One of the challenges in medical information retrieval is the terminology gap between the documents (commonly written by medical professional, using medical jargons), and the queries (commonly composed by non professional, using layman terms). In this thesis, we investigate the effect of query expansion, using domain-specific knowledge resource, to deal with this challenge. We use the Unified Medical Language System (UMLS), a repository of biomedical vocabularies, and utilize two of its resources: the Metathesaurus and the Semantic Network. We use the query set and document set provided by CLEF eHealth organizer. The query sets, provided for the medical information retrieval shared task, represent two different use cases of medical information retrieval. We experiment with query expansion using synonymous terms and non-synonymous concepts, blind relevance feedback, field weighting, and linear interpolation of different systems. Powered by TCPDF (www.tcpdf.org)

(in English) The thesis examines the use of medical thesauri and classifications in portals containing medical information for laymen. The thesis first describes the selected thesauri, classifications and individual portals. A survey was carried out exploring users' reasons for researching medical information. Subsequently, selected subjects were observed researching information on previously selected portals. The observation was complemented with semi- structured interviews with the subjects. The observed results were used to discern the key manifestations of the connection between portals and medical thesauri. The individual portals were further evaluated and their features most important to users were identified.

This thesis deals with automatic acquiring thesauri from Wikipedia. It describes Wikipedia as a suitable data set for thesauri acquiring and also methods for computing semantic similarity of terms are described. The thesis also contains a description of concepts and implementation of the system for automatic thesauri acquiring. Finally, the implemented system is evaluated by the standard metrics, such as precision or recall.

The objective of the dissertation thesis has been the information-lexical analysis of Czech medical reports and the usability of international classification systems in the Czech healthcare environment. The analysis of medical reports has been based on the attributes of the Minimal Data Model for Cardiology (MDMC). Narrative medical reports and structured medical reports from the ADAMEK software application have been used. For the thesis SNOMED CT and ICD-10 classification systems have been used. There has been compared how well attributes of MDMC are recorded in narrative and structured medical reports. The language analysis of the Czech narrative medical reports has been made. A new application for measuring diversity in medical reports written in any language is proposed. The application is based on the general concepts of diversities derived from f-diversity, relative f- diversity, self f-diversity and marginal f-diversity. The thesis has come to the conclusion that using a free text in medical reports is not consistent and not standardized. The standardized terminology would bring benefits to physicians, patients, administrators, software developers and payers and it would help healthcare providers as it could provide complete and easily accessible information that belongs to the process of...

The objective of the dissertation thesis has been the information-lexical analysis of Czech medical reports and the usability of international classification systems in the Czech healthcare environment. The analysis of medical reports has been based on the attributes of the Minimal Data Model for Cardiology (MDMC). Narrative medical reports and structured medical reports from the ADAMEK software application have been used. For the thesis SNOMED CT and ICD-10 classification systems have been used. There has been compared how well attributes of MDMC are recorded in narrative and structured medical reports. The language analysis of the Czech narrative medical reports has been made. A new application for measuring diversity in medical reports written in any language is proposed. The application is based on the general concepts of diversities derived from f-diversity, relative f- diversity, self f-diversity and marginal f-diversity. The thesis has come to the conclusion that using a free text in medical reports is not consistent and not standardized. The standardized terminology would bring benefits to physicians, patients, administrators, software developers and payers and it would help healthcare providers as it could provide complete and easily accessible information that belongs to the process of...

The master's thesis deals with Information Retrieval. It summarizes the knowledge in the field of Information Retrieval theory. Furthermore, the work gives an overview of models used in Information Retrieval, the data and the actual issues and their possible solutions. The practical part of the master's thesis is focused on the implementation of methods of information retrieval in textual data. The last part is dedicated to experiments validating the implementation and its possible improvements.