All clinical interventional trials must be registered prospectively, before enrollment of the first participant as a condition of consideration for publication. Trial registration records must be available in a primary register of the WHO International Clinical Trials Registry Platform (ICTRP), in, or in any publicly accessible database that meets the minimum 24-item trial registration dataset. For more information on clinical trials, please see our Clinical Research guidelines.

For non-clinical confirmatory research, we strongly encourage study preregistation with an analysis plan. We ask that authors indicate at the time of submission if any of the work reported in their manuscript was preregistered. If there was no preregistration of any study, this must be declared in the Methods section for transparency. Conversely, if any of the reported studies was preregistered, authors must provide an active link to the preregistration in the Methods section and state the date of preregistration. Authors must disclose all deviations from the preregistered protocol and explain the rationale for deviation (e.g., flaw, feasibility, suboptimality). In cases of deviation from the preregistered analysis plan for reasons other than fundamental flaw or feasibility, the originally planned analyses must also be reported.

Editors and reviewers examine adherence to the protocol and transparent disclosure of deviations. Manuscripts reporting preregistered research will not be accepted for publication until they meet these requirements.