The Cochrane Handbook emphasises the importance of the development of a protocol:
“Publication of a protocol for a review prior to knowledge of the available studies reduces the impact of review authors’ biases, promotes transparency of methods and processes, reduces the potential for duplication, allows peer review of the planned methods before they have been completed, and offers an opportunity for the review team to plan resources and logistics for undertaking the review itself”.
PLoS Medicine editors published the following article on the importance of protocols in systematic reviews:
Best Practice in Systematic Reviews: The Importance of Protocols and Registration (2011) PLoS Med 8(2): e1001009. doi:10.1371/journal.pmed.1001009
Watch a short video on guidelines and protocols (1:15).
The development of a review protocol not only helps in establishing the researcher’s approach to a high level review, but can also act as a 'live' document that the researcher can draw on and use during the lifetime of the review.
A high level review is an important piece of research therefore a protocol should clearly define the journey the review will take. Not all of these steps apply to the Integrative review. Please see the Integrative Overview to identify the steps required for your protocol.
The protocol include:
There are several standards and guidelines available to assist in developing the protocol for the systematic review.
The inclusion and exclusion criteria are critical components in a high level review, as the search needs to be replicable. Researchers need to ensure that they are clear on the exact results they want to locate from their search.
The criteria help in eliminating any bias during the selection and extraction phases.
Some examples of what you may include in criteria might be:
It is best practice to register your protocol, as you do not want anyone else to do exactly same review you are doing or start undertaking a review to later find out someone is already undertaking the same review.
A good place to register a health review is PROSPERO . (Systematic Reviews only)
PROSPERO is an international, free to search database of prospectively registered systematic reviews in health and social care. Before registering your review check to see if your protocol is eligible for registration. Once you register, your review will:
For more information, see the Guidance notes for registering a systematic review protocol with Prospero (2016) prepared by the University of York and the National Institute for Health Research (NHS).
You can publish your protocol in the following journals and databases:
For further information about publishing your review please visit the Scholarly Publishing Guide.
'Provide registration information for the review, including register name and registration number, or state that the review was not registered.'
'Indicate where the review protocol can be accessed, or state that a protocol was not prepared.'
'Describe and explain any amendments to information provided at registration or in the protocol.'
- PRISMA 2020 Explanation and Elaboration, p. 28
Cochrane Handbook, part 2, chapter 3: Defining the criteria for including studies and how they will be grouped for the synthesis
This chapter provides recommendations for the Protocol, including how to define criteria for included studies and how they will be grouped for synthesis.
The Cochrane Handbook, part 1, chapter 3: Reporting of protocols of new Cochrane reviews
This chapter details the necessary components of protocols for SRs conducted for the Cochrane Collaboration.