MEDLINE contains records from 5600 journals (39 languages) in the of biomedical field, from 1946 onwards (Access for KCE | Free access through PubMed).
EMBASE: Records from 7600 journals (70 countries, 2000 not covered by Medline) in biomedical field, from 1974 onwards (Access for KCE).
CENTRAL - The Cochrane Controlled Trials Register, part of the Cochrane Library: Records of randomised controlled trials and controlled clinical trials in healthcare identified through the work of the Cochrane Collaboration including large numbers of records from MEDLINE and EMBASE as well as much material not covered by these databases (Dickersin, 2002). (Access for KCE through CDLH | Free access to abstracts)
Special queries exist for Medline or Embase to limit the identified records to articles identified as Systematic reviews. See appendix.
Databases for HTA reports
The INAHTA HTA database is a bibliographical database of published HTA reports; it also lists ongoing HTA projects. Members of INAHTA are regularly invited to update their information on the HTA database, informaiton from the main HTA producers is also collected by the database maintainer. Access is free, records of the HTA database are also searchable via the Cochrane Library.
Physiotherapy: PEDro (contains records of RCTs, systematic reviews and evidence-based clinical practice guidelines in physiotherapy, from 1929 onwards; most trials in the database have been rated for quality to quickly discriminate between trials that are likely to be valid and interpretable and those that are not; free access)