title: The Effectiveness of a Web-Based Computer-Tailored Intervention on Workplace Sitting: A Randomized Controlled Trial.
abstract: BACKGROUND
  Effective interventions to influence workplace sitting are needed, as office-based workers demonstrate high levels of continued sitting, and sitting too much is associated with adverse health effects. Therefore, we developed a theory-driven, Web-based, interactive, computer-tailored intervention aimed at reducing and interrupting sitting at work.
  
  
  OBJECTIVE
  The objective of our study was to investigate the effects of this intervention on objectively measured sitting time, standing time, and breaks from sitting, as well as self-reported context-specific sitting among Flemish employees in a field-based approach.
  
  
  METHODS
  Employees (n=213) participated in a 3-group randomized controlled trial that assessed outcomes at baseline, 1-month follow-up, and 3-month follow-up through self-reports. A subsample (n=122) were willing to wear an activity monitor (activPAL) from Monday to Friday. The tailored group received an automated Web-based, computer-tailored intervention including personalized feedback and tips on how to reduce or interrupt workplace sitting. The generic group received an automated Web-based generic advice with tips. The control group was a wait-list control condition, initially receiving no intervention. Intervention effects were tested with repeated-measures multivariate analysis of variance.
  
  
  RESULTS
  The tailored intervention was successful in decreasing self-reported total workday sitting (time × group: P<.001), sitting at work (time × group: P<.001), and leisure time sitting (time × group: P=.03), and in increasing objectively measured breaks at work (time × group: P=.07); this was not the case in the other conditions. The changes in self-reported total nonworkday sitting, sitting during transport, television viewing, and personal computer use, objectively measured total sitting time, and sitting and standing time at work did not differ between conditions.
  
  
  CONCLUSIONS
  Our results point out the significance of computer tailoring for sedentary behavior and its potential use in public health promotion, as the effects of the tailored condition were superior to the generic and control conditions.
  
  
  BACKGROUND
  Clinicaltrials.gov NCT02672215; http://clinicaltrials.gov/ct2/show/NCT02672215 (Archived by WebCite at http://www.webcitation.org/6glPFBLWv).
authors.affiliation: Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium. Katrien.DeCocker@ugent.be.
authors.forename: Katrien
authors.identifier: http://orcid.org/0000-0001-7510-4419
authors.initials: K
authors.lastname: De Cocker
authors.forename: Ilse
authors.identifier: http://orcid.org/0000-0001-9969-7597
authors.initials: I
authors.lastname: De Bourdeaudhuij
authors.forename: Greet
authors.identifier: http://orcid.org/0000-0003-4983-6557
authors.initials: G
authors.lastname: Cardon
authors.forename: Corneel
authors.identifier: http://orcid.org/0000-0002-4445-8094
authors.initials: C
authors.lastname: Vandelanotte
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001331:Automation; D003201:Computers / Q000706:statistics & numerical data; D005246:Feedback; D005260:Female; D006293:Health Promotion / Q000379:methods*; D006801:Humans; D020407:Internet; D008297:Male; D011187:Posture; D011998:Recreation; D057185:Sedentary Behavior; D057566:Self Report; D013997:Time Factors; D014850:Waiting Lists; D017132:Workplace
keywords: activPAL; computer tailoring; employees; randomized controlled trial; sedentary behavior; sitting time