Systematic Reviews

What is a systematic review protocol?

• It provides a map of the review for every stage of the process
• Documenting the plan or protocol prior to completing the review reduces the bias and improves the validity
• A registered protocol establishes provenance of the research project for the specific question

Why should a team register a protocol: 

• A protocol is considered best practice by the Cochrane Handbook and the PRISMA Guidelines for Systematic Reviews
• Reduces bias by establishing your criteria a priori
• Much of the information within the protocol will assist with the article format and writing

Source: Fundamentals of Systematic Review Protocols

Inclusion and Exclusion Criteria: 

• Developed to define the parameters of the research question
• Determine the limits of the evidence synthesis
• Exclusion criteria must be justified
• All criteria are presented and defined within the methods section with the search strategy

Examples of Inclusion and Exclusion Criteria:

• Date: generally the search for evidence in a systematic review is run for the entirety of the databases existence. However, it the review is being completed to update a previous study, the run date will begin when the last study ended. 
• Exposure of Interest: (as designated in the research question) If the review is specifically interested in the outcome related to a specific exposure, only studies evaluating that exposure will be included within the review. 
• Geographic location: Global, within the United States, urban or rural, colleges or universities, etc. 
• Language: Commonly a review will limit the studies included to those written in English due to translation issues. 
• Participants: (as designated in the research question) 
• Reported outcomes: Objective outcomes specifically related to the research question
• Setting: Clinical, hospital, lab, school, community, etc. 
• Study design
• Type of publication: Determines if the review will include only peer reviewed evidence, grey literature, dissertations, conference abstracts and papers, etc.