Effects of a Chair-Mounted Split Keyboard on Performance, Posture and Comfort

Abstract

In a repeated measures experiment, twelve female typists performed typing and cursor positioning tasks using a chair-mounted split keyboard (FAK) and a conventional keyboard (CK) on an articulated tray. Results showed that the FAK significantly reduced ulnar deviation, but did not reduce wrist extension compared with the CK arrangement. Typing speed was slower for the FAK than the CK, but accuracy was unaffected. Videomotion analysis showed that more subjects sat fully back in their chair with their shoulders relaxed and their hands in less ulnar deviation when using the FAK to type. Other postural changes are described. Subjective comfort and strain ratings are described. Results are discussed within the limitations of a short-term laboratory study.