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Systematic literature studies, Health & Sport

Library subject page. The University Library, Agder University


Break up your topic into concepts (search elements) and find search terms for each concept. Start with the most important element (concept), choose more if needed

A broad sensitive search includes words from text words and subject heading words (index words)

Text word, or free-text words -  are words from the author, included in the title or abstract of the article or the author keywords

Subject heading words are words from the database controlled vocabulary used to index articles., also called index terms or controlled vocabulary term or descriptors. Used in database records to make searching easier. By standardizing the words or phrase used to represent concepts, you don't need to figure out all the ways different authors could refer to the same concept (APA)


Figure: from a MEDLINE record (in EBSCOhost). The Subject headings in MEDLINE is called MeSH (Medical Subject Headings)

The Contributed indexing is words from the Author keywords. The same reference in PubMed


Subject headings

Database Subject headings Look up

MeSH (Medical subject headings)

Publication types

MesH Browser
Norwegian translation
MEDLINE from PubMed, EBSCOhost or Ovid: Map term to subject headings, or use the Search tool or Expand term finder. 


CINAHL Subject headings

Publication type



Publication types

EMTREE in Ovid: Map term to subject headings, or use the Search tool or Expand term finder. 

APA PsycInfo

 APA Thesaurus of Psychological Index Terms

Also notice these controlled vocabulary fields

Publication type

Age group

Classification codes

APA Thesurus of Psychological index terms, in Ovid: Map term to subject headings, or use the Search tool or Expand term finder. 

Look also into the information about the database, fields to see information about codes related to publication types, age group, methodology etc.

Example Publication types field in APA PsycInfo

See also information from APA


  1. Newer articles may not be fully indexed  with subject headings in the databases, result: Even if you find a perfect Subject heading match to your concept, you have to include text word  (free text words) as well. Tip: Look into the entry terms (Synonyms) to see different words you can apply in the free-text search. Example from MeSH Browser Neoplasm In Ovid, Look into the information about the subject headings, and the field: Used for
  2. Some articles (records in the database) is the wrong index
  3. Some concepts do not have a corresponding subject heading

So: we also need to search with the text word for a broad sensitive search


Read more

Aromataris, E., & Riitano, D. (2014). Constructing a search strategy and searching for evidence. A guide to the literature search for a systematic review. Amerian Journal of Nursing, 114(5), 49-56.

Bramer, W. M., de Jonge, G. B., Rethlefsen, M. L., Mast, F., & Kleijnen, J. (2018). A systematic approach to searching: an efficient and complete method to develop literature searches. Journal of the Medical Library Association: JMLA, 106(4), 531–541.


Ovid Search tool:  Map term to subject heading

Search tool (Map to term heading, Permuterm index etc)


Expand term finder

start with a relevant article if you know, or do a simple search with words you already think suits the concepts

From relevant articles, examine the words used in title, abstract and subject headings.Look also into similar articles, often a function in the databases, and cited by. Also check reference list

do a new search with the new words

and so on

ALSO go to the Subject heading browser, like MeSH to see if subject headings fits the concept, and if narrowing or broader headings should be included.

Tip do a simple search in the databases:

in basic PubMed search, go to Advanced search, see the history search detail if PubMed has been able to map to a correct MeSH heading word/phrase. Also, sort the result on Best matches and take a closer look at the articles if you find relevant.

You can do the same in CINAHL or MEDLINE through EBSCOhost. Look to the left Subject headings used often among the articles in the search result. On the top of the sceen you can go to the headings and take a closer look at the Subject headings.

In Ovid Basic search run a simple search without any boolean or truncated words, check the most relevant articles for words in title/abstract and subject heading fields

Save all the relevant words for the final search in a document. Also, document decisions as you go on

Read more

Aromataris, E., & Riitano, D. (2014). Constructing a search strategy and searching for evidence. A guide to the literature search for a systematic review. Amerian Journal of Nursing, 114(5), 49-56. 

MeSH - Medical subject headings, help:

MeSH Browser

MeSH within PubmMed, also see below

Swedish Mesh 

Norsk MeSH  

MeSH on demand

 PubMed PubReMiner

Yale Mesh analyzer


Notice that PubMed automatic will include MeSH in a basic search without using field codes and trunctions. Go to search history detail to see how PubMed has executed the search. Also from relevant articles from the search look into the information about the articles, sort the hist on best match

Using Medical Subject headings in Ovid MEDLINE (video from OUTulsaLibrary). 
Note that finding Subject headings in EMTREE and APA PsycInfo is similar to MEDLINE. Use only one database when checking for subject headings! Go to Ovid from UiA access


Qualitative studies

Search with a block for qualitative studies/designs:Possible often used words:

qualitative OR phenomenolog*  OR interview* OR experienc* OR themes OR thematic OR Ethnographic* OR Ethnological* OR "grounded theor*" OR ethnonursing*  OR  audiorecording* OR hermeneutic*  OR "content analys*" OR "focus group*" OR Audiorecording*

Read more:

  • Wilczynski, N. L., Marks, S., & Brian Haynes, R. (2007). Search Strategies for Identifying Qualitative Studies in CINAHL. Qualitative Health Research, 17(5), 705–710.
  • Ann McKibbon, K., Wilczynski, N. L., & Brian Haynes, R. (2006). Developing Optimal Search Strategies for Retrieving Qualitative Studies in PsycINFO. Evaluation & the Health Professions, 29(4), 440–454.
  • PDQ Evidence-Based Principles and Practice (2nd Edition), Kap. 9 /edited by Ann McKibbon, and Nancy Wilczynski
  • ...

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Text mining tools

Glanville, J (2018). Text Mining Opportunities:White paper. Ottawa : CADTH. Link

Stansfield, C., O'Mara-Eves, A. & Thomas, J. (2017). Text mining for search term development in systematic reviewing: A discussion of some methods and challenges. Res Synth Methods, 8(3), 355-365.





PubMed PubReminer 

Systematic Review Accelerator


Text Analyzer


Voyant Tools 



Alternatives apps, tools for bibliotemetrics, also used for finding search words :

R package litsearchr:

Grames, EM, AN Stillman, MW Tingley, and CS Elphick (2019). An automated approach to identifying search terms for systematic reviews using keyword co-occurrence networks. Methods in Ecology and Evolution 10: 1645-1654. 

Shiny APP in development: not need to download R studio


R package Bibliometrix 


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