To realize the potential of the Internet as a source of valuable healthcare information, for the general public, patients or practitioners, it is imperative to establish a validation system based on standards of quality. The WRAPIN project (Worldwide online Reliable Advice to Patients and Individuals) from the European Community has this ambitious goal. WRAPIN is a federating system for medical information with an editorial policy of intelligently sharing quality and professional information. The WRAPIN project has two main axes: the efficient and intelligent search of information and the assertion of the trustworthiness of content.

This article presents the scientific challenges involved in extracting the knowledge from text-based information in order to better manage the knowledge and the rest of the retrieval process. Our innovative approach is to efficiently extract MeSH terms from the analyzed documents exploiting UMLS knowledge sources'. A benefit has been measured when comparing extraction results. Even if the evaluation is made with a limited corpus, this research work proposes heuristics that can be validated to the whole biomedical domain, and possibly enhanced by the adjunction of other methods.