Pain characteristics of Parkinson's disease using validated Arabic versions of the King's Parkinson's Disease Pain Scale and Questionnaire: A Multicenter Egyptian Study.

Objective: Pain is one of the most common non-motor symptoms in Parkinson's disease (PD), with variable characteristics among populations. This multicenter Egyptian study aimed to translate and validate the King's Parkinson's Disease Pain Scale (KPPS) and questionnaire (KPPQ) into Arabic versions and to investigate the pain characteristics in Egyptian people with PD (PWP). Methods: 192 PWP and 100 sex and age-matched controls were evaluated by KPPS-Arabic and KPPQ-Arabic. Both tools were assessed for test-retest reliability, floor or ceiling effects, construct validity and convert validity. PWP were assessed also by MDS-UPDRS, Hoehn and Yahr, NMSS, PD Questionnaire-39, and the Non-Motor Fluctuation Assessment (NoMoFA). Results: KPPS-Arabic and KPPQ-Arabic showed inter and intra-rater consistency and high validity, with an acceptable ceiling effect. 188 PWP (97.9%) reported at least 1 type of pain, (p<0.001). The severity and prevalence of KPPS-Arabic domains were significantly higher in all pain domains among PWP compared to controls (p < 0.001). Fluctuation-related and musculoskeletal pains were the most common (81.3% and 80.7%, respectively). In the PD group, the total and domains of KPPS-Arabic were significantly correlated to the MDS-UPDRS total, parts I, II, III, PIGD, axial, and H &Y scores, but not age or age of onset. Predictors of KPPS-Arabic included the total MDS-UPDRS, part III-Off, disease duration, total NMSS, and NoMoFA. Conclusion: The current multicentre study provided a validated Arabic versions of KPPS and KPPQ, with high reliability and validity, and demonstrated a high prevalence and severity of pain within Egyptian PWP and characterized its determinants.

Validation of the Arabic Version of the Movement Disorder Society-Unified Parkinson's Disease Rating Scale.

BACKGROUND: The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) has become the gold standard for evaluating different domains in Parkinson's disease (PD), and it is commonly used in clinical practice, research, and clinical trials. OBJECTIVES: The objectives are to validate the Arabic-translated version of the MDS-UPDRS and to assess its factor structure compared with the English version. METHODS: The study was carried out in three phases: first, the English version of the MDS-UPDRS was translated into Arabic and subsequently back-translated into English by independent translation team; second, cognitive pretesting of selected items was performed; third, the Arabic version was tested in over 400 native Arabic-speaking PD patients. The psychometric properties of the translated version were analyzed using confirmatory factor analysis (CFA) as well as exploratory factor analysis (EFA). RESULTS: The factor structure of the Arabic version was consistent with that of the English version based on the high CFIs for all four parts of the MDS-UPDRS in the CFA (CFI ≥0.90), confirming its suitability for use in Arabic. CONCLUSIONS: The Arabic version of the MDS-UPDRS has good construct validity in Arabic-speaking patients with PD and has been thereby designated as an official MDS-UPDRS version. The data collection methodology among Arabic-speaking countries across two continents of Asia and Africa provides a roadmap for validating additional MDS rating scale initiatives and is strong evidence that underserved regions can be energically mobilized to promote efforts that apply to better clinical care, education, and research for PD. © 2022 International Parkinson and Movement Disorder Society.