title: A tool for measuring workers' sitting time by domain: the Workforce Sitting Questionnaire.
abstract: BACKGROUND
  Sitting time is an emerging health risk, and many working adults spend large amounts of time sitting each day. It is important to have reliable and accurate measurement tools to assess sitting time in different contexts.
  
  
  OBJECTIVE
  To validate the Workforce Sitting Questionnaire (WSQ), an adapted measure of total and domain-specific sitting time based on work and non-workdays for use in working adults.
  
  
  METHODS
  A convenience sample (N=95, 63.2% women) was recruited from two workplaces and by word-of-mouth in Sydney, Australia. Participants completed the WSQ, which asked about sitting time (1) while travelling to and from places; (2) while at work; (3) while watching TV; (4) while using a computer at home; and (5) while doing other leisure activities on work and non-workdays on two occasions, 7 days apart. Participants also wore an accelerometer for the 7 days between test and retest. They recorded the times they wore the accelerometer, the days they worked and their work times in a logbook. Analyses determined test-retest reliability with intraclass correlation coefficients (ICCs) and assessed criterion validity against accelerometers using Spearman's r and Bland-Altman plots.
  
  
  RESULTS
  Measuring total sitting time based on a workday, non-workday and on average had fair to excellent test-retest reliability (ICC=0.46-0.90) and had sufficient criterion validity against accelerometry in women (r=0.22-0.46) and men (r=0.18-0.29). Measuring domain-specific sitting at work on a workday was also reliable (ICC=0.63) and valid (r=0.45).
  
  
  CONCLUSIONS
  The WSQ has acceptable measurement properties for measuring sitting time at work on a workday and for assessing total sitting time based on work and non-workdays. This questionnaire would be suitable for use in research investigating the relationships between sitting time and health in working populations.
authors.affiliation: Prevention Research Collaboration, Sydney School of Public Health, University of Sydney, Level 2 Medical Foundation Building K25, Sydney, NSW 2006, Australia. josephine.chau@sydney.edu.au
authors.forename: Josephine Y
authors.initials: JY
authors.lastname: Chau
authors.forename: Hidde P
authors.initials: HP
authors.lastname: van der Ploeg
authors.forename: Scott
authors.initials: S
authors.lastname: Dunn
authors.forename: John
authors.initials: J
authors.lastname: Kurko
authors.forename: Adrian E
authors.initials: AE
authors.lastname: Bauman
mesh_terms: D000054:Acceleration; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods; D009517:New South Wales; D016272:Occupational Health; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D057185:Sedentary Behavior; D057566:Self Report; D011795:Surveys and Questionnaires / Q000592:standards*