The review protocol sets out the methods to be used in the review and provides an explicit plan for your work. Decisions about the review question, inclusion criteria, search strategy, study selection, data extraction, quality assessment, data synthesis and plans for dissemination should be addressed. If modiﬁcations to the protocol are required, these should be clearly documented and justiﬁed. Modiﬁcations may arise from a clearer understanding of the review question, and should not be made because of an awareness of the results of individual studies.
Protocols help the systematic team stay on track and answering the original question, not something else. It also establishes a time-frame so it assists the team moving forward along the timeline.
The protocol should include:
Search question or objective
Inclusion/exclusion criteria (scope including types of studies, participants, interventions)
Databases to be searched
Proposed search strategy
Methodology for data extraction and analysis
Declaration of interests
Protocols can be used as in-house documentation or can be registered to increase visibility of what you're undertaking. This may link you with other researchers with the same interests or alert others that your systematic review is in process and avoid duplication. You should also check to be sure someone else has not submitted a protocol similar to the one you're thinking of doing.
Consider registering your protocol. PROSPERO, from the Centre for Reviews and Dissemination at the University of York, is an international database of registered reviews in health and social care. Key features from registered reviews and recorded and maintained as a permanent record. Registration helps to promote transparency in the review process and also reduces the potential for duplication.
The Campbell Collaboration is an international research network that produces systematic reviews of the effects of social interventions in Crime & Justice, Education, International Development, and Social Welfare.
PROSPERO is an international database of prospectively registered systematic reviews in health and social care. PROSPERO aims to provide a comprehensive listing of systematic reviews registered at inception to help avoid unplanned duplication and enable comparison of reported review methods with what was planned in the protocol.