Objectives This study attempted to determine whether the current “one-size-fits-all” paradigm used for computer input devices meets the needs of the current computer-using population.

Methods Wrist posture and muscle activity in the flexor digitorum superficialis and extensor digitorum communis muscles were measured and compared between 14 children (ages 5 to 8 years) and their same-gender biological parents. The participants performed a standardized mousing task with a standard and child-proportional mouse. The literature on finger anthropometry was systematically reviewed to determine finger size variation as a function of age, size percentile (5th, 50th, 95th), and gender and its influence on the design of computer input devices.

Results With the standard mouse, the children used a greater [18.4 (SD 11.3) degrees] ulnar deviation and less [9.4 (SD 12.9) degrees] extension than their adult counterparts. With the child-proportional devices, their ulnar deviation [4.0 (SD 6.4) degrees, P=0.04] was significantly reduced, as was their forearm muscle activity (P

Key terms anthropometric difference; anthropometry; child; children; computer; computer input device; computer keyboard; computer mouse; exposure; gender; woman