title: Computer use and carpal tunnel syndrome: A meta-analysis.
abstract: BACKGROUND
  Studies have reported contradictory results on the role of keyboard or mouse use in carpal tunnel syndrome (CTS). This meta-analysis aimed to assess whether computer use causes CTS.
  
  
  METHODS
  Literature searches were conducted in several databases until May 2014. Twelve studies qualified for a random-effects meta-analysis. Heterogeneity and publication bias were assessed.
  
  
  RESULTS
  In a meta-analysis of six studies (N=4964) that compared computer workers with the general population or other occupational populations, computer/typewriter use (pooled odds ratio (OR)=0.72, 95% confidence interval (CI) 0.58-0.90), computer/typewriter use ≥1 vs. <1h/day (OR=0.63, 95% CI 0.38-1.04) and computer/typewriter use ≥4 vs. <4h/day (OR=0.68, 95% CI 0.54-0.87) were inversely associated with CTS. Conversely, in a meta-analysis of six studies (N=5202) conducted among office workers, CTS was positively associated with computer/typewriter use (pooled OR=1.34, 95% CI 1.08-1.65), mouse use (OR=1.93, 95% CI 1.43-2.61), frequent computer use (OR=1.89, 95% CI 1.15-3.09), frequent mouse use (OR=1.84, 95% CI 1.18-2.87) and with years of computer work (OR=1.92, 95% CI 1.17-3.17 for long vs. short). There was no evidence of publication bias for both types of studies.
  
  
  CONCLUSIONS
  Studies that compared computer workers with the general population or several occupational groups did not control their estimates for occupational risk factors. Thus, office workers with no or little computer use are a more appropriate comparison group than the general population or several occupational groups. This meta-analysis suggests that excessive computer use, particularly mouse usage might be a minor occupational risk factor for CTS. Further prospective studies among office workers with objectively assessed keyboard and mouse use, and CTS symptoms or signs confirmed by a nerve conduction study are needed.
authors.affiliation: Centre of Expertise for Health and Work Ability, and Disability Prevention Centre, Finnish Institute of Occupational Health, Helsinki, Finland. Electronic address: rahman.shiri@ttl.fi.
authors.forename: Rahman
authors.initials: R
authors.lastname: Shiri
authors.affiliation: Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Canada.
authors.forename: Kobra
authors.initials: K
authors.lastname: Falah-Hassani
mesh_terms: D002349:Carpal Tunnel Syndrome / Q000453:epidemiology / Q000209:etiology*; D016287:Computer Peripherals / Q000706:statistics & numerical data; D003201:Computers / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D009784:Occupational Diseases / Q000209:etiology* / Q000517:prevention & control; D012307:Risk Factors
keywords: Carpal tunnel syndrome; Computers; Keyboard; Median nerve; Occupations; Typewriter