Trial overview — Parallel-group randomized trial

Question

Define the population, assigned interventions, outcome and intended treatment effect.

Protocol and approvals

Prespecify design, estimands, analysis, safety oversight and required ethics and regulatory approvals.

Register

Register the trial before enrolling the first participant in an eligible public trial registry; record its name and identifier.

Recruit

Apply eligibility and approved consent procedures, documenting screening and enrollment.

Randomize

Generate the allocation sequence and conceal upcoming assignments; define blinding separately.

Treat and follow

Deliver assigned care and continue relevant outcome and safety assessments after treatment changes.

Finalize data

Resolve queries and derivations; define overlapping analysis populations and preserve the audit trail before unblinding.

Analyze according to plan

Estimate the planned treatment effect with multiplicity, missingness and sensitivity methods specified in advance.

Report

Report allocation, follow-up, analysis, harms and protocol changes with CONSORT and the registered protocol.

Trial overview

End flow

Protocol and decision register

Record the protocol, approvals and registration where applicable. Preserve planned decisions and amendments separately from results.

Protocol and rationale evidence

Attach the dated protocol, approvals and amendments. A clinical trial registry publicly records the trial plan, such as ClinicalTrials.gov or an eligible WHO primary registry such as ISRCTN. Record the registry name, identifier and registration date before first enrollment. WHO ICTRP is a search platform, not itself a registry. Registration does not imply randomization.