title: Effectiveness of a feedback signal in a computer mouse on upper extremity musculoskeletal symptoms: a randomised controlled trial with an 8-month follow-up.
abstract: OBJECTIVE
  To study the effectiveness of using a computer mouse with a feedback signal for upper extremity musculoskeletal symptoms in office workers.
  
  
  METHODS
  A randomised controlled trial with 8 months of follow-up was carried out. The intervention consisted of a computer mouse with a feedback signal. In total, 354 subjects were allocated to the intervention group or the control group. Measurements were performed with electronic questionnaires at baseline, after 4 months and after 8 months. Outcome variables were the prevalence and incidence of upper extremity musculoskeletal symptoms and disability in the upper extremities. The intervention process was evaluated by software registration.
  
  
  RESULTS
  The use of the mouse with a feedback signal resulted in a significant decrease in duration of mouse usage over time. No differences were found in the number of mouse usage rest breaks. No differences were found in the prevalence (p = 0.29) or incidence (p = 0.832) of upper extremity musculoskeletal symptoms between the groups 8 months after baseline. The prevalence decreased from 49% at baseline to 44% after 8 months in the control group, while it remained at 36% in the intervention group. The incidence was 21% in the control group and 22% in the intervention group. Among the population with upper extremity musculoskeletal symptoms at baseline, the risk of experiencing symptoms after 8 months did not differ between the groups (p = 0.49). Minor disability was found in both groups. In the intervention group, a lower level of physical disability over time was reported than in the control group (p = 0.02).
  
  
  CONCLUSIONS
  A feedback signal computer mouse does not affect the prevalence and incidence of upper extremity musculoskeletal symptoms, but it does lower disability scores. Given the high prevalence, studying preventive interventions for upper extremity musculoskeletal symptoms is of high importance.
  
  
  BACKGROUND
  ISRCTN13222474.
authors.affiliation: Academic Medical Center, University of Amsterdam, Coronel Institute of Occupational Health, the Netherlands.
authors.forename: E M
authors.initials: EM
authors.lastname: Meijer
authors.forename: J K
authors.initials: JK
authors.lastname: Sluiter
authors.forename: M H W
authors.initials: MH
authors.lastname: Frings-Dresen
mesh_terms: D000328:Adult; D016287:Computer Peripherals; D003201:Computers; D005246:Feedback; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009140:Musculoskeletal Diseases / Q000453:epidemiology* / Q000517:prevention & control; D009426:Netherlands / Q000453:epidemiology; D009784:Occupational Diseases / Q000453:epidemiology* / Q000517:prevention & control; D016273:Occupational Exposure / Q000009:adverse effects*; D015995:Prevalence; D034941:Upper Extremity / Q000293:injuries*; D014940:Work Schedule Tolerance