The CONSORT checklist, item by item

CONSORT — the Consolidated Standards of Reporting Trials — provides the CONSORT 2025 reporting checklist and flow diagram ↗ for randomized trials. This walkthrough follows the official expanded 2025 checklist ↗. Many trial-publishing journals require a completed checklist and a flow diagram at submission, and an editor can confirm in minutes whether they are present. Complete reporting helps readers assess the trial's design, analysis, and interpretation. Check the current checklist and the journal's requirements before submission.

Identify the trial as randomized in the title (item 1a) and report itsregistration (item 2), including the registration date. Give access to the protocol and statistical analysis plan (item 3). Registration provides a dated record to compare with the report; describe important changes after the trial began and explain them (item 10).

Specify the primary and secondary outcomes (item 14). Define the measurements, analysis metrics, aggregation, and time points. A trial may have more than one primary outcome. If the trial was designed using the estimands framework, describe the objectives in that framework (item 7), including the estimand—the treatment effect the analysis aims to estimate. Explain how statistical methods address multiplicity where applicable (item 21a). Describe the trial design and allocation ratio (item 9).

State how the sample size was determined (item 16a) — the effect you powered to detect, and the assumptions behind it.

Self-check. Do the reported primary outcome(s), measurements, and time points match the dated plan? Explain any changes and identify analyses that were not prespecified.

Describe sequence generation and restrictions (items 17a–b), allocation concealment (item 18), access to the allocation sequence during implementation (item 19), and blinding (items 20a–b). Allocation concealment means the person enrolling a participant cannot foresee the next assignment; describe the safeguards used.

Self-check. Can readers identify the unit of randomization and how assignment was concealed? Planned cluster allocation by household or clinic can be appropriate when the design and analysis account for clustering. Distinguish that design from departures from an individual-randomization protocol, as discussed in a worked review of corrected PREDIMED.

The participant flow diagram (items 22a–b) shows allocation, receipt of the intervention, analysis of the primary outcome, and losses or exclusions with reasons for each group.Define each analysis set and the group used (item 21b) and explain missing-data handling (item 21c). Match the analysis to the trial question and estimand. Intention-to-treat and per-protocol analyses answer different questions; noninferiority trials may need both, with explicit assumptions and attention to exclusions and nonadherence.

For each primary and secondary outcome, report group results, analysis counts, available-data counts, and the effect estimate with its precision (item 26), not a bare p-value.

Self-check. Do the arm totals in your flow diagram reconcile with the numbers analyzed in every table? Counts that do not add up are a deterministic catch — the kind recomputed automatically, as in how journals catch statistical errors.

Describe how harms were defined and assessed (item 15) and report harms or unintended events by group (item 27). Discuss limitations (item 30), including potential bias, imprecision, generalizability, and relevant multiplicity. Interpret results consistently (item 29), balancing benefits and harms and considering other evidence. Clearly distinguish primary results from secondary or exploratory findings.

Self-check. Does the abstract accurately describe the primary outcome(s) and uncertainty? For cluster, noninferiority, pilot, and feasibility trials, use relevant CONSORT extensions alongside the current core checklist and check the journal's requested version.

Complete the official CONSORT 2025 checklist and draw the flow diagram before submission. RigorMD assesses reporting completeness against CONSORT as one of seven scored domains. Its two independent appraisers also examine whether the primary analysis follows the trial plan and whether subgroup conclusions are supported. Separate numerical checks recalculate statistics when the manuscript supplies the required inputs. Complete reporting and an appropriate analysis are different questions; the report does not replace peer review or a statistician's input on design.

See a full sample report →, read how the engine works, or review pricing — the pre-submission review is $99. For other designs, see the STROBE, TRIPOD, and PRISMA walkthroughs.