title: Risk factors for the onset of nonspecific low back pain in office workers: a systematic review of prospective cohort studies.
abstract: OBJECTIVE
  The purpose of this study was to systematically review prospective cohort studies to identify risk factors for the onset of low back pain (LBP) in office workers.
  
  
  METHODS
  Online searches were conducted on PubMed, CINAHL Plus with full text, ScienceDirect, PEDro, ProQuest, and Scopus databases from 1980 to November 2011 using the following keywords: low back pain paired with risk or prognostic factors and office or computer or visual display unit (VDU) or visual display terminal (VDT). The methodological quality of each study was assessed using a 21-item checklist, which was divided into 2 parts: the internal validity (11 items) and descriptive quality (10 items) of studies. Strength of evidence for risk factors associated with the development of nonspecific LBP was assessed by defining 5 levels of evidence based on the number of studies and the quality score of studies.
  
  
  RESULTS
  Eighteen full-text articles were identified, and 15 were excluded. A total of 3 articles were judged to meet the selection criteria and were included in the methodological quality assessment. Risk factors were divided into 3 groups: individual, work-related physical, and work-related psychosocial risk factors. There was strong evidence that history of LBP is a predictor of the onset of LBP. Limited evidence was found that the combination of postural risk factors and job strain is associated with the onset of LBP.
  
  
  CONCLUSIONS
  After review of 3 high-quality prospective studies on the association between risk factors and the onset of nonspecific LBP in office workers, few risk factors were found to predict the onset of LBP in office workers.
authors.affiliation: Department of Physical Therapy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand. prawit.j@chula.ac.th
authors.forename: Prawit
authors.initials: P
authors.lastname: Janwantanakul
authors.forename: Ekalak
authors.initials: E
authors.lastname: Sitthipornvorakul
authors.forename: Arpalak
authors.initials: A
authors.lastname: Paksaichol
mesh_terms: D015331:Cohort Studies; D003201:Computers; D006801:Humans; D017116:Low Back Pain / Q000209:etiology*; D009784:Occupational Diseases / Q000209:etiology*; D011446:Prospective Studies; D012307:Risk Factors