title: Actigraphy in older adults: comparison of means and variability of three different aggregates of measurement.
abstract: Actigraphy has emerged as a valuable method for measuring natural sleep patterns; however, it is unclear how many consecutive nights should be measured and what sleep parameter values are typical of older adults. This study examined sleep in relatively healthy community-based older adults for 14 consecutive days. The findings present comparison values for Actiwatch-L actigraphy in older adults, and can be used to determine an appropriate length of measurement. When using means of the aggregate period, a 3-day aggregate is comparable to the values obtained over 7- or 14-day aggregates. However, if variability of the sleep parameter is of interest, a minimum of a 7-day aggregate is needed, and 14-day aggregates are better when measuring sleep onset latency.
authors.affiliation: Department of Adult and Elderly Nursing, University of Florida, College of Nursing, Gainesville, FL 32606, USA. mrowe@ufl.edu
authors.forename: Meredeth
authors.initials: M
authors.lastname: Rowe
authors.forename: Christina
authors.initials: C
authors.lastname: McCrae
authors.forename: Judy
authors.initials: J
authors.lastname: Campbell
authors.forename: Claydell
authors.initials: C
authors.lastname: Horne
authors.forename: Tom
authors.initials: T
authors.lastname: Tiegs
authors.forename: Brandy
authors.initials: B
authors.lastname: Lehman
authors.forename: Jing
authors.initials: J
authors.lastname: Cheng
mesh_terms: D000367:Age Factors; D000368:Aged; D004594:Electrophysiology / Q000295:instrumentation; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D017286:Polysomnography / Q000295:instrumentation*; D012016:Reference Values; D015203:Reproducibility of Results; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages; D012893:Sleep Wake Disorders / Q000175:diagnosis; D014851:Wakefulness / Q000502:physiology*