The effect of an alternative keyboard on musculoskeletal discomfort: A randomized cross-over trial

BACKGROUND: There is limited research on the effectiveness of alternative keyboards in reducing discomfort in the workplace. OBJECTIVE: We hypothesized that participants using a fixed split-angle (alternative) keyboard would report significantly greater improvements in discomfort in comparison to those using a standard keyboard. Additionally, we hypothesized that at 5 months participants would significantly prefer the configuration of the alternative keyboard in comparison to the standard keyboard. METHOD: In this randomized cross-over trial 77 symptomatic computer operators used fixed split-angle or standard flat keyboards for five months in their workplace, then switched to the other keyboard. Discomfort was collected weekly using the Weekly Discomfort Survey and usability was measured monthly. RESULTS: There was no significant keyboard by period effect on any discomfort measure. The number of participants with discomfort decreased dramatically in the first month of use, regardless of keyboard type, and this number remained relatively unchanged for the remainder of the study. Participants' ratings significantly favored the standard flat keyboard for usability. CONCLUSIONS: This study does not support the use of fixed split-angle keyboards over standard flat keyboards to reduce discomfort in the workplace. Further research is needed to evaluate if subgroups of keyboard users might benefit.