1. Introduction
2. Intent of CONSORT 2010
Section/Topic | Item No | Checklist item | Reported on page No |
---|---|---|---|
Title and abstract | |||
1a | Identification as a randomised trial in the title | ||
1b | Structured summary of trial design, methods, results, and conclusions (for specific guidance see CONSORT for abstracts 21 , 31 ) | ||
Introduction | |||
Background and objectives | 2a | Scientific background and explanation of rationale | |
2b | Specific objectives or hypotheses | ||
Methods | |||
Trial design | 3a | Description of trial design (such as parallel, factorial) including allocation ratio | |
3b | Important changes to methods after trial commencement (such as eligibility criteria), with reasons | ||
Participants | 4a | Eligibility criteria for participants | |
4b | Settings and locations where the data were collected | ||
Interventions | 5 | The interventions for each group with sufficient details to allow replication, including how and when they were actually administered | |
Outcomes | 6a | Completely defined pre-specified primary and secondary outcome measures, including how and when they were assessed | |
6b | Any changes to trial outcomes after the trial commenced, with reasons | ||
Sample size | 7a | How sample size was determined | |
7b | When applicable, explanation of any interim analyses and stopping guidelines | ||
Randomisation: | |||
Sequence generation | 8a | Method used to generate the random allocation sequence | |
8b | Type of randomisation; details of any restriction (such as blocking and block size) | ||
Allocation concealment mechanism | 9 | Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned | |
Implementation | 10 | Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions | |
Blinding | 11a | If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how | |
11b | If relevant, description of the similarity of interventions | ||
Statistical methods | 12a | Statistical methods used to compare groups for primary and secondary outcomes | |
12b | Methods for additional analyses, such as subgroup analyses and adjusted analyses | ||
Results | |||
Participant flow (a diagram is strongly recommended) | 13a | For each group, the numbers of participants who were randomly assigned, received intended treatment, and were analysed for the primary outcome | |
13b | For each group, losses and exclusions after randomisation, together with reasons | ||
Recruitment | 14a | Dates defining the periods of recruitment and follow-up | |
14b | Why the trial ended or was stopped | ||
Baseline data | 15 | A table showing baseline demographic and clinical characteristics for each group | |
Numbers analysed | 16 | For each group, number of participants (denominator) included in each analysis and whether the analysis was by original assigned groups | |
Outcomes and estimation | 17a | For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) | |
17b | For binary outcomes, presentation of both absolute and relative effect sizes is recommended | ||
Ancillary analyses | 18 | Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing pre-specified from exploratory | |
Harms | 19 | All important harms or unintended effects in each group (for specific guidance see CONSORT for harms [28] ) | |
Discussion | |||
Limitations | 20 | Trial limitations, addressing sources of potential bias, imprecision, and, if relevant, multiplicity of analyses | |
Generalisability | 21 | Generalisability (external validity, applicability) of the trial findings | |
Interpretation | 22 | Interpretation consistent with results, balancing benefits and harms, and considering other relevant evidence | |
Other information | |||
Registration | 23 | Registration number and name of trial registry | |
Protocol | 24 | Where the full trial protocol can be accessed, if available | |
Funding | 25 | Sources of funding and other support (such as supply of drugs), role of funders |
3. Background to CONSORT
4. Development of CONSORT 2010
5. Changes in CONSORT 2010
- •We simplified and clarified the wording, such as in items 1, 8, 10, 13, 15, 16, 18, 19, and 21
- •We improved consistency of style across the items by removing the imperative verbs that were in the 2001 version
- •We enhanced specificity of appraisal by breaking some items into sub-items. Many journals expect authors to complete a CONSORT checklist indicating where in the manuscript the items have been addressed. Experience with the checklist noted pragmatic difficulties when an item comprised multiple elements. For example, item 4 addresses eligibility of participants and the settings and locations of data collection. With the 2001 version, an author could provide a page number for that item on the checklist, but might have reported only eligibility in the paper, for example, and not reported the settings and locations. CONSORT 2010 relieves obfuscations and forces authors to provide page numbers in the checklist for both eligibility and settings
- Item 1b (title and abstract)—We added a sub-item on providing a structured summary of trial design, methods, results, and conclusions and referenced the CONSORT for abstracts article [[21]]
- Item 2b (introduction)—We added a new sub-item (formerly item 5 in CONSORT 2001) on “Specific objectives or hypotheses”
- Item 3a (trial design)—We added a new item including this sub-item to clarify the basic trial design (such as parallel group, crossover, cluster) and the allocation ratio
- Item 3b (trial design)—We added a new sub-item that addresses any important changes to methods after trial commencement, with a discussion of reasons
- Item 4 (participants)—Formerly item 3 in CONSORT 2001
- Item 5 (interventions)—Formerly item 4 in CONSORT 2001. We encouraged greater specificity by stating that descriptions of interventions should include “sufficient details to allow replication” [[3]]
- Item 6 (outcomes)—We added a sub-item on identifying any changes to the primary and secondary outcome (endpoint) measures after the trial started. This followed from empirical evidence that authors frequently provide analyses of outcomes in their published papers that were not the prespecified primary and secondary outcomes in their protocols, while ignoring their prespecified outcomes (that is, selective outcome reporting) [4,22]. We eliminated text on any methods used to enhance the quality of measurements
- Item 9 (allocation concealment mechanism)—We reworded this to include mechanism in both the report topic and the descriptor to reinforce that authors should report the actual steps taken to ensure allocation concealment rather than simply report imprecise, perhaps banal, assurances of concealment
- Item 11 (blinding)—We added the specification of how blinding was done and, if relevant, a description of the similarity of interventions and procedures. We also eliminated text on “how the success of blinding (masking) was assessed” because of a lack of empirical evidence supporting the practice as well as theoretical concerns about the validity of any such assessment [23,24]
- Item 12a (statistical methods)—We added that statistical methods should also be provided for analysis of secondary outcomes
- Sub-item 14b (recruitment)—Based on empirical research, we added a sub-item on “Why the trial ended or was stopped” [[25]]
- Item 15 (baseline data)—We specified “A table” to clarify that baseline and clinical characteristics of each group are most clearly expressed in a table
- Item 16 (numbers analysed)—We replaced mention of “intention to treat” analysis, a widely misused term, by a more explicit request for information about retaining participants in their original assigned groups [[26]]
- Sub-item 17b (outcomes and estimation)—For appropriate clinical interpretability, prevailing experience suggested the addition of “For binary outcomes, presentation of both relative and absolute effect sizes is recommended” [[27]]
- Item 19 (harms)—We included a reference to the CONSORT paper on harms [[28]]
- Item 20 (limitations)—We changed the topic from “Interpretation” and supplanted the prior text with a sentence focusing on the reporting of sources of potential bias and imprecision
- Item 22 (interpretation)—We changed the topic from “Overall evidence.” Indeed, we understand that authors should be allowed leeway for interpretation under this nebulous heading. However, the CONSORT Group expressed concerns that conclusions in papers frequently misrepresented the actual analytical results and that harms were ignored or marginalised. Therefore, we changed the checklist item to include the concepts of results matching interpretations and of benefits being balanced with harms
- Item 23 (registration)—We added a new item on trial registration. Empirical evidence supports the need for trial registration, and recent requirements by journal editors have fostered compliance [[29]]
- Item 24 (protocol)—We added a new item on availability of the trial protocol. Empirical evidence suggests that authors often ignore, in the conduct and reporting of their trial, what they stated in the protocol [4,22]. Hence, availability of the protocol can instigate adherence to the protocol before publication and facilitate assessment of adherence after publication
- Item 25 (funding)—We added a new item on funding. Empirical evidence points toward funding source sometimes being associated with estimated treatment effects [[30]]
6. Implications and limitations
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Footnotes
The CONSORT statement is used worldwide to improve the reporting of randomised controlled trials. Kenneth Schulz and colleagues describe the latest version, CONSORT 2010, which updates the reporting guideline based on new methodological evidence and accumulating experience.
In order to encourage dissemination of the CONSORT 2010 Statement, this article is freely accessible on bmj.com and will also be published in the Lancet, Obstetrics and Gynecology, PloS Medicine, Annals of Internal Medicine, Open Medicine, Journal of Clinical Epidemiology, BMC Medicine, and Trials. The authors jointly hold the copyright for this article. For details on further use, see the CONSORt website (www.consort-statement.org).
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non-commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/and http://creativecommons.org/licenses/by-nc/2.0/legalcode.
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