An on going study that demonstrates that the results of a single outcome study cannot be conclusive. For example, an intervention that puts wrist posture in a more neutral position may not be the right thing to do if it also increases shoulder muscle loads. Several studies have investigated computer key switch forces applied, individual work style, fatigue and other factors. These studies significantly advanced the understanding of key biomechanics. They found that key switch design does affect force applied but individual work style has a much greater influence.
Typists strike the keys with four to seven times the force necessary.
Other studies have investigated muscle fatigue while mousing, how pointing devices are being used in field environments identifying distinct basic joint movements, patterns of use, gripping styles and other factors. An on going study is investigating the effect of key damping on key force applied. This is a new area of investigation. Ergonomic Implications of Portable Computers An on going pilot study to develop tools and a methodology to assess notebook personal computer patterns of use and to test them with a diverse sample of professionals. A survey is underway to describe the impact of portable computers and other emerging technologies on a sample of U.S. organizations .