Electronic literature databases are important tools when searching for medical information but the selection and coverage of databases affects the search results. In the case of health science, the choice of databases is not always easy, as some of the material may be scattered in databases focusing on different fields. Often PubMed is the only database used in medical research. The aim of this study is to examine the coverage of literature databases and to identify the best databases or combinations of databases in different topics in psychiatry.

We performed database searches on four different topics. The topics were ADHD prevalence, schizotypal personality, brain MR imaging studies in schizophrenia and recovery in schizophrenia. A systematic retrieval of studies was performed in three databases (PubMed, Web of Science and PsycINFO). We studied also if publication years or language of the articles affect database coverage.

PubMed was most comprehensive database in ADHD (85% coverage of total results) and in MRI studies (71%), whereas PsycINFO was most effective in recovery (62%) and in schizotypal personality (72%). The most comprehensive combination of two databases found 78-91% of the articles in the different topics.

When choosing databases for information search the extent of coverage should be taken into account, as there is no database that covers all information needs. The used literature databases should be selected bases on the topic. In psychiatry, especially in topics related to psychology also PsycINFO should be considered. In all, use of several databases is recommended.