4.1 Designing a scope or generic search

Many CISs design, run, check and evaluate scope search strategies (sometimes called generic search strategies). If you are working as a CIS in an established Group, you may not have to design scope strategies, but you will need to check them periodically to ensure that the search terms used (especially the MeSH terms) are current and relevant.

Scope search strategies are very broad and are designed to capture all trial reports within the Group’s scope. If you need to design, evaluate or update your Group’s generic searches, a good place to start is the Scope and Topic List of your Group. Each Group’s Topic List is structured and it can be used to identify search terms. Developing or updating scope search strategies usually requires assistance from other members of the Group (Editors, Co-ordinating Editor, Managing Editor, subject experts and your colleagues) to help identify all the relevant search terms.

Designing a scope or topic search strategy usually involves combining sets of terms to search for:

  • the health condition of interest to your Group , i.e. the population
  • the types of study design that you wish to retrieve e.g. RCT, CCT, CBA or ITS (often you would use a ‘filter’ for study design as described below)

These strategies are generally combinations of database thesaurus terms (e.g. MeSH or Emtree terms), and free text words (e.g. terms found in the title or abstract of a record) and a study design ‘filter’.

Filters are search strategies designed to retrieve reports of a particular study design (e.g. RCT or CCT). The Cochrane Highly Sensitive Search Strategy (HSSS) for identifying randomized trials in MEDLINE has been objectively derived and tested and can be added to the topic component of your search strategy to retrieve RCTs and CCTs in your field.

4.1.1 References

See an example of a MEDLINE scope search using healthcare conditions and a study design filter (Appendix 4).

See an example of a CENTRAL scope search using healthcare conditions (Appendix 5).

For full details on search filters, see the Cochrane Handbook, Section 6.4.11: "Search filters".

For information about how to identify randomised trials in MEDLINE, see the Cochrane Handbook, Section "Cochrane Highly Sensitive Search Strategies for identifying randomised trials in MEDLINE".

For suggestions for terms to use to create an RCT filter in Embase, see the Cochrane Handbook, Section "What is in the Cochrane Central Register of Controlled Trials (CENTRAL) from EMBASE?" These suggestions have not yet been validated.

For another controlled trials filter that has been created and validated for the Embase project, see the Cochrane Library help page on CENTRAL

"Identifying Embase RCTs and CCTs for inclusion in CENTRAL", subheading "Ongoing search and retrieval of records", section "Set 2: Records retrieved by the new search".

The InterTASC Information Specialists' Sub-Group Search Filter Resource is a collaborative venture to identify, assess and test search filters designed to retrieve research by study design or focus. The resource aims to provide easy access to published and unpublished search filters.