Dynamic documents are, in this paper, defined as single-page documents (paper- or screen-based), where the layout is fixed, but the content varies over time. A field study was conducted concerning the use of dynamic documents in the health care domain. The methods used were interviews, observations of work, and administration of simple reading tests with copies of authentic documents that were manipulated in various ways. Paper documents, as well as print-outs of screen displays, were used as originals. The results showed that experienced subjects had learned to recognise variations in features that were correlated to variations in content. The patterns formed by filled and unfilled fields in the paper documents were especially informative. Variations in this pattern could correctly be attributed to, for instance, variations in the condition of a patient.
The results were used to give a tentative description of general interaction with dynamic documents. Components of this interaction task could be grouped into identification, quality control and evaluation. A speculation is that, in parallel to the ordinary reading process, there is a number of automatic processes involved in the interaction. It was observed, that many components of interaction that seem to be perceived automatically in a paper-based setting, required attentional reading in a corresponding computerized setting. Because reading always requires consciously controlled processing, this probably accounted for the higher cognitive load that was experienced in interaction with the computerized documents. These assumptions have far reaching implications for user interface design and, therefore, call for further study.