[Systematic literature search to make HTA (health technology assessment) reports]

Health technology assessment should describe the existing evidence of a medical technology independently and complete. Because of the enormous amount of scientific publications worldwide, systematic literature investigation is essential to identify all publications of relevance. Systematic investigation implies especially hierarchical and standardized modes. The most important resources to identify publications that already contain a synthesis of information are specialized databases covering secondary literature. A standardized search strategy consists of several steps: conception (incl. specification of methodological and content-related inclusion and exclusion criteria), selection of databases, preparation of a query, and carrying out the search, finally. The identified publications--this could be several hundreds up to some thousands--have to be assessed by applying the a priori defined criteria and a decision has to be made whether to include or exclude documents for the health technology assessment report.