Center of pressure-based balance evaluation in individuals with Parkinson’s disease: a reliability study

Abstract

ABSTRACT Objective The purpose of this study was to assess the test–retest reliability of different balance task outcomes, based on center of pressure (COP) measures in individuals with Parkinson’s disease. Method In this cross-sectional study, 19 older individuals with idiopathic Parkinson’s disease (seven females, 71 ± 7.8 years) performed a set of seven balance tasks on two occasions (a week apart) on an electronic force platform. Each set consisted of: 1) Bipedal; 2) Romberg with open eyes (OE); 3) Romberg with closed eyes (CE); 4) Tandem with OE; 5) Tandem with CE; 6) Tandem with OE using a dual task (DT) condition (simple mathematic operations concomitant with testing); and 7) One-leg stance, with the leg of preference over the force platform, with OE. The test–retest reliability of COP measures was tested using intraclass correlation coefficient (ICC) and Bland–Altman plots. Results The ICC results for the different tasks showed that the most reliable para- meters were derived from a 95% confidence ellipse around the COP and mean velocity, with the most reliable task being the Romberg with CE. Conclusions: We confirmed that balance based on COP measures was reliable in individuals with Parkinson’s disease, especially during the Romberg condition with closed eyes.