A Scientometric Analysis of Bias and Fairness in Parkinson's Disease Clinical Assessment Scales

Background: Clinical assessment scales are fundamental tools for evaluating Parkinson's disease (PD), yet potential biases in their development and validation may compromise their fairness across diverse populations. Objective: This study aimed to conduct a comprehensive scientometric analysis of bias and fairness in PD clinical assessment scales by examining demographic representation, geographic distribution, and methodological biases in the foundational literature. Methods: Following PRISMA guidelines, we systematically searched five databases (PubMed, Embase, Medline and Central) from inception to 2024. Studies included if they validated or developed PD assessment scales including UPDRS, MDS-UPDRS, MoCA, or MMSE. Data extraction focused on 17 predefined bias domains including demographic representation, geographic distribution, and methodological considerations. Bibliometric analysis was performed using Python 3.12 and Tableau Public. Results: From 3,836 initially identified studies, 109 met inclusion criteria, encompassing 655 authors across 34 countries and 47 journals. Geographic analysis revealed stark disparities: high-income countries contributed 99 publications (90.8%), while low/middle-income countries contributed only 10 publications (9.2%). Europe dominated with 48 publications (44.0%), followed by North America with 39 publications (35.8%). Critical bias domains showed concerning gaps: only 8 studies (7.3%) captured race/ethnicity data, 13 studies (11.9%) adjusted cognitive tests for education, and zero studies addressed digital literacy barriers. Female authorship remained underrepresented at 36.6% overall, with particularly low representation in senior positions (37.1% of last authors) versus 44 male authors (62.9%). Conclusions: This scientometric analysis provides robust evidence of persistent geographic, demographic, and methodological biases in PD assessment scale research, potentially compromising their fairness across diverse populations. Our findings highlight the urgent need for more inclusive research practices, culturally sensitive adaptations of existing scales, and development of novel assessment approaches that account for demographic and geographic diversity to ensure equitable clinical evaluation of PD patients worldwide.