Preliminary investigation of test-retest reliability of a robotic assessment for Parkinson's disease

Several systems have been proposed to objectively quantify the motor signs of Parkinson's disease. While validity has been investigated for a subset of these systems, test-retest reliability of automated assessments has been more neglected. We have created a protocol that uses a robotic system to measure force and position as the user performs tracking tasks with and without a simultaneous cognitive or motor task. We present preliminary results for test-retest reliability with eight individuals with early to moderate PD. Based on this data, we identified variables with large, significant correlations between the test and retest data. A total of 21 reliable variables were identified with all portions of the assessment protocol producing reliable variables.