Systematic review: height-adjustable workstations to reduce sedentary behaviour in office-based workers.

BACKGROUND Time spent sitting in the workplace is an important contributor to overall sedentary risk. Installation of height-adjustable workstations has been proposed as a feasible approach for reducing occupational sitting time in office workers. AIMS To provide an accurate overview of the controlled trials that have evaluated the effects of height-adjustable workstation interventions on workplace sitting time in office-based workers. METHODS A comprehensive search was conducted up until March 2014 in the following databases: Medline, PsychINFO, CENTRAL, EMBASE and PEDro. To identify unpublished studies and grey literature, the reference lists of relevant official or scientific web pages were also checked. Studies assessing the effectiveness of height-adjustable workstations using a randomized or non-randomized controlled design were included. RESULTS The initial search yielded a total of 8497 citations. After a thorough selection process, five studies were included with 172 participants. A formal quality assessment indicated that risk of bias was high in all studies and heterogeneity in interventions and outcomes prevented meta-analysis. Nevertheless, all studies reported that height-adjustable workstation interventions reduced occupational sitting time in office workers. There was insufficient evidence to determine effects on other relevant health outcomes (e.g. body composition, musculoskeletal symptoms, mental health). CONCLUSIONS There is insufficient evidence to make firm conclusions regarding the effects of installing height-adjustable workstations on sedentary behaviour and associated health outcomes in office workers. Larger and longer term controlled studies are needed, which include more representative populations.