A protocol is a plan that specifies the objectives and methods for your review before it begins. It also provides direction and clarity for the review team members.
“The preparation of a protocol is an essential component of the systematic review process; it ensures that a systematic review is carefully planned and that what is planned is explicitly documented before the review starts, thus promoting consistent conduct by the review team, accountability, research integrity, and transparency of the eventual completed review.” PRISMA-Protocols Statement Paper
A protocol should describe the rationale for the review and outline the methods that will be used to locate, select, critically appraise, analyse and synthesise relevant studies and data. It increases transparency and minimises bias by clearly defining the research question, stating the review objectives, and outlining the full process for completing the review, including a systematic search of at least one database.
By predefining the scope and methods, protocols help prevent unintentional shifts in focus or selective reporting, ultimately strengthening the integrity of the review. Your completed protocol can be registered and/or published to let other researchers know a review is underway and help avoid duplication and research waste.
PRISMA-Protocols (PRISMA-P) is a useful tool for developing a review protocol. Although it was designed for systematic reviews, relevant elements can be applied, where appropriate, to other types of reviews. The Checklist contains recommended items to be addressed in a protocol.
There are several guidelines available to help with writing protocols, including:
Protocol registration sites may also provide guidance.
The purpose of a protocol is to clearly and transparently describe how the review will be conducted for both reviewers and readers. A protocol usually includes the following components:
Administrative details – provide information about the review, such as the title, registration details, authors, stakeholders, funding, etc.
Rationale – provide justification for why the review is being carried out and how it will contribute to what is already known.
Review question/s and objectives – include an explicit statement of the question/s the review will address, with reference to participants, intervention, comparators and outcomes where appropriate. Include any frameworks used to develop the research question/s.
Eligibility criteria - specify the study characteristics (such as PICO, study design, setting, and time frame) and report characteristics (such as years covered, language, and publication status) to be used as eligibility criteria for the review. The criteria should reflect the PICO or other framework elements and be agreed upon by all reviewers before screening starts.
Information sources – specify the databases that will be systematically searched to identify studies for inclusion in the review. Also, list any additional sources to be searched, such as trial registries, grey literature, and relevant websites, and state the planned date range for coverage.
Search strategy – include a draft or sample search strategy for at least one database, including planned limits. The aim is to present a strategy that reasonably represents the final version and can be clearly followed and replicated by others.
Managing, selecting and appraising studies – describe how records and data will be managed throughout the review, and explain the process that will be used to screen and select studies through each phase. If included, describe how critical appraisal will be conducted.
Data extraction - describe the planned method of determining what data will be extracted from selected studies and how it will be extracted.
Assessing risk of bias – if included, describe anticipated methods for assessing risk of bias of individual studies, and specify whether this will be done at the outcome level, study level, or both.
Data synthesis and reporting – explain how data will be synthesised, presented and reported.
If you are planning a systematic review, scoping review, or similar type of review, you should consider registering a review protocol early in the process. Registering a protocol improves transparency and helps reduce bias in the conduct of the review. It also allows other researchers to discover reviews in progress, which reduces the likelihood of duplicated effort.
Open Science Framework (OSF) - A free, open-source tool that facilitates open collaboration in research. Protocols are assigned a DOI. See Registrations & Preregistrations home page and What is Preregistration?
Figshare - A free, open access academic repository. Protocols are assigned a DOI.
Zenodo - A free, general purpose, open repository. Protocols are assigned a DOI.
Protocols.io - An open repository for protocols. A basic account is free. Protocols are assigned a DOI.
PROSPERO - An international registry of systematic, rapid and umbrella review protocols with health-related outcomes. Scoping review protocols are not accepted. Registration is free and each protocol is assigned a unique registration number. See how to register a review in PROSPERO.
Joanna Briggs Institute (JBI) Systematic reviews - the JBI Manual for Evidence Synthesis states that JBI systematic review authors must register their review protocol with PROSPERO prior to the conduct and publication of the review. JBI SUMARI (System for the Unified Management of the Assessment and Review of Information) is a software package designed to assist in the conduct of JBI systematic reviews. Access to SUMARI is available through JBI Best Practice database (Ovid). See the SUMARI knowledge base for information on setting up a systematic review project and protocol. Scoping reviews - JBI recommends that scoping review protocols be registered with Open Science Framework or Figshare. See the JBI Scoping Review protocol template. If you are working on a review for a JBI-affiliated entity, you can also register the title and brief details on the JBI Systematic Review Register.
Cochrane Library - Includes protocols of Cochrane systematic reviews. To undertake a Cochrane review, you must first submit a proposal, and if accepted, you will be invited to submit a draft protocol. See How to write a Cochrane protocol. The protocol must be published before you begin the full review, and each protocol is assigned a DOI.
Campbell Collaboration - An international social science research network that produces high-quality, open and policy-relevant evidence syntheses, plain language summaries and policy briefs. To publish a review in Campbell Systematic Reviews, you must first submit a title registration form and the protocol for approval. See Campbell forms, templates and guidelines.
International Database of Education Systematic Reviews (IDESR) - A database of published systematic reviews in education, as well as a clearinghouse for registering protocols of ongoing and planned systematic reviews.
PROCEED - A global database of prospectively registered evidence reviews (systematic reviews and others) relevant to the environmental sector (e.g., science, management and policy). Protocols are assigned a DOI.
Research Registry - A database register of all types of research studies. Protocols can be registered in the Registry of Systematic Reviews/Meta-Analyses for a fee.
INPLASY - The International Platform of Registered Systematic Review and Meta-analysis Protocols is a platform where systematic and scoping review protocols can be registered for a fee. Protocols are assigned a DOI.
Registered protocol examples
Briggs, A., Slater, H., Siegfried, N., Waller, R., Romero, L., O’Connell, N., Klem, N.-R., & Kwesi Ampiah, P. (2025). Systematic review and appraisal of clinical practice guidelines for the care of people experiencing chronic primary pain with interpretation aligned to an established chronic pain care priority framework (CRD420251000482). PROSPERO. https://www.crd.york.ac.uk/PROSPERO/view/CRD420251000482
Staniland, L., Martin, L. T., Myers, B., & Rudaizky, D. (2025, February 24). Exploring mental health support and intervention for parents of neurodivergent children: A scoping review. OSF. https://doi.org/10.17605/OSF.IO/DGJR6
Registering your protocol does not prevent you from also publishing it in a journal. Registries are used to publicly record protocols, whereas journal publications undergo peer review and become part of the scholarly record. Some journals that publish protocols (APC fees may apply):
NOTE: Journals may state that they publish protocols; however, this may refer to randomised controlled trials (RCTs) or other study types rather than review protocols. Check the journal submission guidelines for confirmation. Some journals require protocol registration prior to starting the review. Check the author instructions to confirm whether protocol registration details should be included in manuscripts for both review protocols and the final review report or article, e.g. JBI Evidence Synthesis. Some journals require payment of an Article Publishing Charge (APC) to publish. Check the journal details or Curtin’s open access publishing agreements.
Published protocol examples
Campbell, A. C., Pearce, L. A., Willoughby, M., Borschmann, R., Young, J., Bruun, A., Sundbery, J., & Kinner, S. (2023). Adverse childhood experiences, morbidity, mortality and resilience in socially excluded populations: Protocol for a systematic review and meta-analysis. BMJ Open, 13, Article e074314. https://doi.org/10.1136/bmjopen-2023-074314
Freeman, N., Bradfield, Z., Cheney, K., & Warland, J. (2023). Midwives’ and registered nurses’ role and scope of practice in acute early pregnancy care services in Australia: A scoping review protocol. JBI Evidence Synthesis, 21(4), 826-832. https://doi.org/10.11124/JBIES-22-00198
Haile, T. G., Wallace, H., Manuel, J., & Estai, M. (2026). Engagement in research capability-building: Impact on healthcare workforce attraction and retention in rural and remote Australia – A scoping review protocol. PLOS ONE, 21(1), Article e0340289. https://doi.org/10.1371/journal.pone.0340289
Wakgari, N., Tessema, G. A., Watson, S. J., Bekele, D., & Bradfield, Z. (2025). Women’s experiences and outcomes of abortion care in sub-Saharan countries: A mixed methods systematic review protocol. PLOS ONE, 20(1), Article e0318488. https://doi.org/10.1371/journal.pone.0318488
Brackett, A., & Batten, J. (2020). Ensuring the rigor in systematic reviews: Part 2, preparation is key: The question and the protocol. Heart & Lung, 49(6), 965-966. https://doi.org/https://doi.org/10.1016/j.hrtlng.2020.07.001
Butler, A., Hall, H., & Copnell, B. (2016). A guide to writing a qualitative systematic review protocol to enhance evidence-based practice in nursing and health care. Worldviews on Evidence-Based Nursing, 13(3), 241-249. https://doi.org/https://doi.org/10.1111/wvn.12134
Lely, J., Morris, H. C., Sasson, N., Camarillo, N. D., Livinski, A. A., Butera, G., & Wickstrom, J. (2023, May 31). How to write a scoping review protocol: Guidance and template. OSF. https://doi.org/10.17605/OSF.IO/YM65X
Peters, M. D. J., Godfrey, C., McInerney, P., Khalil, H., Larsen, P., Marnie, C., Pollock, D., Tricco, A. C., & Munn, Z. (2022). Best practice guidance and reporting items for the development of scoping review protocols. JBI Evidence Synthesis, 20(4), 953-968. https://doi.org/10.11124/JBIES-21-00242
Pieper, D., & Rombey, T. (2022). Where to prospectively register a systematic review. Systematic Reviews 11, Article 8. https://doi.org/10.1186/s13643-021-01877-1
The PLoS Medicine Editors. (2011). Best practice in systematic reviews: The importance of protocols and registration. PLoS Med 8(2), Article e1001009. https://doi.org/10.1371/journal.pmed.1001009