Research Guides: Systematic Reviews & Evidence Synthesis: Choosing for dissertations or theses

Which review type works best for you?

Reviews for Dissertations / Theses / Capstones

Have you been inspired (or told) to do a systematic review? Let's make sure a systematic review is right for you!

Literature reviews fall along a spectrum in terms of being systematic, with systematic reviews requiring every aspect of the methodology to be systematic, and literature (or narrative) reviews, which do not require every aspect to be systematic. No matter which search methodology best matches your project's needs, you can still take a systematic approach to strengthen your review. The chart below is a useful guide to differences between methodologies at each end of the spectrum: a systematic review and a narrative review.

Searches for systematic review versus literature review
Systematic review	Literature (or narrative) review
Search strategies must be replicable Document database names & platforms (e.g., Medline/Ovid, CINAHL/EBSCO), search dates, all search terms & limits used in the methods section of a publication or in an appendix. Librarians or other informationists who create the search strategy often write the methods section.	Search strategies do not need to be replicable Normally not published in the methods section. Are less detailed when published.
Follow specific search methodologies that ensure comprehensive results Search strategies are highly sensitive to retrieve relevant articles. Many databases are searched. Other sources, such as ClinicalTrials.gov & hand searching, are used.	Searches vary in how comprehensive they are Search strategies may not be as comprehensive in: search terms used the number of resources that were searched.
Require a significant time commitment Because of the methodology of systematic reviews, they can take 18-24 months to complete, even with a team involved.	Take much less time The time frame depends on the topic, what you are trying to achieve with the search, & thus how comprehensive the search needs to be, but it can be significantly shorter.
Typically retrieve high number of results Searches produce large numbers of search results because of the sensitivity of an SR search strategy. Citations are excluded after manual review	Retrieve lower number of results These searches retrieve fewer results than SR search strategies because they are more specific than sensitive. A manual review may not be necessary.
Require a team Generally, two or more individuals independently review each article separately to determine whether it meets inclusion criteria. Conflicts are solved by a third party.	Can be completed by individuals Results do not need to be reviewed for inclusion or exclusion by multiple individuals.
Protocol-driven Answers a specific clinical question. Has specific inclusion & exclusion criteria. Uses methods for assessing bias.	Does not use a protocol

Reproduced from University of Michigan Library’s guide Evidence Syntheses (Scoping, systematic, & other types of reviews) under CC-BY 4.0 license

What is a Systematic Review?

The specific guidelines for how to conduct a systematic review differ by field of study, but the core process is generally the same.

Scope and develop a focused research question (pre-planning phase)
Write a protocol for the conduct of the project and register it publicly
Develop and conduct a comprehensive and systematic search of the literature
Screen all results of that search using predetermined inclusion/exclusion criteria
Extract the relevant data from the research/articles that passed through the screening process
Appraise the quality of the research/articles you selected
Analyze and synthesize the data as appropriate to the data type (quantitative/qualitative/mixed)
Write and publish the review

Process steps for performing a systematic review

What is the Goal & Why Does it Matter?

The goal of a systematic review is to provide a clear, evidence based recommendation for practice or policy in a very specific situation based on the existing evidence and its quality.

Systematic reviews have a narrow focus but search comprehensively across a large body of literature to answer that narrow question.

If this is not an appropriate goal for your thesis/capstone/dissertation, then there are other review types that may be better suited.

Overall, identify your research question first, and then determine if a systematic review or other evidence synthesis method is appropriate for that question.

Do You Have a Research Team?

A research team is an essential component for systematic reviews and almost all other evidence synthesis projects. This can be a challenge for graduate students! Figure out if you have a team to work with before getting too far into these projects.

If you do not have a research team, you can:

use a different term to refer to your project (see tab 'Shorter timelines possible?')
conduct a pilot project version of a systematic review or scoping review
conduct a critically appraised topic review or state-of-the-art narrative literature review
conduct a high-quality, comprehensive traditional literature review.

Scope and Viability

At the start of this process, it is almost impossible to be certain how many included studies you will ultimately have in your project. Make sure you have the time and capacity to deal with a high volume of results and a plan B if there is nothing.

You can help yourself mitigate some of these risks:

conduct extensive exploratory searching to locate "seed" articles that you think will make it though your inclusion criteria
make certain there are no existing published or planned systematic reviews on your research question
test your inclusion/exclusion criteria against a sample set of search results to make certain they function well for identifying an appropriate results set for your research goals
write a thorough and clear protocol outlining exactly what you will do, why you are doing it, how it will be done, who will be involved in what capacity, and which software you will use during this process

Reproduced from Colorado State University Library's guide Systematic Reviews & Evidence Synthesis under CC-BY-NC-SA 4.0 license

What if I Don't Have a Team/Time, But I Still Want to Do a Systematic Review?

For any publication purposes (article, poster, conference presentation, etc.), many projects that do not have research teams or do not have resources to follow the full methodological guidelines are best described as:

Structured Literature Review
Systematized (Scoping/Integrative) Review
Comprehensive Review
Systematized Search and Review
Pilot Systematic/Scoping/Integrative Review

These title adjustments acknowledge that the authors recognize the proper methods, goals, and guidelines for conduct of systematic reviews and other types of evidence synthesis projects. These methods were used wherever possible, but the resources were not available to meet full methodological guidelines.

Alternatively, there are a few evidence synthesis project types that can be produced on short timelines and/or without a full research team. Check out the Other Review Types page.

Reproduced from Colorado State University Library's guide Systematic Reviews & Evidence Synthesis under CC-BY-NC-SA 4.0 license