Querying Clinical Workflows by Temporal Similarity ⋆ Carlo Combi 1 , Matteo Gozzi 1 , Jose M. Juarez 2 , Roque Marin 2 , and Barbara Oliboni 1 1 Department of Computer Science – University of Verona – Italy {combi|gozzi|oliboni}@sci.univr.it 2 Dept. of Information and Communication Engineering – Universidad de Murcia – Spain {jmjuarez|roque}@dif.um.es Abstract. The degree of fulfillment of clinical guidelines is considered a key factor when evaluating the quality of a clinical service. Guidelines can be seen as processes describing the sequence of activities to be done. Consequently, work- flow formalisms seem to be a valid approach to model the flow of actions in the guideline and their temporal aspects. The application of a guideline to a spe- cific patient (guideline instance) can be modeled by means of a workflow case. The best (worst) application of a guideline, represented as a reference workflow case, can be used to evaluate the quality of the service, by comparing the optimal case with specific patient instances. On the other hand, the correct application of a guideline to a patient involves the fulfillment of the guideline temporal con- straints. Thus, the evaluation of the temporal similarity degree between different workflow cases is a key aspect in evaluating health care quality. In this work, we represent a portion of the stroke guideline using a temporal workflow schema and we propose a method to evaluate the temporal similarity between workflow cases. Our proposal, based on temporal constraint networks, consists of a linear combi- nation of functions to differentiate intra-task and inter-task temporal distances. 1 Introduction In the past years, clinical guidelines have received an increasing attention in the med- ical community, but also in the academic context for research issues related to clinical guidelines modeling [9]. Clinical guidelines describe, in natural language, the recom- mended behaviour of a medical team, the activities to apply to the patient, and their fulfillment with respect to the time and to the the state of patient health, for defining the best way to manage patients. The number of clinical guidelines, covering almost all major branches of medicine, is growing up, together with their updates delivered after regular reviews and new scientific discoveries. In this work we consider the Italian guideline for stroke prevention and management (SPREAD) [8]. This guideline aims to provide knowledge and recommendations about primary and secondary prevention of stroke in clinical practice. The diffusion of guidelines in an electronic form is spreading out, and allows the physicians to compare and evaluate clinical guidelines coming from different countries but focusing on the same clinical activities. Despite the diffusion of electronic versions ⋆ This work was partially supported by the Spanish MEC under the FPU national plan (grant ref. AP2003-4476) and the national projects TIC2003-09400-C04 / TIN2006-15460-C04-01. R. Bellazzi, A. Abu-Hanna, and J. Hunter (Eds.): AIME 2007, LNAI 4594, pp. 469–478, 2007. c  Springer-Verlag Berlin Heidelberg 2007