Formal specification of temporal constraints in clinical practice guidelines

In the last years, both clinical evidence and expert consensus have been codified in the form of clinical practice guidelines in order to promote an actual empowerment in the overall quality of care. Even if different solutions have been realized to specify temporal constraints in computerized guidelines, none of them proposes a formal language as the basis of guideline formalism in order to easily and directly support the temporal perspective. In such a direction, this paper proposes a formal approach, which has been seamlessly embedded into a standards-based verifiable guideline model, named GLM-CDS (GuideLine Model for Clinical Decision Support). Such an approach hybridizes the theoretic semantics of ontology and rule languages to specify a variety of temporal constraints according to some time patterns, i.e., task duration, periodicity, deadline, scheduling and time lags. These constraints are then encoded in the form of rules verifiable at run-time during the guideline enactment, in order to support the detection of violations or errors occurred with respect to the temporal perspective. As an example of application of the proposed approach, some temporal constraints have been integrated in GLM-CDS and verified by using a reasoning engine, according to the time patterns identified.