Sampling frequency impacts measurement of walking activity after stroke

• DOI: 10.1682/jrrd.2012.12.0225
• Publication Date: 2013-12-18T19:54:06Z
• Authors: Brian Knarr; Margaret A. Roos; Darcy S. Reisman
• Keywords: Epoch (astronomy); Activity monitor; Stroke

The purpose of this study was to examine the effect sampling epoch on total time spent walking and number bouts per day in persons with stroke. Ninety-eight average age 63.8 yr poststroke 43.6 mo participated. Participants wore a StepWatch Activity Monitor for 3 5 consecutive days. strides taken collected s epochs down sampled into 10, 20, 30, 60 epochs. Total were determined each day. Low activity days defined as below 25th percentile steps high above 75th different (p < 0.001 all). resulted calculation ~40% ~6 times many epoch. Differences greater low Sampling affects daily step variables whose depends time, especially during must be carefully considered when designing studies aimed at understanding patterns activity.