Searching for studies

The Cochrane ENT Information Specialist offers Cochrane ENT review authors a full searching service. As part of this role they develop and maintain the Cochrane ENT Trials Register. The Register contains reports of randomised controlled clinical trials and quasi-randomised controlled trials (RCTs and qRCTs) related to the scope of the Group. The register was established in 1998 and contains 27,000 reports of trials in ENT/head and neck cancer (as of May 2018). The majority of these are submitted for inclusion in the Cochrane Central Register of Controlled Trials (CENTRAL). Follow this link for further details.

Search strategies for the identification of studies for inclusion in Cochrane Reviews

The Cochrane ENT Information Specialist constructs subject search strategies for bibliographic databases based on the concepts represented in the protocol for the review. Index terms and free-text terms (i.e. terms appearing in the title/abstract of anticipated search results) should be included in subject search strategies, and the inclusion of synonyms, abbreviations and spelling variations will help to ensure that all relevant literature is captured. These will be combined, when applicable (based on the type of studies to be included in the review), with a RCT search filter to identify reports of trials. The search filters used by Cochrane ENT (available here) are appropriate for this task. Cochrane ENT will use the highly sensitive search strategy designed by Cochrane for identifying randomised controlled trials and controlled clinical trials (as described in the Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0, Box 6.4.b). The Cochrane ENT Information Specialist will consider the use of the sensitivity and precision-maximising filter in specific circumstances, where appropriate.

The strategy is adapted and run across multiple electronic databases. A minimum electronic search will include searches of:

  • the Cochrane ENT Trials Register;
  • the Cochrane Central Register of Controlled Trials (CENTRAL);
  • Ovid Medline or Pubmed;
  • Ovid Embase;
  • Web of Science, Web of Knowledge;

In addition, the Information Specialist will consider adding searches of the following (determined by the topic of the review):

In addition to the above formal database searches, Cochrane ENT authors are expected to review the reference lists of relevant trials and systematic reviews. The Information Specialist will routinely run non-systematic searches of Google Scholar to retrieve grey literature and other sources of potential trials. Additional searches of Regulatory Databases for Clinical Study Reports may be considered, based on specific criteria, as well as forward citation searching of included studies via the Web of Science Citation Index.