A randomized controlled trial (or randomized control trial; RCT) is a type of scientific (often medical) experiment that aims to reduce certain sources of bias when testing the effectiveness of new treatments; this is accomplished by randomly allocating subjects to two or more groups, treating them differently, and then comparing them with respect to a measured response. (Wikipedia)
Unsure if your study is an randomized trial (RT) or RCT? Look at the methods. If you use the phrase "subjects were randomly assigned to..." then your study is a RT or RCT. Substituting the word "trial" with "experiment" does not exempt the trial from registration requirements. Any RT/RCT is by definition an experiment. And because you chose to publish your paper in a medical journal, any outcomes you are looking at are likely "health outcomes", even if they are indirect (e.g. behavior change or educational outcomes).
In accordance with ICMJE recommendations (International Committee of Medical Journal Editors), RTs and RCTs (but not other trial designs) must be prospectively registered (before the trial starts and subjects are enrolled) in a WHO accredited trial registry such as clinicaltrials.gov.
The ICMJE defines a clinical trial as any research project that prospectively assigns people or a group of people to an intervention, with or without concurrent comparison or control groups, to study the cause-and-effect relationship between a health-related intervention and a health outcome. Health-related interventions are those used to modify a biomedical or health-related outcome; examples include drugs, surgical procedures, devices, behavioural treatments, educational programs, dietary interventions, quality improvement interventions, and process-of-care changes. Health outcomes are any biomedical or health-related measures obtained in patients or participants, including pharmacokinetic measures and adverse events. (ICMJE)
Purely observational studies (those in which the assignment of the medical intervention is not at the discretion of the investigator) do not require registration. JMIR does not currently require registration for non-randomized studies (although registration as registered report, i.e. publishing a protocol before data are collected, is best practice and highly encouraged for any project), i.e. only randomized studies require registration.
A frequent misunderstanding is that a "clinical" trial only refers to studies that take place in a hospital environment or involve pharmaceuticals. This is not the case. Any randomized controlled trial (defined as randomizing people into different groups) needs to be registered (best done through protocol publication) before data are collected, i.e. the first subject is enrolled.
JMIR authors should be reminded that mobile and web-based interventions as well as devices are usually targeting behavioural or other outcomes, and must usually be registered.
Registration of research is free, does not take more than a few minutes, and is best practice (not only for RCTs - ideally you should publish/register any research project prospectively, see Why should I publish my protocol or grant proposal? ). This is not something we invented, but a consensus of medical editors and the research community.
The purpose of trial registration is to prevent selective publication and selective reporting of research outcomes, to prevent unnecessary duplication of research effort, to help patients and the public know what trials are planned or ongoing into which they might want to enroll, and to help give ethics review boards considering approval of new studies a view of similar work and data relevant to the research they are considering.(ICMJE)
For reports of trials, please mention the ClinicalTrials.gov registration identifier, the International Standard Randomized Controlled Trial Number (ISRCTN) and/or the International Registered Report Identifier (IRRID), or a comparable trial identifier at the end of the abstract ("Trial Registration: ClinicalTrials.gov NCT123456"), as well as when you first mention the trial in the manuscript. Protocols do not have to be registered although we highly recommend it and the (separate) results paper of the study can only be published if it carries a registration identifier and if it was prospectively registered (before enrolment of participants).
When mentioning related trials (e.g. in the Introduction or Methods section) the trial registration number should also be added in brackets.
ICMJE member journals require, as a condition of consideration for publication, registration in a public trials registry at or before the onset of patient enrollment. This policy applies to any trial which started enrollment after July 1, 2005.
JMIR authors must add an explanation to the methods section of their manuscript if a RCT meeting these criteria has not been registered. The JMIR editor reserves the right to reject any paper without trial registration without any further consideration or peer-review, or to add a "Notice of Editorial Concern" (see below).
If authors neglect prospective registration, this may render the paper unpublishable in most journals.
JMIR can offer the following exceptions:
- the paper can be transferred to JMIR Res Protoc or JMIR Formative Res or, as formative/pilot/feasibility studies do not require registration
- "If the purpose is to examine the effect only on the providers rather than patients (for example, provider knowledge or attitudes), then registration is not necessary" (ICMJE). JMIR journals also recognize graduate/undergraduate (medical, psychology etc) students (but not elementary/middle/high school students) or other volunteer subjects as a valid exception, although when in doubt, authors should err on the side of caution and register the trial prospectively
- if a protocol has been published (for example submitted to JMIR Res Protoc) before enrolment, then we may also waive the trial registration mandate, because publication of the protocol is equivalent to trial registration (you will receive a International Registered Report Identifier (IRRID) and meets all of the purposes listed above regarding transparency and prevention of "outcome creep" (see also Why should I publish my protocol or grant proposal?)
- in some cases we may accept letters from the IRB/REB confirming that the protocol/design of the submitted study is identical with what the IRB/REB assessed when providing approval before the trial started
- JMIR is interested in reducing publication bias, thus, as recommended by the ICMJE, JMIR editors may grant other exceptions on a case-by-case basis, if the potential for bias was low. However, authors must explain why the trial was not prospectively registered, and need to register it retrospectively. This should be explicitly mentioned in the methods part of the paper. The editor reserves the right to add a notice of editorial concern to the paper (see below). The ICMJE recommendation on exceptions reads as follows:
Editors may consider whether the circumstances involved in a failure to appropriately register a clinical trial were likely to have been intended to or resulted in biased reporting. If an exception to prospective registration is made, trials must be registered [retrospectively] and the authors should indicate in the publication when registration was completed and why it was delayed. Editors should publish a statement indicating why an exception was allowed. The ICMJE emphasizes that such exceptions should be rare, and that authors failing to prospectively register a trial risk its admissibililty to our journals.
Starting in 2017, JMIR will add a "Editorial Notice" to any paper where the RCT has not been prospectively registered (i.e. the editor made an exception, as specified above under point 5).
Sample text (to be published underneath the "Conflict of Interest" section):
Editorial notice: This randomized study was [only retrospectively | not] registered, explained by authors with (insert reasons here, e.g. "technical problems"). The editor granted an exception from ICMJE rules mandating prospective registration of randomized trials, because the risk of bias appears low and the study was considered formative, guiding the development of the application [or other reasons for the exception, as argued by the authors]. However, readers are advised to carefully assess the validity of any potential explicit or implicit claims related to primary outcomes or effectiveness, as retrospective registration does not prevent authors from changing their outcome measures retrospectively.
To be clear, any RCT still needs to be retrospectively registered if an exception under point 5 is granted, and the trial registration number needs to be mentioned in the abstract, followed by the phrase "(retrospectively registered)". "Retrospectively" means any registration that occurred after the first participants was enrolled.
Feasibility/pilot/formative studies are usually not published in our impact-factor journals with IF3.0 (JMIR, JMIR mHealth, JMIR Med Inform, JMIR Mental Health, JMIR Serious Games), rather they should be transferred to JMIR Formative Res, but if they are, retrospective registration is required.
We do not insist on retrospective registration in the case of clear formative studies published in JMIR Formative Res (JFR) or JMIR Res Protoc (JRP), but we strongly recommend it. The editorial notice above is usually still added for clarity.
A trial registration is different from a registered report. See What is a Registered Report?
A trial registration is still required, even if a RRID is assigned. It may however be a "mitigating" circumstance if a RRID exists and the trial wasn't registered (i.e. we are more prone to make an exception).