Inclusion criteria are the criteria that resources must have in order to be considered, by you, to be relevant to your search needs.
For example, if your search inquiry specifies a patient population of a certain age, then the inclusion criteria will be that age group.
Exclusion criteria are the criteria that resources should not have in order to be considered, by you, to be relevant to your search needs.
For example, if your search inquiry specifies a date range, then the exclusion criteria will be any dates outside of that range.
The methods you use to organize and construct your search, as well as how you choose to report your search strategy and results.
When you are creating your inclusion and exclusion criteria, be sure to keep your research question in mind.
Walk yourself through the PICO(TS) process again:
Remember to be open-minded as you move through the literature. Sometimes developing inclusion and exclusion criteria follows the "I don't know what I don't know" rule, so you may learn more about how researchers have discussed your topic, which may begin to inform your interests and criteria for inclusion.
As you identify criteria for inclusion and exclusion, make note of them. I would recommend doing so within the literature matrix (described to the right) as a column. This will assist you in tracing which articles were included for which reasons, and which articles were excluded for which reasons. This allows for greater transparency, and for an overall higher quality of literature review.
Defined by Garrard as: "a structured abstract of all the source documents from your literature review" (2017). A spreadsheet is often recommended and employed in the literature matrix, where "each column has a topic--such as author/title/journal, year, purpose, or type of study design--and each row consists of a journal article" (Garrard, 2017). The key to the literature matrix is that it is versatile as a tool of organization, so there is no "right" or "wrong" way to utilize one. The benefit to using a literature matrix is in the paper trail that it creates for you the writer--you will not have to try to remember each article individually; instead, after a review of the articles that seem relevant to you, you write down brief notes in the matrix, and then move on to the next article. This allows you to create a document that can be used for quick reference and recall when you need it.
|Column 1 example:
Author, title, journal
|Column 2 example:
|Column 3 example:
|Column 4 example:
Type of study design
Journal article 1
|1995||Drug treatment for epilepsy||Experimental study|
Journal article 2
|1997||Drug treatment||Case-control study for depression|
If 4 columns does not feel like a sufficient amount of information for you to gather on each article, you may add as many columns as you wish. For scientific literature, Garrard suggests including: hypothesis, independent variables, dependent variable, methodological design, and sample (2017).
However, you need to decide what makes the most sense for the type of literature you are collecting.
Garrard, J. (2017). Health Sciences Literature Review Made Easy: The Matrix Method (5th ed.). Retrieved from https://librarycatalog.ecu.edu/catalog/4760351.
PRISMA stands for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The PRISMA Statement was developed to facilitate the transparent reporting of systematic review and meta-analysis processes. This empowers readers of systematic reviews to ascertain for themselves the quality of the review without having to rely on the authors' assurance alone. The PRISMA Statement includes a 27-item checklist, as well as a flow diagram (described below). The flow diagram is often found in the Methods section of a well-designed systematic review.
The PRISMA Checklist is not in itself a quality assessment tool; rather, it is a list of items that facilitates transparent reporting for reviewers.
An example of the Checklist is below:
To access the complete PRISMA Checklist for free, visit the following link:
PRISMA Statement Checklist: http://prisma-statement.org/PRISMAStatement/Checklist.aspx
PRISMA Flow Diagram
Utilizing the PRISMA Flow Diagram allows authors to transparently describe to their readers the decision-making process as inclusion and exclusion criteria were applied to individual articles. In the systematic review and meta-analysis, transparency is a requirement. In other forms of writing, it is considered a sign of a high quality review.
Throughout your graduate work, you may be asked to describe your literature review process to your reader, as well. One of the easiest, and certainly visually appealing, methods of reporting your process is the PRISMA Flow Diagram. This diagram helps your reader to visualize how you may have gone from retrieving thousands of articles to selecting fewer than 100 in your list of references.
To generate your own PRISMA diagram, there are a few free resources: