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Finding qualitative research: Searching specific databases

Using search filters

A hedge or filter is a standardised search strategy that is designed to be used in conjunction with a subject search to retrieve valid studies from the (primary) medical or health sciences literature.  

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Filters work in one of two ways by:

  • identifying particular publication types or study designs most likely to answer a question
  • isolating subject or free-text terms most likely to be associated with high quality studies                                                                                                                    

Methodological search filters focus on the methods of qualitative research rather than the content. They are often combined with the search terms. They can be a:

  • sensitive filter - search maximises the retrieval with the risk of more irrelevant articles being retrieved
  • specific filter - narrows the search but there is a possibility of missing relevant articles
  • best balance filter - gives a search that provides a good balance between sensitivity and specificity

See specific database filters for PubMed, Medline, CINAHL and PsycINFO in the adjacent box.

Searching using filters - PubMed, Medline, CINAHL and PsycINFO


In Medline do your search for your topic and then do either of the following:

1. Click on additional limits and then under Clinical Queries, choose Qualitative (best balance of sensitivity and specificity).

2. Experiment with related the following Medical Subject Headings (MeSH) Qualitative Research, Interview as Topic, Focus Groups, Nursing Methodology Research, Personal Narratives as Topic or Observational Study as Topic. 

Combine your topic search with either the Clinical Queries limit or the qualitative MeSH headings.


In CINAHL do a search for your topic and then:

  1. Tick Suggest Subject Terms.
  2. Enter the term qualitative studies and click Search
  3. Click on the link Qualitative Studies to see the types of qualitative research:
  • Action Research
  • Ethnographic Research
  • Ethnological Research
  • Ethnonursing Research
  • Grounded Theory
  • Naturalistic Inquiry
  • Phenomenological Research

Experiment with related CINAHL subject headings  such as Focus Groups

Refine/Limit the results to Clinical Queries and select your option from the dropdown menu (Qualitative - Best Balance retrieves the best balance between Sensitivity and Specificity

Refine/Limit the results to Publication Types that are qualitative by definition, for example, Anecdote or Interview

To find articles that may have been missed by CINAHL subject headings, use the relevant keywords that you may discover in a good article that you have retrieved.

Qualitative research search filter example
Copy and paste the following filter into PsycINFO (Ovid) and combine your subject terms with this search filter:
((("semi-structured" or semistructured or unstructured or informal or "in-depth" or indepth or "face-to-face" or structured or guide or guides) adj3 (interview* or discussion* or questionnaire*)).ti,ab,id. or (focus group* or qualitative or ethnograph* or fieldwork or "field work" or "key informant")).ti,ab,id. or exp qualitative research/ or exp interviews/ or exp group discussion/ or qualitative not "Literature Review".md.
Courtesy of the Library at University of Texas Health Science Center at Houston

Qualitative research search filter example

Copy and paste the following filter into PubMed and combine your subject terms with this search filter:

(((“semi-structured”[TIAB] OR semistructured[TIAB] OR unstructured[TIAB] OR informal[TIAB] OR “in-depth”[TIAB] OR indepth[TIAB] OR “face-to-face”[TIAB] OR structured[TIAB] OR guide[TIAB] OR guides[TIAB]) AND (interview*[TIAB] OR discussion*[TIAB] OR questionnaire*[TIAB])) OR (“focus group”[TIAB] OR “focus groups”[TIAB] OR qualitative[TIAB] OR ethnograph*[TIAB] OR fieldwork[TIAB] OR “field work”[TIAB] OR “key informant”[TIAB])) OR “interviews as topic”[Mesh] OR “focus groups”[Mesh] OR narration[Mesh] OR qualitative research[Mesh] OR "personal narratives as topic"[Mesh]

PubMed Health Services Research (HSR) Queries

  • From the PubMed home page Select Topic - Specific Queries under PubMed Tools
  • Click on Health Services Research (HSR) Queries. This page provides a filter for specialized PubMed searches on healthcare quality and costs.
  • Enter your search topic and select Qualitative Research under Category
  • Choose either the broad or narrow scope (for more details click on this filter table)