Estimated and experienced subjective assessment of the ergonomic quality of a keyboard

At an ergonomically optimized VDU-workstation, a group of 10 test subjects (Ss) carried out a typing task both at the test keyboard and a reference computer keyboard. The participants’ personal subjective assessments concerning the working conditions with the two keyboards and the layout of the ergonomic model were recorded via specially designed questionnaires. These were given prior to, and after, the working tests and, therefore, reflected ratings without and with working experience. The posture of the hand, the lower and the upper arm, and the shoulder during text input were evaluated quite differently as a consequence of using the two keyboards. The working posture associated with the conventional keyboard was never assessed positively. The ratings always reached positive values when operating the ergonomic model. The handling of the keyboard and the overall impression were also in favor of the test keyboard as a result of the working tests. Comfort and effort while typing at the keyboards also differed substantially and were in favor of the test keyboard. The same was true for altogether 10 items of the questionnaire, aiming at evaluation of details of the ergonomic keyboard and its overall appearance.