Made available in DSpace on 2016-08-29T15:33:17Z (GMT). No. of bitstreams: 1 tese_5084_.pdf: 1868850 bytes, checksum: 22f46d96f48ef171f653cbcd277c6088 (MD5) Previous issue date: 2012-08-22 / Epidemiology is a field of study in Medicine which seeks to understand the factors that determine the frequency and distribution of diseases in humans. This field allows one to understand the phenomena of health and disease of a particular population by generating this populations epidemiological profile. The knowledge provided in this profile allows a shift in the focus from treating to preventing diseases, which is an important aim of the current Brazilian health care program. This dissertation proposes a system to study the epidemiological profile in a basic health care unit. This system applies an ontology as basis for modeling and querying the epidemiological information. An ontology is a conceptual model which captures an specific view of a domain of discourse. This model may be used to structure the systems information, which later can be queried also with basis on this same ontology. A preliminary validation of this systems prototype has shown that it is able to successfully generate the health care units epidemiological profile, providing new knowledge about the patients and treatments involved in this unit. Such prototype may now be applied in this real setting to guide the actions of health care professionals in dealing with hypertension and other health conditions. In order to develop the system, a goal-oriented methodology based on Tropos is applied. This methodology guides software development since an early stage of organizational modeling until the systems implementation by using current standards for ontology implementation. Many of the available ontology engineering methodologies presuppose the existence of a set of questions which provide the objective and scope of the ontology under development. However, these so-called competency questions are not always clear from start. The highlight of the proposed methodology is applying goal analysis to assist the ontology engineer to reason about and model competency questions. Following this view, such competency questions are comparable to system requirements, elicited and modeled during the requirements engineering stage of a software development process. Both the developed system and the proposed methodology are contributions of this work. However, while the former has proven to be useful in practice, further steps must be carried out in order to properly validate the latter, by applying it to other cases.