This study is part of research that is investigating the notion that human performance in dynamic and intentional decision making environments, such as ambulance dispatch management, can be improved if information is portrayed in a manner that supports the decision strategies invoked to achieve the goal states of the process being controlled. Hence, in designing interfaces to support real-time dispatch management decisions, it is suggested that it would be necessary to first discover the goal states and the decision strategies invoked during the process, and then portray the required information in a manner that supports such a user group's decision making goals and strategies.
The purpose of this paper is to report on the experiences gleaned from the use of a cognitive task analysis technique called Critical Decision Method as an elicitation technique for determining information portrayal requirements. This paper firstly describes how the technique was used in a study to identify the goal states and decision strategies invoked during the dispatch of ambulances at the Sydney Ambulance Co-ordination Centre. The paper then describes how the interview data was analysed within and between cases in order to reveal the goal states of the ambulance dispatchers. A brief description of the resulting goal states follows, although a more detailed description of the goals states and their resulting display concepts has been reported elsewhere (Wong et al., 1996b). Finally, the paper concludes with a set of observations and lessons learnt from the use of the Critical Decision Method for developing display design concepts in dynamic intentional environments.
