The MDS-UPDRS (Movement Disorder Society-Unified Parkinson’s Disease Rating Scale) became the gold standard for evaluating distinct domains in Parkinson’s disease (PD) and was widely used in clinical practice, research, and clinical trials. For a study, researchers sought to verify the Arabic-translated version of the MDS-UPDRS and compare it to the English version in terms of factor structure.

The study was conducted in three phases: first, the MDS-UPDRS was translated into Arabic and then back into English by an independent translation team; second, cognitive pretesting of selected items was conducted; and third, the Arabic version was tested in over 400 native Arabic-speaking PD patients. Confirmatory component analysis (CFA) and exploratory factor analysis were used to assess the psychometric features of the translated version (EFA). 

Based on the high CFIs for all four elements of the MDS-UPDRS in the CFA (CFI 0.90), the Arabic version’s factor structure was consistent with that of the English version, demonstrating its acceptability for usage in Arabic. The Arabic version of the MDS-UPDRS has been certified as an official MDS-UPDRS version because to its high construct validity in Arabic-speaking patients with Parkinson’s disease. The data collection methodology used among Arabic-speaking countries on two continents, Asia and Africa, provided a roadmap for validating additional MDS rating scale initiatives and was strong evidence that underserved regions could be energetically mobilized to promote efforts that apply to better clinical care, education, and research for Parkinson’s disease.