Errors in measurement of +G(z) acceleration tolerance

David Ludwig, L. P. Krock

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Most accleration studies estimate a subject's G-level tolerance by taking only one determination (test) for a given condition. The purpose of this study was to examine the error structure and reliability of an individual's acceleration tolerance and to provide design considerations for future experimentation. A hierarchical (nested) design was used to estimate the sources of variation in measuring G-level tolerance. Six males rode relaxed in the USAF School of Aerospace Medicine human-use centrifuge and were exposed to a 0.1 G/s onset rate profile until greyout. Each subject was tested on three randomly selected days with three repeated determinations within a day. This design allowed for an estimate of both day-to-day and measurement error within a testing session. A single +Gz tolerance determination was found to be moderately unreliable (reliability coefficient = 0.74). Under the best of circumstances a subject's G-level tolerance cannot be estimated with any more accuracy than about ± 0.3 G with 95% confidence. This degree of accuracy can only be obtained with multiple measurements.

Original languageEnglish
Pages (from-to)261-265
Number of pages5
JournalAviation Space and Environmental Medicine
Volume62
Issue number3
StatePublished - Mar 21 1991
Externally publishedYes

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Aerospace Medicine
Centrifuges
Measurement errors
Medicine
Testing

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Pollution
  • Medicine(all)

Cite this

Errors in measurement of +G(z) acceleration tolerance. / Ludwig, David; Krock, L. P.

In: Aviation Space and Environmental Medicine, Vol. 62, No. 3, 21.03.1991, p. 261-265.

Research output: Contribution to journalArticle

Ludwig, David ; Krock, L. P. / Errors in measurement of +G(z) acceleration tolerance. In: Aviation Space and Environmental Medicine. 1991 ; Vol. 62, No. 3. pp. 261-265.
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