QOC-E: A mediating representation to support the development of shared rationale and integration of Human Factors advice

Abstract

Designing and manufacturing medical devices is a complex and specialist effort. Throughout the process,
there is an opportunity to consult across those involved in various aspects of development (for example
Human Factors (HF), Human Computer Interaction (HCI), Design and Manufacture). Developers report
difficulties in this area, speaking of isolated team members and organizational / cultural barriers. We
illustrate the use of a mediating representation (Questions, Options, Criteria and Evidence - QOC-E) that
promotes shared reasoning and can be used to capture design rationale. Application is demonstrated using
an illustrative example involving the specification of a number entry mechanism. The benefits of the QOC
scheme include making tacit reasoning explicit, articulation of trade-offs, traceability, allowing
compartmentalization of the design and avoidance of fixation in any one particular area. Downsides include
the fact that the representation may require prohibitive amounts of effort to maintain or fail to scale to large
or complex systems. These issues are discussed and directions for further investigation outlined.