When embarking on your literature search, you need search words that will cover the topics and perspectives you are interested in. Once you have found your search words, you should assemble them into search strings, so you are able to do precise and well-defined searches for literature that specifically covers your problem field or the topic you are interested in researching. Your search terms (and search strings) will evolve from being more simple and covering more general concepts initially, to becoming more precise, specific and complex.
We recommend that you follow these steps:
1.1 Start by brainstorming on your search words
1.2 Sort your search words into blocks or aspects
1.3 Use search techniques such as Boolean operators to combine your search words.
It is important that you consider your search words carefully before the start of your literature search. In this way, you ensure that you cover all the ways your topic could be mentioned and treated in the literature.
Start by looking at your problem formulation and problem field and brainstorm about 10-15 search words that could be relevant. While doing this, consider whether there are similar concepts for the search terms you already have (including synonyms, inflections, abbreviations, and language variations). Also consider whether there are search words that can give you more specific or more general searches, and whether it makes sense to include search words that reflect your methodology or approach.
In the illustration below, you can see an example of a brainstorm on search words, where the problem field deals with stress among midwives in hospitals.
| Problem field | Stress among midwives in hospitals |
| Search words | Stess, midwives, hospital |
| Synonyms | burnout, anxiety, midwife, public health care |
| Methodology/Type of study | case study, interview |
Once you have found relevant search words, it can be a good idea to divide the words into aspects and organize them into blocks. This way, it becomes easier for you to get an overview of the field you are searching in, and you can, for example, quickly make your search broader or more specific by adding or removing a word or a block/aspect.
In the illustration below, the different search words are organized according to synonyms, similar words, and concepts that deal with the same aspects.
| Aspect 1 | Aspect 2 | Aspect 3 | Aspect 4 |
| Midwi* | Stress | Hospital* | "Case study" |
| Burnout | "public health care" | Interview* | |
| Anxiety |
Once you have sorted your search words into thematic blocks or aspects, you can perform a block search using the Boolean operators AND and OR. AND is added between each block and OR between each search word in the individual blocks. Place parentheses around each block where you use OR between search terms.
An example of a block search could look like this:
midwi* AND (stress OR burnout OR anxiety) AND (hospital* OR “public health care”)
Your search string does not need to include all search words and synonyms at the same time. Use the block search to get an overview of the different aspects of your problem field and assemble the search words as needed.
Databases vary in content and structure, in their treatment of keywords, and in how precisely you can or should search. These differences can affect the search technique you use. Therefore, it is important to adapt the search strategy to each individual database.
Use the databases’ help functions and FAQs to get an overview of functions and search techniques.
You can improve and refine your search by using:
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BOOLEAN OPERATORS
Boolean operators can be used in soeg.kb.dk as well as in all databases. Use them to combine your search terms and thereby form search strings.
AND narrows down your search and makes it more precise. You will only find results where all your search words are included. Example: stress* AND midwife
OR expands your search and gives you the opportunity to include synonyms, or similar words and concepts, in your search string. Here, one or both/more of your search words can appear in the results.
Example: stress* OR overload*
NOT can be useful if, as in the example below, you want to get literature that deals with stress among midwives, but you are not interested in mentioning anything about private hospitals. However, you should be careful when using this operator, as you risk excluding important literature. Note how the operators are combined using parentheses. We write more about this below.
Example: (stress* AND midwife) NOT "private hospital"
You can easily make a search where you combine the Boolean operators. Here, it is just important that you tell the database with parentheses which words are synonyms (OR) and which are not (AND).
Example: (stress* OR overload*) AND midwife
PHRASE SEARCH
By putting quotation marks around a phrase or a concept consisting of two or more words, you tell the database or search engine to search for the words so they stand next to each other and not individually.
Examples:
“work life balance”
“work environment”
“private hospital”
“public health care”
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By placing an asterisk (*) at the end of a word, you tell the database or search engine to search for the stem of the word and all possible endings.
Example:
Stress*
Stressed
Stressful
Stressor
Stress...
Once you have found your search terms, you need to assemble them into search strings using different search techniques. See how to build search strings using Boolean operators and other search techniques in the examples above.
The search strings are what you are going to insert into the databases or the library catalogue. It will then search for books, articles, etc., where the words included in your search string are also included in the text of the books/articles.
Especially in the databases, do you have the opportunity to limit whether the words should be included in the title, abstract, the entire text, or the assigned subject words. This makes your search more or less specific.
Most of the time, different information needs require different search strings. Also note that your search strings will probably need to be adjusted once you have started your searches and, for example, find new search terms.
Examples of search strings:
midwi* AND (stress OR burnout)
midwi* AND (stress OR burnout) AND “public health care”
You can download a work paper for your literature search. It can help you work strategically and structured with your literature search. The working paper is organized like the six step-model of literature search, as we describe in this libguide
Generative AI like Copilot and ChatGPT can help with parts of your literature search process, but should never be used as a solution for the entire process from steps 1-6.
Generative AI is helpful with generating search words as a supplement to step 1.1.
Read our libguide on AI Practice before you start using AI.