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Library Guide to Capstone Literature Reviews: Find a Research Gap

Find a research gap: tips to get started

Finding a research gap is not an easy process and there is no one linear path. These tips and suggestions are just examples of possible ways to begin. 

In Ph.D. dissertations, students identify a gap in research. In other programs, students identify a gap in practice. The literature review for a gap in practice will show the context of the problem and the current state of the research. 

Research gap definition

A research gap exists when:

  • a question or problem has not been answered by existing studies/research in the field 
  • a concept or new idea has not been studied at all
  • all the existing literature on a topic is outdated 
  • a specific population/location/age group etc has not been studied 

A research gap should be:

  • justified
  • grounded in the literature
  • original
  • amenable to scientific study

Identify a research gap

To find a gap you must become very familiar with a particular field of study. This will involve a lot of research and reading, because a gap is defined by what does (and does not) surround it.


  • Search the research literature and dissertations (search all university dissertations, not just Walden!).
  • Understand your topic! Review background information in books and encyclopedias
  • Look for literature reviews, systematic reviews, and meta-analyses.
  • Take notes on concepts, themes, and subject terms
  • Look closely at each article's limitations, conclusions, and recommendations for future research. 
  • Organize, analyze, and repeat! 

Start with broad searches

Use the Library Search (formerly Thoreau) to do a broad search with just one concept at a time. Broad searches give you an idea of the academic conversation surrounding your topic.

  • Try the terms you know (keywords) first.
  • Look at the Subject Terms (controlled language) to brainstorm terms. 
  • Subject terms help you understand what terms are most used, and what other terms to try.
  • No matter what your topic is, not every researcher will be using the same terms. Keep an eye open for additional ways to describe your topic.

Keep a list of terms

This list will be a record of what terms are: 

  • related to or represent your topic
  • synonyms or antonyms
  • more or less commonly used
  • keywords (natural language) or subject terms (controlled language)

Term I started with:

culturally aware 

Subject terms I discovered:

cultural awareness (SU) 

cultural sensitivity (SU) 

cultural competence (SU) 


Search with different combinations of terms

Since a research gap is defined by the absence of research on a topic, you will search for articles on everything that relates to your topic. 

You will:

  1. List out all the themes related to your gap.
  2. Search different combinations of the themes as you discover them (include search by theme video at bottom) 

For example, suppose your research gap is on the work-life balance of tenured and tenure-track women in engineering professions. In that case, you might try searching different combinations of concepts, such as: 

  • women and STEM 
  • STEM or science or technology or engineering or mathematics
  • female engineering professors 
  • tenure-track women in STEM
  • work-life balance and women in STEM
  • work-life balance and women professors
  • work-life balance and tenure 

Topic adapted from one of the award winning Walden dissertations. 

Break your topic into themes and try combining the terms from different themes in different ways. For example: 

Theme 1 and Theme 4

Theme 2 and Theme 1

Theme 3 and Theme 4


Example Topic Themes and Related Terms
Theme 1
and related terms
Theme 2 
and related terms
Theme 3
and related terms
Theme 4
and related terms
Theme 5 and related terms
women STEM tenure track work life balance professor 
female science or technology or engineer or mathematics tenured work-life-balance faculty


Video: Search by Themes (YouTube)

Track where more research is needed

Most research articles will identify where more research is needed. To identify research trends, use the literature review matrix to track where further research is needed. 

  1. Download or create your own Literature Review Matrix (examples in links below).
  2. Do some general database searches on broad topics.
  3. Find an article that looks interesting.
  4. When you read the article, pay attention to the conclusions and limitations sections.
  5. Use the Literature Review Matrix to track where  'more research is needed' or 'further research needed'.
    NOTE:  you might need to add a column to the template.
  6. As you fill in the matrix you should see trends where more research is needed.

There is no consistent section in research articles where the authors identify where more research is needed. Pay attention to these sections: 

  • limitations
  • conclusions
  • recommendations for future research