, Italy Email Received Schedule 11 February 2012 Revised Accepted 2 May 2012 Abstract The Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDSUPDRS) 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. Keywords (separated by '-') Parkinson’s disease - MDS-UPDRS - Unified Parkinson’s Disease Rating Scale - Rating scales Footnote Information The members of the MDS-UPDRS Italian Validation Study Group are given in the Appendix. Electronic supplementary material The online version of this article (doi:10.1007/s10072-012-1112-z) contains supplementary material, which is available to authorized users. Metadata of the article that will be visualized in OnlineAlone Electronic supplementary material Below is the link to the electronic supplementary material. MOESM1: Supplementary Material (PDF 434 kb). Journal: 10072 Article: 1112 Author Query Form Please ensure you fill out your response to the queries raised below and return this form along with your corrections Dear Author During the process of typesetting your article, the following queries have arisen. Please check your typeset proof carefully against the queries listed below and mark the necessary changes either directly on the proof/online grid or in the ‘Author’s response’ area provided below Query 1. Details required Kindly check the edit made in the reference [4] and correct if necessary. Author’s response Neurol Sci DOI 10.1007/s10072-012-1112-z 1 4 5 6 Angelo Antonini • Giovanni Abbruzzese • Luigi Ferini-Strambi • Barbara Tilley • Jing Huang • Glenn T. Stebbins • Christopher G. Goetz Paolo Barone • MDS-UPDRS Italian Validation Study Group 7 8 Received: 11 February 2012 / Accepted: 2 May 2012 Ó Springer-Verlag 2012 Abstract 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 nonEnglish translations. We present here the formal process for completing officially approved non-English versions of A1 A2 The members of the MDS-UPDRS Italian Validation Study Group are given in the Appendix. A3 A4 A5 Electronic supplementary material The online version of this article (doi:10.1007/s10072-012-1112-z) contains supplementary material, which is available to authorized users. A6 A7 A8 A9 A. Antonini (&) Department for Parkinson’s disease, IRCCS San Camillo, Via Alberoni 70, Venice, Italy e-mail: [email protected] • PR OO 9 10 11 12 13 14 15 F 3 Validation of the Italian version of the Movement Disorder Society—Unified Parkinson’s Disease Rating Scale 2 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 Englishlanguage 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 C0.90 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 C0.94. 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. G. Abbruzzese Department of Neurosciences, Ophthalmology and Genetics, Centre for Movement Disorders, University of Genoa, Genoa, Italy Keywords Parkinson’s disease
MDS-UPDRS
Unified Parkinson’s Disease Rating Scale
Rating scales A14 A15 L. Ferini-Strambi Università Vita-Salute San Raffaele, Milan, Italy Introduction 37 A16 A17 A18 B. Tilley
J. Huang University of Texas Health Science Center School of Public Health at Houston, Houston, USA A19 A20 A21 A22 G. T. Stebbins
C. G. Goetz Department of Neurological Services, Rush University Medical Center, Chicago, IL, USA A23 A24 A25 P. Barone Neurodegenerative Diseases Center, University of Salerno, Salerno, and IDC-Hermitage-Capodimonte, Naples, Italy After its introduction in the 1980s, the Unified Parkinson’s Disease Rating Scale (UPDRS) has become the gold standard clinical rating scale for Parkinson’s disease (PD) [1, 2]. In 2008, a new Movement Disorder Society (MDS)sponsored revision of the UPDRS, known as the MDS UPDRS, successfully passed clinimetric testing with high internal consistency and reliable factor structures for each part of the scale [3]. The new MDS-UPDRS comprises four parts: Part I evaluates non-motor experiences of daily living 38 39 40 41 42 43 44 45 46 47 CO RR E CT ED A10 A11 A12 A13 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 UN Author Proof ORIGINAL ARTICLE 123 Journal : Large 10072 Dispatch : 12-5-2012 Pages : 5 Article No. : 1112 h LE 4 CP h h TYPESET 4 DISK h MS Code : NEUS2171 Methods 69 Translation of the MDS-UPDRS 70 71 72 73 74 75 76 77 The MDS-UPDRS was translated into Italian by a team of PD expert investigators in Italy and was then back-translated by colleagues fluent in English and Italian and not involved in the original translation. This back-translation was then reviewed by a team of US experts (Glenn Stebbins, Christopher Goetz, Nancy LaPelle, and Barbara Tilley) who had been involved in the development of the original American version. 78 Cognitive pretesting 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 Cognitive pretesting using a structured interview format was performed to evaluate specific items of the MDSUPDRS in terms of task difficulty for examiner and respondent, and respondent interest, attention span, discomfort, and comprehension. Items were selected for cognitive pretesting when the observed differences were between the back-translated Italian version and the English version. In addition, questions that were identified in cognitive testing of the American version were also tested [4]. Questions included in cognitive pretesting were MDSUPDRS Parts 1.2 Hallucinations and Psychosis; 1.6 Features Of Dopamine Dysregulation Syndrome; 1.10 Urinary Problems; 2.13 Freezing; 3.12 Postural Stability; 3.17 Rest Tremor Amplitude; 4.1 Time Spent With Dyskinesias; and 4.2 Functional Impact Of Dyskinesias. Based on the results of the initial cognitive pretesting, other round(s) of 95 96 97 98 Testing of the Italian version 99 A total of 17-experienced Italian movement disorder specialists were recruited to examine native-Italian speaking PD patients who had provided informed consent. Data without patient names or medical record numbers were transferred to the analytic team via a secure website. The patient sample size for the translation study was based on the statistical need for a minimum of five subjects per item of the questionnaire [5]. Thus, as there are 65 items on the MDS-UPDRS, a sample of at least 325 patients was required. Any participants with missing values within a part were deleted from analysis of that part only. 100 101 102 103 104 105 106 107 108 109 110 Factor analysis 111 Confirmatory and exploratory factor analyses were performed using M-plus, Version 6.1 (for categorical analyses). An unweighted least squares (ULS) approach to factor estimation that minimizes the sum of squared differences between observed and estimated correlation matrices not counting diagonal elements was used. In addition, an orthogonal VARIMAX rotation that constrains the factors to be uncorrelated was used to assist in interpretation of factors. For Part III, Factor 6, all factor loadings for the Italian data were negative (in the American data, Factor 2 had negative signs for all factor loadings). This is an artifact of the quadrant of the rotation. A factor analysis using a standardized CF-VARIMAX rotation, equivalent to the VARIMAX rotation, gave similar results but without the minus signs. Since the VARIMAX rotation is more widely used, we report the VARIMAX rotation without the (-) signs. A confirmatory factor analysis (CFA) was used to determine if the factor structure for the English language MDS-UPDRS [3] could be confirmed in data collected using the Italian translation. The CFA was conducted separately for MDS-UPDRS Parts I–IV with the Italian data constrained to fall into the factors defined in the English language data and the CFA results were evaluated based on the Comparative Fit Index (CFI). To establish a successful translation and to designate that translation as an ‘Official MDS translation’ of the MDS-UPDRS, the CFI for each Part (I–IV) of the translated MDS-UPDRS had to be 0.90 or greater relative to the English language version. In the original factor structure report, three dopamine dysregulation syndromes (DDSs) had an item loading of 0.49 on Factor 1 of Part I. However, in the re-running of 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 CO RR E CT ED 68 translation and back translation and cognitive pretesting could be required. Once any issues identified during cognitive pretesting were addressed, the final translation was obtained. F (nM-EDL), Part II evaluates motor experiences of daily living (motor-EDL), Part III evaluates motor function, and Part IV evaluates motor fluctuations and dyskinesia. As with the previous version, scores are rated by a mix of both the physician and patient. Six of the 13 items in Part I (those dealing with complex behaviors) and all items in Part IV covering fluctuations and dyskinesia involve raterled interviews of the patient or caregiver. The remaining questions in Part I and all items in Part II are answered with a patient/caregiver questionnaire without direct input from the rater, and Part III involves objective examination by the rater for all items [3]. The MDS-UPDRS was specifically designed to be less ambiguous than its predecessor and the significant patient/caregiver involvement means that it is vital that they understand the questions asked of them, preferably in their mother tongue. In order to establish a successful translation and designate non-English language versions as an ‘Official MDS translation,’ the MDS has set a strict protocol and criteria for testing. We present here the Italian version of the MDS-UPDRS. PR OO 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 UN Author Proof Neurol Sci 123 Journal : Large 10072 Dispatch : 12-5-2012 Pages : 5 Article No. : 1112 h LE 4 CP h h TYPESET 4 DISK h MS Code : NEUS2171 Results 166 Cognitive pretesting 167 168 169 170 171 172 173 174 175 176 177 178 179 A total of 10 PD patients were interviewed as part of the cognitive pretesting step. One of the 10 patients interviewed had difficulty comprehending one item on Part 1 of the Italian MDS-UPDRS (question 1.2 ‘‘Hallucinations and psychosis’’). Neither patients nor their examiners identified other difficulties. A second round of cognitive pre-testing was completed by three PD patients after a modification of the Italian version of the latter question. No difficulties were identified with question 1.2 (Hallucinations and psychosis) or any other item on this second round of testing. The modified version of the scale was approved as the Official Working Draft of the Italian MDS-UPDRS for testing in a larger group of patients with PD. 180 Testing of the Italian version of the MDS-UPDRS 181 182 183 184 185 186 187 188 189 190 In total, 377 native Italian-speaking PD patients were examined by 16-experienced movement disorder specialists using the Italian translation of the MDS-UPDRS. All patients fulfilled Brain Bank diagnostic criteria for probable PD. Patient demographic characteristics are given in Table 1. For all four parts of the Italian MDS-UPDRS, the CFI, in comparison with the English-language version, was 0.94 or greater and thus the pre-specified factor structure was confirmed in the Italian data set (Table 2). Moreover, the Patients (n = 378) Ethnicity (%) Non-hispanic white 100 Other – Gender (%) Male 59.8 Female 40.2 Age (years, mean ± SD) H&Y stage F 165 Table 1 Baseline characteristics 64.5 ± 10.3 2.1 ± 0.7 PR OO the analysis for the current program, the same item had an item factor loading of only 0.19, falling outside the acceptable range to be identified with any factor in the scale. Therefore, the CFIs for the Italian translation versus the English language version were calculated both with and without the DDS item. An exploratory factor analysis (EFA) for the Italian version of MDS-UPDRS Parts I–IV using the same factor analytic approach as for the confirmatory factor analysis but without constraining the factors to follow a pre-specified factor structure was also performed. Separate SCREE plots were used in addition to the assessment of clinical interpretability of remaining factors to choose the cut-off for the number of factors to retain for each MDS-UPDRS part. The screen plot is a scatter plot of eigenvalues ranked against the amount of scale variance accounted for by each eigenvector. The number of factors can be defined by the number of eigenvectors that independently account of a significant amount of variance [6]. Once the factors were chosen, an item was retained in a factor if the factor loading for the item was C0.40. Years since PD diagnosis (mean ± SD) 7.1 ± 5.6 Years of education (mean ± SD) 9.6 ± 4.4 overall CFIs for the English language version and the Italian version with or without the DDS item reached the criterion of CFI C0.90, showing that the Italian version of the MDS-UPDRS meets the requirements for designation as an Official Translation. Exploratory factor analyses revealed some differences between the Italian and English language datasets. For Part I, in contrast to the English language version of the MDSUPDRS, Cognitive impairment loaded on Factor 2 instead of Factor 1. In Part II, 3 of 13 items loaded differently in the Italian version in comparison to the English version. In Part III, 3 of 33 items loaded differently between the two versions. Given the variability of factor estimates and the smaller sample size used in the Italian version, the analytic team considered these differences within an acceptable range. 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 Discussion 207 In order for the MDS-UPDRS to fully replace its predecessor, the UPDRS version 3, [2] as the international gold standard tool for the assessment of PD patients, it is vital that properly tested translations are made available for use in non-English speaking countries. The Italian version of the MDS-UPDRS presented here reaches the criterion to be designated as an Official translation of the MDS-UPDRS and as such is now available for use in clinical studies. The Italian dataset shared a common factor structure with the English language dataset based on the high CFIs for all Parts of the MDS-UPDRS. Isolated item differences in factor loadings were identified, but the overall factor structure of the Italian version was consistent with that of the English language version confirming its suitability for use. Since this study was conducted, a DVD-based teaching program that covers the four parts of the scale has become available with visual and verbal (English language) instructions for the uniform application [7]. It is planned 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 CO RR E CT ED 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 UN Author Proof Neurol Sci 123 Journal : Large 10072 Dispatch : 12-5-2012 Pages : 5 Article No. : 1112 h LE 4 CP h h TYPESET 4 DISK h MS Code : NEUS2171 Neurol Sci Table 2 Confirmatory factor analysis model fit Part I: Non-motor aspects of experiences of daily living (a 2-factor model) Italian CFI = 0.94, RMSEA = 0.07 (374 patients) English language CFI = 0.96, RMSEA = 0.06 (849 patients) Part II: Motor aspects of experience of daily living (a 3-factor model) Italian CFI = 0.98, RMSEA = 0.09 (369 patients) English language CFI = 0.97, RMSEA = 0.09 (851 patients) Part III: Motor examination (a 7-factor model) CFI = 0.94, RMSEA = 0.08 (363 patients) CFI = 0.95, RMSEA = 0.07 (801 patients) Part IV: Motor complications (a 2-factor model) CFI = 1.00, RMSEA = 0.06 (374 patients) English language CFI = 1.00, RMSEA = 0.04 (848 patients) CFI comparative fit index, RMSEA root mean square error of approximation necessarily recruit centers in countries where official translations are available, so this effort has very practical implications for future patient and research programs. 239 240 241 Acknowledgments The authors wish to acknowledge all the investigators and patients who took part in this translation. Editorial assistance (editing and referencing) was provided by Anita ChadhaPatel PhD, who was supported by an unrestricted grant from the Neureca Foundation for movement disorders, Milan, Italy. 242 243 244 245 246 Appendix 247 CT ED that this teaching program will also be translated into different languages and that this will further encourage international consistency of rating with this important new tool. The Italian version of the MDS-UPDRS is the first officially approved non-English translation. The global program now includes two other completed translations (Spanish and Estonian) in statistical review and other language teams are organized for Chinese, Dutch, French, German, Hebrew, Japanese, Korean, Russian, Slovakian and Thai versions. Other language teams are encouraged to organize and participate (email contact: CG Goetz, [email protected]). Large-scale clinical trials using the MDS-UPDRS will See Table 3 248 Table 3 MDS-UPDRS Italian Validation Study Group Investigators Affiliation CO RR E 226 227 228 229 230 231 232 233 234 235 236 237 238 Monica Bandettini di Poggio Department of Neurosciences, Ophthalmology and Genetics, Centre for Movement Disorders, University of Genoa, Genoa, Italy Giovanni Fabbrini Department of Neurology and Psychiatry, Sapienza University of Rome Flavio Di Stasio Michele Tinazzi Tommaso Bovi Silvia Ramat Sara Meoni Gianni Pezzoli Margherita Canesi Paolo Martinelli Department of Neurology and Psychiatry, Sapienza University of Rome Dipartimento di Scienze Neurologiche, Neuropsicologiche, Morfologiche e Motorie, Università di Verona Dipartimento di Scienze Neurologiche, Neuropsicologiche, Morfologiche e Motorie, Università di Verona Department of Neurosciences, University of Florence Department of Neurosciences, University of Florence Parkinson Institute, Istituti Clinici di Perfezionamento, Milan, Italy Parkinson Institute, Istituti Clinici di Perfezionamento, Milan, Italy Dipartimento Scienze Neurologiche Università di Bologna Italy Cesa Lorella Maria Scaglione Dipartimento Scienze Neurologiche Università di Bologna Italy Aroldo Rossi Azienda Ospedaliera - Università di Perugia, Perugia (Italy) UN Author Proof Italian PR OO F Italian English language Nicola Tambasco Azienda Ospedaliera - Università di Perugia, Perugia (Italy) Gabriella Santangelo Department of Psychology, Second University of Naples, Caserta and IDC Hermitage Capodimonte, Naples Marina Picillo Department of Psychology, Second University of Naples, Caserta and IDC Hermitage Capodimonte, Naples Letterio Morgante Dipartimento di Neuroscienze, Scienze Psichiatriche ed Anestesiologiche, Universita’ di Messina 123 Journal : Large 10072 Dispatch : 12-5-2012 Pages : 5 Article No. : 1112 h LE 4 CP h h TYPESET 4 DISK h MS Code : NEUS2171 Neurol Sci Investigators Affiliation Francesca Morgante Dipartimento di Neuroscienze, Scienze Psichiatriche ed Anestesiologiche, Universita’ di Messina Neurology Unit University Hospital S.Annna Ferrara, Italy MariaChiara Sensi Neurology Unit University Hospital S.Annna Ferrara, Italy Manuela Pilleri Department for Parkinson disease, IRCCS San Camillo Venezia Roberta Biundo Department for Parkinson disease, IRCCS San Camillo Venezia Giampietro Nordera Casa di Cura Villa Margherita, Arcugnano (Vicenza) Italy Antonella Caria Casa di Cura Villa Margherita, Arcugnano (Vicenza) Italy Claudio Pacchetti Parkinson’s Dis. and Mov. Dis. Unit, Fondazione Istituto Neurologico Nazionale ‘‘C. Mondino’’, IRCCS, Roberta Zangaglia Parkinson’s Dis. and Mov. Dis. Unit, Fondazione Istituto Neurologico Nazionale ‘‘C. Mondino’’, IRCCS, PR OO F Rocco Quatrale Leonardo Lopiano Università degli Studi di Torino, Dipartimento di Neuroscienze, SCDU Neurologia 4 Maurizio Zibetti Università degli Studi di Torino, Dipartimento di Neuroscienze, SCDU Neurologia 4 Mario Zappia Dipartimento di Neuroscienze U.O.C. di Neurologia - Clinica Neurologica dell’Università degli Studi di Catania, Catania (Italy) Alessandra Nicoletti Dipartimento di Neuroscienze U.O.C. di Neurologia - Clinica Neurologica dell’Università degli Studi di Catania, Catania (Italy) Aldo Quattrone Dipartimento di Scienze Mediche dell’Università degli Studi Magna Graecia, Catanzaro Maria Salsone Dipartimento di Scienze Mediche dell’Università degli Studi Magna Graecia, Catanzaro Gianni Cossu S.C. di Neurologia - A.O. ‘‘G. Brotzu’’ Cagliari Daniela Murgia S.C. di Neurologia - A.O. ‘‘G. Brotzu’’ Cagliari Alberto Albanese Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano Francesca Del Sorbo Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano ED Author Proof Table 3 continued References 251 252 253 254 255 256 257 258 259 260 261 1. Fahn S, Elton RL. Unified Parkinson’s Disease Rating Scale. In: Recent developments in Parkinson’s disease: MacMillan Healthcare Information, 1987:153–164 2. Movement Disorder Society Task Force on Rating Scales for Parkinson’s Disease (2003) The Unified Parkinson’s Disease Rating Scale (UPDRS): status and recommendations. Mov Disord 18:738–750 3. Goetz CG, Tilley BC, Shaftman SR et al (2008) Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS): scale presentation and clinimetric testing results. Mov Disord 23:2129–2170 4. Goetz CG, Fahn S, Martinez-Martin P et al (2006) Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS): Process, format, and clinimetric testing plan. Mov Disord 22(1):41–47 5. Hatcher L (1994) A step-by-step approach to using the SAS system for factor analysis and structural equation modeling. SAS Institue, Cary 6. Gorsuch R (1983) Factor analysis, 2nd edn. Lawrence Erlbaum Associations, Hillsdale 7. Goetz CG, Stebbins GT, Chmura TA, Fahn S, Poewe W, Tanner CM (2010) Teaching program for the Movement Disorder Societysponsored revision of the Unified Parkinson’s Disease Rating Scale: (MDS-UPDRS). Mov Disord 25:1190–1194 UN CO RR E CT 250 249 123 Journal : Large 10072 Dispatch : 12-5-2012 Pages : 5 Article No. : 1112 h LE 4 CP h h TYPESET 4 DISK h MS Code : NEUS2171 262 263 264 265 266 267 268 269 270 271 272 273 274 275