Using Part-Whole Statecharts for the safe modeling of clinical guidelines

Behavioral aspects of medical guidelines can be modeled and formalized in a straightforward way by flow diagrams. However, safety plays a critical role in both modeling and formalization given the intermingled involvement of human actors and medical devices which have to interact and coordinate according to precise rules and strict timelines. Although state based formalisms can be shown to be very apt in depicting complex situations in both an intuitive and formal manner, they do not provide modular constructs for defeating complexity and require model checking in order to be verified against safety requirements. The paper proposes to adopt a modular and hierarchical state based formalism for the sake of representing behavioral aspects in medical guidelines. Such a formalism can be shown to provide a natural arrangement of different fault management strategies at the different decomposition levels.