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Systematic Reviews

What is a Systematic Review?

A systematic review is a formal research study. It follows a clear, predefined structure to find, assess, and analyze studies that have all tried to answer a similar question. The results of a systematic review can provide a reliable picture of what we know - and what remains uncertain. It usually takes many months to do a systematic review.

Systematic review methods aim to minimize bias in reviewing research. Bias can result from a weakness or flaw in the way a review was designed, the way it was done, or the way it was analyzed.

Are you a student needing to conduct a systematic review for your course? A Librarian can consult with you on the process.  

Source: What is a Systematic Review?. Pubmed Health[Internet]. Bethesda (MD): National Library of Medicine (US)

Is a Systematic Review for You?

Systematic Reviews, for publication, can take upwards of 12-18 months.

If you do not have the time to commit, consider other reviews options. 

Where do you start?

Check to see if a systematic review already exists on your topic.  If one does, think about how yours will build upon this and other past work. You might need to choose a different topic. Search the Cochrane Database of Systematic Reviews, PubMed and other databases such as CINAHL, to find reviews.  In PubMed search for existing systematic reviews by apply the Article Type - Systematic Review filter to your search, or use this link to begin a search for systematic reviews and simply add your topic terms:[Publication%20Type]

Creating a protocol or a research plan is an important first step for your review. It gives direction to your project by defining your research question. Protocols are used to describe your topic, the rationale, inclusion/exclusion criteria and planned methods for the review. Preparing your research plan before the start of the review will help keep your project on track. 

If you are planning to publish your review, registering your protocol is an indication of your plans to other researchers. Major review organizations, like the Cochrane Collaboration, require a protocol be developed and registered before a review is begun. 

The following are resources that make creating a protocol or proposal easier:

  • PRISMA-P checklist: provides a list of items that should be considered when planning your review and that should be included in any protocol that you develop.
  • Methodological Expectations for Cochrane Intervention Reviews:  lists the methodological standards that Cochrane reviews must adhere to. Even if you're not doing a Cochrane review, there is helpful guidance in the section on "Developing the Protocol for the Review."
  • University of Kentucky's DMPToolUK Libraries has developed a protocol development tool that is freely available. You will find a template with detailed guidance and examples. Please do not use DMPTool to register your protocol, you will need to download the PDF and register it.

It is recommended that you register your protocol before conducting your review.  Registering your protocol in a publicly accessible database will improve transparency as well as alerting other researchers of your intentions so efforts are not duplicated. It is a best practice to search for publicly registered reviews on your topic before starting the review process.  Registering your protocol helps to avoid unintended duplication of reviews and increases transparency.

Where to Register Your Protocol

Where to Publish a Protocol or finished Review

Systematic Reviews: Create a Protocol University of Kentucky Libraries

Systematic Review Service

Librarians with expert searching skills are available to assist researchers, review teams and graduate students in developing  effective search strategies for comprehensive reviews such as systematic reviewsscoping reviewsintegrative reviews, etc.  


For those students, a librarian can help you in:

  • Identifying relevant databases
  • Identifying and combining relevant search terms
  • Exporting search results into a citation/review manager
  • Identifying sources of grey literature
  • Identifying other means of finding relevant studies

Depending on the research question, number of databases and available librarian time, it takes around 1-2 weeks for the librarian to consult and/or develop all search strategies. 


For those who plan to publish their review, here's how a librarian can help: 

  • Literature Searching (not including hand searching the literature).
  • Refining the research questions and planning the search strategy. 
  • Pinpointing appropriate databases and grey literature.
  • Providing all search strategies and number of results for each database, as well as date searched. 
  • Exporting results into a citation manager like Endnote or Zotero
  • Removing duplicates from the EndNote or Zotero library, and providing a final count of documents.
  • Writing the search methodology section, if requested.
  • This service is fee based:
    • $25 per hour, with the first hour being free
    • We accept MoCode or Check

Depending on the research question, number of databases and available librarian time, it takes around 4-6 weeks for the librarian to consult and/or develop all search strategies. 

Before you Meet With A Librarian

To get a better sense of your project, we suggest making an appointment with a librarian. 

Before your consultation, we suggest you do the following prior to the consultation:

  • Educate yourself about the type of review you will be undertaking
  • Familiarize yourself with the processes involved for that type of review
  • Develop a protocol/proposal for your prospective review
    • If you have already developed a protocol/proposal, provide this to the librarian you will be meeting with.
    • If you haven't already developed a protocol/proposal, take a look at how to create one. 
  • Find 2-5 articles that fit your research question.
  • If you do not already have some basic familiarity with search principles, consider viewing Finding Health Literature: Keys to Searching PubMed, CINAHL & Scopus