title: Sampling duration effects on centre of pressure descriptive measures.
abstract: The different measures used to characterize postural sway are sensitive to variations in sampling duration, yet there remains marked variability and a lack of consistency in this temporal parameter when compared between studies. We investigated the effect of sampling duration on 22 commonly used frequency and time domain measures and stabilogram diffusion coefficients. Participants stood quietly on a forceplate during two 600s standing trials with eyes open and eyes closed. The results clearly show that the amplitudes of the descriptive measures are sensitive to sampling duration. Only measures related to the amount of sway were sensitive for eyes open versus eyes closed conditions. In addition to sample duration, the filter settings, sampling frequency and fitting windows should be standardized since they also affect the magnitude of the descriptive measures. Without such standards, the inability to accurately compare between studies will persist.
authors.affiliation: Department of Biomechanical Engineering, Institute of Biomedical Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands; Department of Biomechanical Engineering, 3ME faculty, Delft University of Technology, Mekelweg 2, 2628 Delft, The Netherlands. H.vanderKooij@utwente.nl
authors.forename: Herman
authors.initials: H
authors.lastname: van der Kooij
authors.forename: Adam D
authors.initials: AD
authors.lastname: Campbell
authors.forename: Mark G
authors.initials: MG
authors.lastname: Carpenter
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D011312:Pressure; D011434:Proprioception; D012680:Sensitivity and Specificity; D013997:Time Factors