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Structured Study Protocol Template

Trials is experimenting with a new way of structuring study protocols for randomised trials. The simple innovation is to include all 51 SPIRIT headings and item identifiers within the protocol itself. Readers will then benefit from the ability to search by item identifier, which are contained within curly brackets.
This is not mandatory and we will continue to consider protocols submitted in other formats, with the inclusion of a SPIRIT checklist.

For more information, read this Editorial from co-Editor-in-Chief, Shaun Treweek: Protocols—more structure, less ‘Wuthering Heights’

Trials guidance: the numbers in curly brackets (e.g. {5a}) are SPIRIT item identifiers.  Please do not remove them, or any heading that contains them.  The item identifiers are slightly out of sequence to make the document flow more easily but it is important that they remain in the document to allow electronic searches by SPIRIT item number.

Download link (Microsoft Word Document): Trials_structured_Study_Protocol_Template.docx


[SPIRIT guidance: Descriptive title identifying the study design, population, interventions, and, if applicable, trial acronym.]

Names protocol contributors

[Trials guidance: Names of protocol contributors.]


[Trials guidance: The Abstract should not exceed 350 words. Please minimize the use of abbreviations and do not cite references in the abstract. The abstract must include the following separate sections:

  • Background: the context and purpose of the study
  • Methods: how the study will be performed
  • Discussion: a brief summary and potential implications
  • Trial registration: If your article reports the results of a health care intervention on human participants, it must be registered in an appropriate registry and the registration number and date of registration should be in stated in this section. If it was not registered prospectively (before enrollment of the first participant), you should include the words 'retrospectively registered'. See our editorial policies for more information on trial registration.]



[Trials guidance: Three to ten keywords representing the main content of the article.]

Administrative information

[Trials guidance: please include the following text in your submitted protocol just above the Administrative information table:]

Note: the numbers in curly brackets in this protocol refer to SPIRIT checklist item numbers. The order of the items has been modified to group similar items (see

Title {1}

[SPIRIT guidance: Descriptive title identifying the study design, population, interventions, and, if applicable, trial acronym.]

Trial registration {2a and 2b}.

[SPIRIT guidance: Trial identifier and registry name. If not yet registered, name of intended registry.

Item 2b is met if the register used for registration collects all items from the World Health Organization Trial Registration Data Set.]

Protocol version {3}

[SPIRIT guidance: Date and version identifier.]

Funding {4}

[SPIRIT guidance: Sources and types of financial, material, and other support.]

Author details {5a}

[SPIRIT guidance: Affiliations of protocol contributors.]

Name and contact information for the trial sponsor {5b}

[SPIRIT guidance: Name and contact information for the trial sponsor.]

Role of sponsor {5c}

[SPIRIT guidance: Role of study sponsor and funders, if any, in study design; collection, management, analysis, and interpretation of data; writing of the report; and the decision to submit the report for publication, including whether they will have ultimate authority over any of these activities.]


Background and rationale {6a}

[SPIRIT guidance: Description of research question and justification for undertaking the trial, including summary of relevant studies (published and unpublished) examining benefits and harms for each intervention.]

Objectives {7}

[SPIRIT guidance: Specific objectives or hypotheses.]

Trial design {8}

[SPIRIT guidance: Description of trial design including type of trial (eg, parallel group, crossover, factorial, single group), allocation ratio, and framework (eg, superiority, equivalence, noninferiority, exploratory).]

Methods: Participants, interventions and outcomes

Study setting {9}

[SPIRIT guidance: Description of study settings (eg, community clinic, academic hospital) and list of countries where data will be collected. Reference to where list of study sites can be obtained.]

Eligibility criteria {10}

[SPIRIT guidance: Inclusion and exclusion criteria for participants. If applicable, eligibility criteria for study centres and individuals who will perform the interventions (eg, surgeons, psychotherapists).]

Who will take informed consent? {26a}

[SPIRIT guidance: Who will obtain informed consent or assent from potential trial participants or authorised surrogates, and how (see Item 32).]

Additional consent provisions for collection and use of participant data and biological specimens {26b}

[SPIRIT guidance: Additional consent provisions for collection and use of participant data and biological specimens in ancillary studies, if applicable.]


Explanation for the choice of comparators {6b}

[SPIRIT guidance: Explanation for choice of comparators.]

Intervention description {11a}

[SPIRIT guidance: Interventions for each group with sufficient detail to allow replication, including how and when they will be administered.]

Criteria for discontinuing or modifying allocated interventions {11b}

[SPIRIT guidance: Criteria for discontinuing or modifying allocated interventions for a given trial participant (eg, drug dose change in response to harms, participant request, or improving/worsening disease).]

Strategies to improve adherence to interventions {11c}

[SPIRIT guidance: Strategies to improve adherence to intervention protocols, and any procedures for monitoring adherence (eg, drug tablet return, laboratory tests).]

Relevant concomitant care permitted or prohibited during the trial {11d}

[SPIRIT guidance: Relevant concomitant care and interventions that are permitted or prohibited during the trial.]

Provisions for post-trial care {30}

[SPIRIT guidance: Provisions, if any, for ancillary and post-trial care, and for compensation to those who suffer harm from trial participation.]

Outcomes {12}

[SPIRIT guidance: Primary, secondary, and other outcomes, including the specific measurement variable (eg, systolic blood pressure), analysis metric (eg, change from baseline, final value, time to event), method of aggregation (eg, median, proportion), and time point for each outcome. Explanation of the clinical relevance of chosen efficacy and harm outcomes is strongly recommended.]

Participant timeline {13}

[SPIRIT guidance: Time schedule of enrolment, interventions (including any run-ins and washouts), assessments, and visits for participants. A schematic diagram is highly recommended (see figure at]

Sample size {14}

[SPIRIT guidance: Estimated number of participants needed to achieve study objectives and how it was determined, including clinical and statistical assumptions supporting any sample size calculations.]

Recruitment {15}

[SPIRIT guidance: Strategies for achieving adequate participant enrolment to reach target sample size.]

Assignment of interventions: allocation

Sequence generation {16a}

[SPIRIT guidance: Method of generating the allocation sequence (eg, computer-generated random numbers), and list of any factors for stratification. To reduce predictability of a random sequence, details of any planned restriction (eg, blocking) should be provided in a separate document that is unavailable to those who enrol participants or assign interventions.]

Concealment mechanism {16b}

[SPIRIT guidance: Mechanism of implementing the allocation sequence (eg, central telephone; sequentially numbered, opaque, sealed envelopes), describing any steps to conceal the sequence until interventions are assigned.]

Implementation {16c}

[SPIRIT guidance: Who will generate the allocation sequence, who will enrol participants, and who will assign participants to interventions.]

Assignment of interventions: Blinding

Who will be blinded {17a}

[SPIRIT guidance: Who will be blinded after assignment to interventions (eg, trial participants, care providers, outcome assessors, data analysts), and how.]

Procedure for unblinding if needed {17b}

[SPIRIT guidance: If blinded, circumstances under which unblinding is permissible, and procedure for revealing a participant’s allocated intervention during the trial.]

Data collection and management

Plans for assessment and collection of outcomes {18a}

[SPIRIT guidance: Plans for assessment and collection of outcome, baseline, and other trial data, including any related processes to promote data quality (eg, duplicate measurements, training of assessors) and a description of study instruments (eg, questionnaires, laboratory tests) along with their reliability and validity, if known. Reference to where data collection forms can be found, if not in the protocol.]

Plans to promote participant retention and complete follow-up {18b}

[SPIRIT guidance: Plans to promote participant retention and complete follow-up, including list of any outcome data to be collected for participants who discontinue or deviate from intervention protocols.]

Data management {19}

[SPIRIT guidance: Plans for data entry, coding, security, and storage, including any related processes to promote data quality (eg, double data entry; range checks for data values). Reference to where details of data management procedures can be found, if not in the protocol.]

Confidentiality {27}

[SPIRIT guidance: How personal information about potential and enrolled participants will be collected, shared, and maintained in order to protect confidentiality before, during, and after the trial.]

Plans for collection, laboratory evaluation and storage of biological specimens for genetic or molecular analysis in this trial/future use {33}

[SPIRIT guidance: Plans for collection, laboratory evaluation, and storage of biological specimens for genetic or molecular analysis in the current trial and for future use in ancillary studies, if applicable.]

Statistical methods

Statistical methods for primary and secondary outcomes {20a}

[SPIRIT guidance: Statistical methods for analysing primary and secondary outcomes. Reference to where other details of the statistical analysis plan can be found, if not in the protocol.]

Interim analyses {21b}

[SPIRIT guidance: Description of any interim analyses and stopping guidelines, including who will have access to these interim results and make the final decision to terminate the trial.]

Methods for additional analyses (e.g. subgroup analyses) {20b}

[SPIRIT guidance: Methods for any additional analyses (eg, subgroup and adjusted analyses).]

Methods in analysis to handle protocol non-adherence and any statistical methods to handle missing data {20c}

[SPIRIT guidance: Definition of analysis population relating to protocol non-adherence (eg, as randomised analysis), and any statistical methods to handle missing data (eg, multiple imputation).]

Plans to give access to the full protocol, participant level-data and statistical code {31c}

[SPIRIT guidance: Plans, if any, for granting public access to the full protocol, participant-level dataset, and statistical code.]

Oversight and monitoring

Composition of the coordinating centre and trial steering committee {5d}

[SPIRIT guidance: Composition, roles, and responsibilities of the coordinating centre, steering committee, endpoint adjudication committee, data management team, and other individuals or groups overseeing the trial, if applicable (see Item 21a for data monitoring committee).]

Composition of the data monitoring committee, its role and reporting structure {21a}

[SPIRIT guidance: Composition of data monitoring committee (DMC); summary of its role and reporting structure; statement of whether it is independent from the sponsor and competing interests; and reference to where further details about its charter can be found, if not in the protocol. Alternatively, an explanation of why a DMC is not needed.]

Adverse event reporting and harms {22}

[SPIRIT guidance: Plans for collecting, assessing, reporting, and managing solicited and spontaneously reported adverse events and other unintended effects of trial interventions or trial conduct.]

Frequency and plans for auditing trial conduct {23}

[SPIRIT guidance: Frequency and procedures for auditing trial conduct, if any, and whether the process will be independent from investigators and the sponsor.]

Plans for communicating important protocol amendments to relevant parties (e.g. trial participants, ethical committees) {25}

[SPIRIT guidance: Plans for communicating important protocol modifications (eg, changes to eligibility criteria, outcomes, analyses) to relevant parties (eg, investigators, REC/IRBs, trial participants, trial registries, journals, regulators).]

Dissemination plans {31a}

[SPIRIT guidance: Plans for investigators and sponsor to communicate trial results to participants, healthcare professionals, the public, and other relevant groups (eg, via publication, reporting in results databases, or other data sharing arrangements), including any publication restrictions.]


[Trials guidance: This should include a discussion of any practical or operational issues involved in performing the study and any issues not covered in other sections.]

Trial status

[Trials guidance: Authors should report the protocol version number and date, the date recruitment began, and the approximate date when recruitment will be completed.]


[Trials guidance: If abbreviations are used in the text they should be defined in the text at first use, and a list of abbreviations should be provided.]


[Trials guidance: All manuscripts must contain the following sections and in this order:]

  • Acknowledgements
  • Authors' contributions
  • Funding
  • Availability of data and material
  • Ethics approval and consent to participate
  • Consent for publication
  • Competing interests
  • Author details
  • Authors’ information (optional)


[Trials guidance: Please acknowledge anyone who contributed towards the article who does not meet the criteria for authorship including anyone who provided professional writing services or materials.

Authors should obtain permission to acknowledge from all those mentioned in the Acknowledgements section.

See our editorial policies for a full explanation of acknowledgements and authorship criteria.

If you do not have anyone to acknowledge, please write "Not applicable" in this section.

Group authorship (for manuscripts involving a collaboration group): if you would like the names of the individual members of a collaboration Group to be searchable through their individual PubMed records, please ensure that the title of the collaboration Group is included on the title page and in the submission system and also include collaborating author names as the last paragraph of the “Acknowledgements” section. Please add authors in the format First Name, Middle initial(s) (optional), Last Name. You can add institution or country information for each author if you wish, but this should be consistent across all authors.

Please note that individual names may not be present in the PubMed record at the time a published article is initially included in PubMed as it takes PubMed additional time to code this information.]

Authors’ contributions {31b}

SPIRIT guidance: [31b] - Authorship eligibility guidelines and any intended use of professional writers.

Trials guidance: The individual contributions of authors to the manuscript should be specified in this section. Guidance and criteria for authorship can be found in our editorial policies.

Please use initials to refer to each author's contribution in this section, for example: "FC analyzed and interpreted the patient data regarding the hematological disease and the transplant. RH performed the histological examination of the kidney, and was a major contributor in writing the manuscript. All authors read and approved the final manuscript."]

Funding {4}

[SPIRIT guidance: Sources and types of financial, material, and other support.

Trials guidance: All sources of funding for the research reported should be declared. The role of the funding body in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript should be declared.]

Availability of data and materials {29}

[SPIRIT guidance: Statement of who will have access to the final trial dataset, and disclosure of contractual agreements that limit such access for investigators.

Trials guidance: All manuscripts must include an ‘Availability of data and materials’ statement. Data availability statements should include information on where data supporting the results reported in the article can be found including, where applicable, hyperlinks to publicly archived datasets analysed or generated during the study. By data we mean the minimal dataset that would be necessary to interpret, replicate and build upon the findings reported in the article. We recognise it is not always possible to share research data publicly, for instance when individual privacy could be compromised, and in such instances data availability should still be stated in the manuscript along with any conditions for access.

Data availability statements can take one of the following forms (or a combination of more than one if required for multiple datasets):

The datasets generated and/or analysed during the current study are available in the [NAME] repository, [PERSISTENT WEB LINK TO DATASETS]The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.All data generated or analysed during this study are included in this published article [and its supplementary information files].The datasets generated and/or analysed during the current study are not publicly available due [REASON WHY DATA ARE NOT PUBLIC] but are available from the corresponding author on reasonable request.Data sharing is not applicable to this article as no datasets were generated or analysed during the current study.The data that support the findings of this study are available from [third party name] but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. Data are however available from the authors upon reasonable request and with permission of [third party name].Not applicable. If your manuscript does not contain any data, please state 'Not applicable' in this section.

More examples of template data availability statements, which include examples of openly available and restricted access datasets, are available here.

BioMed Central also requires that authors cite any publicly available data on which the conclusions of the paper rely in the manuscript. Data citations should include a persistent identifier (such as a DOI) and should ideally be included in the reference list. Citations of datasets, when they appear in the reference list, should include the minimum information recommended by DataCite and follow journal style. Dataset identifiers including DOIs should be expressed as full URLs. For example:

Hao Z, AghaKouchak A, Nakhjiri N, Farahmand A. Global integrated drought monitoring and prediction system (GIDMaPS) data sets. figshare. 2014.

With the corresponding text in the Availability of data and materials statement:

The datasets generated during and/or analysed during the current study are available in the [NAME] repository, [PERSISTENT WEB LINK TO DATASETS].[Reference number] ]

Ethics approval and consent to participate {24}

[SPIRIT guidance: Plans for seeking research ethics committee/institutional review board (REC/IRB) approval.

Trials guidance: Manuscripts reporting studies involving human participants, human data or human tissue must:

include a statement on ethics approval and consent (even where the need for approval was waived)include the name of the ethics committee that approved the study and the committee’s reference number if appropriate

Studies involving animals must include a statement on ethics approval.

See our editorial policies for more information.

If your manuscript does not report on or involve the use of any animal or human data or tissue, please state “Not applicable” in this section.]

Consent for publication {32}

[SPIRIT guidance: Model consent form and other related documentation given to participants and authorised surrogates.]

Trials guidance: If your manuscript contains any individual person’s data in any form (including any individual details, images or videos), consent for publication must be obtained from that person, or in the case of children, their parent or legal guardian. All presentations of case reports must have consent for publication.

You can use your institutional consent form or our consent form if you prefer. You should not send the form to us on submission, but we may request to see a copy at any stage (including after publication).

See our editorial policies for more information on consent for publication.

If your manuscript does not contain data from any individual person, please state “Not applicable” in this section.]

Competing interests {28}

[SPIRIT guidance: Financial and other competing interests for principal investigators for the overall trial and each study site.

Trials guidance: All financial and non-financial competing interests must be declared in this section.

See our editorial policies for a full explanation of competing interests. If you are unsure whether you or any of your co-authors have a competing interest please contact the editorial office.

Please use the authors initials to refer to each authors' competing interests in this section.

If you do not have any competing interests, please state "The authors declare that they have no competing interests" in this section.]


Author details

[Trials guidance: author affiliations].


[Trials guidance: This section is optional. You may choose to use this section to include any relevant information about the author(s) that may aid the reader's interpretation of the article, and understand the standpoint of the author(s). This may include details about the authors' qualifications, current positions they hold at institutions or societies, or any other relevant background information. Please refer to authors using their initials. Note this section should not be used to describe any competing interests.]



[Trials guidance: Examples of the Vancouver reference style are shown below.]

See our editorial policies for author guidance on good citation practice

Web links and URLs: All web links and URLs, including links to the authors' own websites, should be given a reference number and included in the reference list rather than within the text of the manuscript. They should be provided in full, including both the title of the site and the URL, as well as the date the site was accessed, in the following format: The Mouse Tumor Biology Database. Accessed 20 May 2013. If an author or group of authors can clearly be associated with a web link, such as for weblogs, then they should be included in the reference.

Example reference style:

Article within a journal

Smith JJ. The world of science. Am J Sci. 1999;36:234-5.

Article within a journal (no page numbers)

Rohrmann S, Overvad K, Bueno-de-Mesquita HB, Jakobsen MU, Egeberg R, Tjønneland A, et al. Meat consumption and mortality - results from the European Prospective Investigation into Cancer and Nutrition. BMC Medicine. 2013;11:63.

Article within a journal by DOI

Slifka MK, Whitton JL. Clinical implications of dysregulated cytokine production. Dig J Mol Med. 2000; doi:10.1007/s801090000086.

Article within a journal supplement

Frumin AM, Nussbaum J, Esposito M. Functional asplenia: demonstration of splenic activity by bone marrow scan. Blood 1979;59 Suppl 1:26-32.

Book chapter, or an article within a book

Wyllie AH, Kerr JFR, Currie AR. Cell death: the significance of apoptosis. In: Bourne GH, Danielli JF, Jeon KW, editors. International review of cytology. London: Academic; 1980. p. 251-306.

OnlineFirst chapter in a series (without a volume designation but with a DOI)

Saito Y, Hyuga H. Rate equation approaches to amplification of enantiomeric excess and chiral symmetry breaking. Top Curr Chem. 2007. doi:10.1007/128_2006_108.

Complete book, authored

Blenkinsopp A, Paxton P. Symptoms in the pharmacy: a guide to the management of common illness. 3rd ed. Oxford: Blackwell Science; 1998.

Online document

Doe J. Title of subordinate document. In: The dictionary of substances and their effects. Royal Society of Chemistry. 1999. of subordinate document. Accessed 15 Jan 1999.

Online database

Healthwise Knowledgebase. US Pharmacopeia, Rockville. 1998. Accessed 21 Sept 1998.

Supplementary material/private homepage

Doe J. Title of supplementary material. 2000. Accessed 22 Feb 2000.

University site

Doe, J: Title of preprint. (1999). Accessed 25 Dec 1999.

FTP site

Doe, J: Trivial HTTP, RFC2169. (1999). Accessed 12 Nov 1999.

Organization site

ISSN International Centre: The ISSN register. (2006). Accessed 20 Feb 2007.

Dataset with persistent identifier

Zheng L-Y, Guo X-S, He B, Sun L-J, Peng Y, Dong S-S, et al. Genome data from sweet and grain sorghum (Sorghum bicolor). GigaScience Database. 2011.

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