title: Quantifying time awake posturographically.
abstract: Although sleepiness is a major risk factor in traffic and occupational accidents, convenient, quantitative, and commercial sleepiness testing is lacking. The issue is relevant to policymakers concerned with legislation for, and surveillance of, traffic- and occupational safety. This work suggested and examined posturographic sleepiness testing for instrumentation purposes. In 63 subjects--for whom we tested balance with a force platform during sustained waking for maximum 36 h--sustained waking impaired the balance. The sustained waking explained 60% of the diurnal balance variations, whereas the time of day explained 40% of the balance variations. The first finding -that balance depends on the subject's time awake (TA)- allowed to posturographically estimate the subjects' TA with 86% accuracy and 97% precision. Results also show that balance scores tested at 13:30 hours serve as a threshold to detect excessive sleepiness. This work provides guidelines for a posturographic sleepiness tester.
authors.affiliation: Finnish Institute of Occupational Health, FIN-00250 Helsinki, Finland. pia.forsman@ttl.fi
authors.forename: P
authors.initials: P
authors.lastname: Forsman
authors.forename: A
authors.initials: A
authors.lastname: Wallin
authors.forename: A
authors.initials: A
authors.lastname: Tietäväinen
authors.forename: E
authors.initials: E
authors.lastname: Haeggström
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D010808:Physical Examination / Q000379:methods*; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology*; D012894:Sleep Stages / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*; D055815:Young Adult