PEN-Ivory: the design and evaluation of a pen-based computer system for structured data entry.

PEN-Ivory is a pen-based computer system that uses structured data entry for creating patient progress notes. Users make simple gestures such as circles, lines, and scratch-outs to enter medical findings from a controlled vocabulary. The result of an interaction with PEN-Ivory is a computer-generated patient progress note in English prose. We designed PEN-Ivory's user interface in a principled way. We first created multiple working prototypes, each differing in one of three user-interface characteristics. Then we empirically evaluated the prototypes in a controlled, experimental setting for their efficiencies in enabling users to create patient progress notes. The prototype that allowed the fastest data entry had the following three user-interface characteristics: it used a paging form, used a fixed palette of modifiers, and made available all findings from the controlled vocabulary at once.