The need for developing consensus-based guidelines in assessing Parkinson's disease laterality.

This study investigated the correlation between Parkinson's disease laterality, as defined by the Hoehn and Yahr (HY) scale, and appendicular parkinsonism scores from the MDS-UPDRS Part III using the PPMI dataset. While most cases (89.6 %) showed congruence, a 10.4 % discordance suggests that factors beyond appendicular parkinsonism influence clinical HY staging, highlighting a need for standardized guidelines.