Accuracy of consumer-based activity trackers as measuring tool and coaching device in patients with COPD and healthy controls

The aim of this study is to investigate the accuracy of two consumer-based activity trackers (i.e. Fitbit Zip, worn at the hip and Fitbit Alta, worn at the wrist) in patients with COPD and healthy age-matched controls, 1) to measure the PA of a patient (‘accuracy as a measuring tool’); and 2) to distinguish more and less active days at an individual level (‘validity as a coaching tool’), as compared to a validated activity monitor (i.e. Dynaport Movemonitor)