Background: Identifying studies that are relevant to the public health field can be challenging. The public health field is broad, and interventions can be complex involving many varied settings, communities and populations. Also there is a lack of uniform terminology to describe and organise the field. Controlled trials are often not suitable for evaluating public health interventions and therefore controlled before and after and interrupted time series designs are frequently utilised. The combination of these elements can require the use of more complex search methods such as searching a broad number of databases that are relevant to the particular public health topic.

Objectives: This current project follows on from a well received poster that was presented at the 18th Cochrane Colloquium (Mann M et al. Searching for success for a public health intervention review). Mann et al. investigated the need to search multiple databases to identify evidence for their review of collaboration between local health and government agencies, concluding that it was an important component of the review process. We will expand the investigation to 12 Cochrane reviews relevant to public health to further analyse if searching multiple databases is essential in conducting a public health review.

Methods: From the 12 reviews we will identify which databases searched by the authors retrieved the included studies.

Results: We will provide data on which resource retrieved each included study, if a study is unique to a particular database and the proportion that were identified from either Medline, Embase or the Cochrane Library.

Conclusions: The results will be useful for trial search coordinators in providing guidance to authors and to authors themselves in planning their searches, and will include guidance on a 'core set’ of databases to search for public health topics.