Which studies require registration

HNCBT requires prospective registration of clinical trials: research that prospectively assigns people to a health-related intervention to evaluate a health outcome. This includes early-phase and non-randomized interventional studies when they meet that definition. Observational studies should be identified accurately and must not be described as trials merely because data are collected prospectively.

Registry and timing

Register before the first participant is enrolled in an acceptable WHO ICTRP primary registry or ClinicalTrials.gov, consistent with the ICMJE clinical trial recommendations. Provide the registry name, identifier, registration date and first-enrollment date. Include the identifier in the abstract and a working link in the manuscript.

If registration was delayed or absent, disclose this at submission and explain the chronology. Retrospective registration must not be described as prospective. Such manuscripts require specific editorial consideration and may be declined; registration after the event does not erase the risk of selective reporting.

Protocol and outcomes

Supply the protocol and statistical analysis plan relevant to the reported results. Explain changes to eligibility, endpoints or analyses and identify prespecified and post hoc work. The registry, protocol, abstract and article should be consistent; discrepancies must be explained. Report participant flow, harms, treatment exposure and the study’s limitations, using CONSORT and relevant extensions or another appropriate design-specific guideline.

Data-sharing statement

Trial reports must state whether de-identified individual participant data will be shared, which data and documents are included, when and for how long they will be available, and the access conditions and mechanism. “Undecided” is insufficient. The published statement should match the registered plan, with changes explained and the registry updated as appropriate.

Ethics and secondary analyses

Registration is separate from ethical approval and informed consent. Both must be addressed under Human Research Ethics. Secondary reports must cite the trial and primary publication, explain the distinct question and disclose related analyses. Authors must not divide results into overlapping reports without a clear scientific reason and transparent cross-reference.