title: Validity of Questionnaire and Representativeness of Objective Methods for Measurements of Mechanical Exposures in Construction and Health Care Work.
abstract: OBJECTIVE
  To determine the criterion validity of a questionnaire on physical exposures compared to objective measurements at construction and health care sites and to examine exposure variation over several working days.
  
  
  METHODS
  Five hundred ninety-four construction and health care workers answered a baseline questionnaire. The daily activities (standing, moving, sitting, number of steps), postures (inclination of the arm and the trunk), and relative heart rate of 125 participants were recorded continuously over 3-4 working days. At the end of the first measurement day, the participants answered a second questionnaire (workday questionnaire).
  
  
  RESULTS
  All objective activity measurements had significant correlations to their respective questions. Among health care workers, there were no correlations between postures and relative heart rate and the baseline questionnaire. The questionnaires overestimated the exposure durations. The highest explained variance in the adjusted models with self-reported variables were found for objectively measured sitting (R2 = 0.559) and arm inclination > 60° (R2 = 0.420). Objective measurements over several days showed a higher reliability compared to single day measurements.
  
  
  CONCLUSIONS
  Questionnaires cannot provide an accurate description of mechanical exposures. Objective measurements over several days are recommended in occupations with varying tasks.
authors.affiliation: Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Markus
authors.initials: M
authors.lastname: Koch
authors.affiliation: Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Lars-Kristian
authors.initials: LK
authors.lastname: Lunde
authors.affiliation: Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway.|Oslo University Hospital, Oslo, Norway.
authors.forename: Tonje
authors.initials: T
authors.lastname: Gjulem
authors.affiliation: Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Stein
authors.initials: S
authors.lastname: Knardahl
authors.affiliation: Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway.
authors.forename: Kaj Bo
authors.initials: KB
authors.lastname: Veiersted
mesh_terms: D000328:Adult; D060389:Construction Industry; D005260:Female; D006282:Health Personnel; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000175:diagnosis / Q000503:physiopathology; D009784:Occupational Diseases / Q000175:diagnosis / Q000503:physiopathology; D016272:Occupational Health / Q000706:statistics & numerical data; D009790:Occupations / Q000145:classification; D011187:Posture / Q000502:physiology*; D012044:Regression Analysis; D015203:Reproducibility of Results; D057566:Self Report; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D011795:Surveys and Questionnaires / Q000592:standards*