Background:

It is good practice in systematic reviews (SRs) to publish the search strategy used for each database, as recommended by the Cochrane Handbook for Systematic Reviews of Interventions. These can be used to inform future related reviews and update searches. However, it is currently not considered necessary to publish information about which databases held the relevant records and whether these were found by the search. Tracking and publishing this information as an additional search summary will aid future reviewers in choosing and using resources more effectively and will improve the efficiency of update searches.

Objectives:

To develop a search summary table that can easily be used at the end of all SRs to discover:
1. which databases the included references came from;
2. which other databases searched found the reference but it was excluded as a duplicate;
3. which other databases searched contained the reference but the search did not pick it up.

Methods:

The search summary was designed and developed by the authors over six systematic reviews including one Cochrane Systematic Review. These were then used to establish whether a future search on the same topic (or an updated search for the same review) could be carried out more efficiently with targeted database searching.

Results:

The results for each systematic review show, via a summary table, in which databases the included studies were found. An overall picture of the six summaries has also been produced to discover whether any pattern has emerged from the individual results.

Conclusions:

The search summary will inform future systematic reviews including updates to SRs or the update searches as part of the SR. This will provide evidence to the review team about which databases to search, particularly if there are time constraints. It will also be another step in sharing and refining search data.