“Gathering research, getting rid of rubbish and summarizing the best of what remains captures the essence of the science of systematic review. Nevertheless, although the need to synthesize research evidence has been recognized for well over two centuries, it was not until the 20th century that researchers began to develop explicit methods for this form of research.” (Grant & Booth, 2009, p. 92)
As a PhD candidate, you are expected to place your work in the context of current research. Reviewing scholarly literature, i.e. analysing and making a synthesis of various results, points of view or approaches, is critical to every work of research, but how this is done depends on the discipline and the requirements of the individual research project.
On this page will you learn about
It is recommended to conduct the literature review in the beginning of the research project, even though you might come back to it during the writing process. The final literature review (or the review parts) of your dissertation will be the result of a number of steps:
However, depending on the individual project and discipline, it may be necessary to repeat these steps during your PhD. The research question and the literature search and review are mutually interrelated:
It is recommended to gain an overview of your field of research from the start of your work. Regardless of whether you are writing a literature review as a separate part of your dissertation or whether you are reviewing literature throughout your writing, relating your work to previous research is a crucial requirement in all scholarly literature.
Reviewing literature helps you to
The ‘literature review’ is […] your opportunity to engage in a written dialogue with researchers in your area while at the same time showing that you have engaged with, understood and responded to the relevant body of knowledge underpinning your research. (Ridley, 2012, p. 3)
Your PhD cannot be done in isolation from previous research. Your inclusion of existing literature will show how well you know your field of research, as well as demonstrating that your research will fill gaps in current knowledge. Read more about how to relate to previous research.
While you are searching, reading and evaluating, your search results will, on the one hand, focus your search and limit the amount of text you will have to read, while on the other hand, they will constantly lead you to new references and new aspects of the research. Evaluation is first and foremost a question of discipline-based judgements. Your evaluation can include
In order to define a framework for your search and to delimit the focus of your literature review, it can be useful to draft an overview of the inclusion and exclusion criteria for your literature review.
Inclusion and exclusion criteria: an example from a literature review in teacher education (Evans, Fraser & Cotter, 2014, p. 535)
The following criteria were used for the inclusion or exclusion of studies in this systematic review:
Methods of reviewing literature can vary considerably, depending on the discipline, topic and individual research project. The research process in medicine and the sciences is usually based on a predefined research question, a systematic search prior to the actual research and standardized forms of theses. In the humanities and social sciences, however, searching, reviewing literature and writing are most often intertwined parts of the research process. But stand-alone literature reviews also vary widely. A literature review may be
In order to learn more about typical methods and standards of reviewing literature in your field of research, it is recommended to study some dissertations and find examples of best practice.
Find out more about different types of literature reviews.
Arksey, H., & O’Malley, L. (2005). Scoping studies: towards a methodological framework. International Journal of Social Research Methodology, 8(1), 19-32. https://doi.org/10.1080/1364557032000119616
Boote, D., & Beile, P. (2005). Scholars before researchers: On the centrality of the dissertation literature review in research preparation. Educational Researcher, 34(6), 3-15. https://doi.org/10.3102/2F0013189X034006003
Booth, A., Sutton, A., & Papaioannou, D. (2016). Systematic approaches to a successful literature review (2nd ed.). Los Angeles, CA: Sage.
Evans, C. B. R., Fraser, M. W., & Cotter, K. L. (2014). The effectiveness of school-based bullying prevention programs: A systematic review. Aggression and Violent Behavior, 19(5), 532-544. https://doi.org/10.1016/j.avb.2014.07.004.
Foster, M., & Jewell, S. (2017). Assembling the pieces of a systematic review : a guide for librarians. Lanham, Maryland: Rowman & Littlefield.
Grant, M. J., & Booth, A. (2009). A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information and Libraries Journal, 26(2), 91-108. https://doi.org/10.1111/j.1471-1842.2009.00848.x
Greenhalgh, T., Thorne, S., & Malterud, K. (2018). Time to challenge the spurious hierarchy of systematic over narrative reviews? European Journal of Clinical Investigation, 48(6). https://doi.org/10.1111/eci.12931
Krumsvik, R. J., Øfstegaard, M. & Jones, L. Ø. (2016). Retningslinjer og vurderingskriterier for artikkelbasert ph.d. Uniped, 39(01), 78-93. https://doi.org/10.18261/issn.1893-8981-2016-01-07
Moher, D., Stewart, L., & Shekelle, P. (2015). All in the family: systematic reviews, rapid reviews, scoping reviews, realist reviews, and more. Systematic Reviews, 4(1), 183. https://doi.org/10.1186/s13643-015-0163-7
Ridley, D. (2012). The literature review. A step-by-step guide for students (2nd ed.). London: Sage.