JMIR Publications

ABSTRACT

Background:

An enhanced understanding of Parkinson’s disease (PD) in recent years has led to the revelation that the motor symptoms by which we’ve been defining and describing PD are late-stage, downstream consequences of a degenerative process decades in the making. The objective outcome measures traditionally used in clinic and PD research rely heavily on motor symptoms and have been shown to lack sensitivity early in the disease. The Patient-Reported Outcomes in PD (PRO-PD) scale is an entirely subjective, patient-centered tool designed to be useful to patients, providers, and researchers as a remote patient monitoring system.

Objective:

The goal was to create a continuous outcome measure that does not require a clinic visit, is sensitive early in the disease, does not fluctuate throughout the day, captures severity of both motor and non-motor symptoms, and correlates with quality of life (QoL) and existing measures of severity.

Methods:

Two datasets were used with a total of 13,349 participants with PRO-PD scores. Data quality, feasibility, Cronbach’s alpha, and confirmatory factor analysis was conducted. Longitudinal analysis to determine change over time was completed. Response to change was evaluated by initiation of levodopa.

Results:

The PRO-PD scale shows acceptable validity with a 95.1% completion rate, non-significant floor and ceiling effects, acceptable skew and kurtosis, Cronbach’s alpha of >0.75 for the total scale and subscales with acceptable unidimentionality (r between 0.37 and 0.84). Confirmatory factor analysis (CFI = 0.841, Tucker Lewis Index = 0.829, SRMSEA = 0.054) shows room for improvement for factors. Responsiveness has been shown by mean change per year in PRO-PD score of 38 (±14) and significant improvement in PRO-PD score with initiation of dopamine replacement therapy.

Conclusions:

These analyses suggest the PRO-PD is a feasible and valid tool for remote patient monitoring in PD.