Figure 2 Peak force changes in size of target icons
In terms of the risk of musculoskeletal disorders, the most forceful motion was observed when subjects used drag motions to point the smallest target. Apparently, this type of task is frequently experienced in operating graphical packages. Some GUI design consideration may be applied for reducing such risks effectively. For example, the effective pointing area should be enlarged for not only reducing the risk of pointing errors but also reducing such forceful motions. Also, providing a priori-visual feedback to show the effective area for dragging before pressing the mouse button may be useful to realize whether or not the users can proceed drag motions before they start the rubber-banding task.
In summary, mouse operating force during various mouse actions and target icon size differed substantially. Combined with operating posture and repetitiveness of the task, the quantitative and long-term study of mouse operations should be concerned to fully analyze the epidemiological risk of musculoskeletal disorders during mouse operations.
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