Comparison of self and proxy ratings for motor performance of individuals with Parkinson disease

The impact of Parkinson disease (PD) has been examined in recent years by comparing self-ratings by individuals with PD and proxy ratings by caregivers, communication partners, and/or health care providers. However, the existing evidence is mixed with some researchers suggesting perfect agreement between rater groups while others suggesting differences among rater groups for motor performance of individuals with PD. The current study examined self and proxy perception of performance of individuals with PD for six motor characteristics (gait, rigidity, right and left bradykinesia, rest tremors, and perception of physical effort) based on Unified Parkinson Disease Rating Scale (UPDRS) motor tasks. Participants included 20 individuals with PD, 20 communication partners, and a trained rater. The study compared perceptual ratings and corresponding UPDRS scores as well as rater group differences for perceptual motor ratings. A series of Pearson Product Moment Correlations indicated significant relationship only between self-ratings for gait and rest tremors by individuals with PD and corresponding UPDRS scores (p<.05). Further, a multivariate analysis of variance was completed to compare rater group differences. Results indicated significant overestimation of rest tremors by both individuals with PD and communication partners when compared to corresponding ratings by the trained rater. Overall, the study provided evidence for perception deficits among individuals with PD and communication partners regarding motor performance of individuals with PD. Additional studies are needed to further explore the changes in perception abilities of individuals with PD and communication partners with respect to disease duration, disease severity, and other co-morbid factors.