A preliminary study evaluating the concurrent validity of a waist worn and a wrist worn ActiGraph - during free-living activities in people with Parkinson's disease over a seven day period.

Abstract

Background: Parkinson's disease (PD) is one of the most prevalent neurological conditions within the aging population. One of the symptoms of PD is the decline in physical activity and an increase in sedentary behaviour. It is essential to monitor activity within this population as exercise is recognised to slow the process of the disease. Therefore it is essential to have valid tools to measure sedentary behaviour within this population. Objective: Establish the concurrent validity between an ActiGraph worn on the waist and worn on the wrist. Participants: 9 participants were recruited (7 males and 2 females). All had a confirmed diagnosis of Parkinson's, a Hoehn and Yahr rating of 3 or less and an MMSE of 28 or above. Methods: Participants wore two ActiGraphs, one on their non-dominant wrist and one on their left hip for 7 days during free living. Data collected from the devices was analysed and comparisons were made between the sedentary time recorded on the waist and on the wrist. Results: There was a strong correlation between the devices (0.7 and 0.72), daily sedentary and weekly sedentary behaviour respectively. However the bias between the devices was considerably high at 24.43, 24.96 respectively. Conclusion: Further research is needed to conclude the concurrent validity between the devices. The wrist worn device needs more testing to test appropriateness for this population. Therefore, at present it could be suggested to wear the waist worn ActiGraph when evaluating sedentary behaviour within this population.