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The TIDieR checklist (Template for Intervention Description and Replication) is a 12-item reporting guideline that specifies what a study must document about an intervention so that another researcher — or a clinician trying to implement it — can actually reproduce it. It was published in the BMJ in 2014 by Tammy Hoffmann, Paul Glasziou, Isabelle Boutron and colleagues (Hoffmann et al., BMJ 2014;348:g1687) and is maintained under the EQUATOR Network.
Unlike CONSORT or STROBE, which cover a whole study report, TIDieR covers one specific, often-skimped part of it: the description of the intervention itself. It applies to drug trials, but was written to work for any intervention — behavioural, educational, surgical, digital, or a complex multi-component programme — and it applies equally to the intervention arm and to whatever the control/comparison arm actually received. “Usual care” is explicitly called out in the source paper as not a sufficient description of a control condition.
The 12-item TIDieR checklist
This is the full checklist, item name and required content, as published. Use it as a drafting template: work through each row for both the intervention and the comparison condition.
| # | Item | What to report |
|---|---|---|
| 1 | Brief name | The name or a short phrase describing the intervention. |
| 2 | Why | The rationale, theory, or goal of the essential elements of the intervention. |
| 3 | What (materials) | Physical or informational materials used, including those given to participants or used to train providers, and where they can be accessed. |
| 4 | What (procedures) | Each procedure, activity, and/or process used in the intervention, including support activities. |
| 5 | Who provided | For each category of provider (e.g. psychologist, nurse), their expertise, background, and any specific training given. |
| 6 | How | The mode(s) of delivery (face to face, phone, internet, etc.) and whether delivered individually or in a group. |
| 7 | Where | The type of location(s) where the intervention occurred, including any necessary infrastructure. |
| 8 | When and how much | Number of times delivered, over what period, including number of sessions, schedule, duration, intensity or dose. |
| 9 | Tailoring | If personalised, titrated, or adapted for individual participants: what, why, when, and how. |
| 10 | Modifications | If the intervention was modified during the study: what changed, why, when, and how. |
| 11 | How well (planned) | If adherence/fidelity was assessed as planned: how, by whom, and any strategies used to maintain or improve fidelity. |
| 12 | How well (actual) | If adherence/fidelity was assessed: the extent to which the intervention was actually delivered as planned. |
Last verified against the primary BMJ publication (DOI 10.1136/bmj.g1687, PMID 24609605): 2026-08-16.
Why this checklist exists
Poor intervention reporting is one of the most common, and most consequential, gaps in published health research. A trial can be perfectly designed and perfectly reported on every other dimension — randomisation, blinding, outcomes, statistics — and still be useless to a reader who wants to replicate or implement the intervention, because “patients received standard physiotherapy” or “participants attended counselling sessions” doesn’t say what actually happened. TIDieR’s authors developed the checklist specifically to close that gap, building on earlier, narrower attempts (such as an item added to the CONSORT 2010 checklist) and piloting the explanation-and-elaboration document with researchers actively writing intervention papers before publishing the final version.
The checklist deliberately does not duplicate what CONSORT, SPIRIT, or STROBE already require about population, outcomes, and other methodological features of a study. Framed against the PICO structure (Population, Intervention, Comparison, Outcome), TIDieR covers only the I and C: the intervention and comparison elements. It is meant to be used inside a CONSORT-reported trial or a SPIRIT-written protocol, not instead of them.
Who requires or recommends TIDieR
- CONSORT 2010. Item 5 of the CONSORT statement (interventions) directs authors to TIDieR for the level of detail expected.
- SPIRIT 2013. The equivalent protocol item for describing planned interventions also points authors to TIDieR.
- Systematic reviews and evidence syntheses. Reviewers assessing “what was the intervention, exactly?” across included studies use TIDieR as a data-extraction frame, independent of whether the original trial authors used it.
- Individual journals. A growing number of clinical, health-services, and behavioural-science journals list TIDieR in their Instructions for Authors as a required or recommended checklist whenever a submission describes an intervention, in addition to whichever design-level guideline (CONSORT, STROBE, etc.) applies. Always check your specific target journal — requirements are set journal by journal, not universally.
How to use TIDieR when writing a methods section
- Draft against the 12 items directly, one at a time, rather than writing narrative prose first and checking it afterward — it’s much easier to catch a missing item (Tailoring and Modifications are the two most commonly skipped) before the section is written than after.
- Repeat the exercise for the comparison/control condition. The published paper is explicit that “usual care” is not an adequate description; describe what the control group actually received with the same rigor as the intervention group.
- Combine items where natural. The guide notes items can be merged into a single sentence where that reads more naturally — materials (item 3) and procedures (item 4) are commonly combined. The requirement is completeness, not that each item gets its own paragraph.
- Point to supplementary material for bulk content. Training manuals, session scripts, or intervention materials that don’t fit in the word count belong in a supplementary appendix or a public repository, with the location cited under item 3.
- Report items 11 and 12 even when the answer is “not assessed.” Fidelity/adherence reporting is one of the checklist’s most frequently omitted elements; stating explicitly that it wasn’t measured is more transparent than silence.
TIDieR vs. other reporting guidelines
TIDieR is scoped narrowly on purpose. It is not a substitute for a full study-reporting guideline — use it alongside the one that matches your design:
| Guideline | Scope | Relationship to TIDieR |
|---|---|---|
| CONSORT | Full report of a randomised controlled trial | CONSORT’s intervention item (item 5) refers authors to TIDieR for the required level of detail. |
| SPIRIT 2013 | Trial protocol, written before the trial starts | Same relationship as CONSORT, applied at the protocol stage. |
| STROBE | Observational studies (cohort, case-control, cross-sectional) | TIDieR applies if the observational study evaluates an exposure that functions like an intervention (e.g. a policy or programme rollout). |
| PRISMA 2020 | Systematic reviews and meta-analyses | Reviewers can use TIDieR’s 12 items as an extraction template for describing interventions across the included studies. |
For a broader map of which guideline applies to which study design, see CASRAI’s EQUATOR Network guide. For general guidance on writing a reproducible methods section, see Writing the Methods Section So It Can Be Reproduced.
Frequently asked questions
Is there a TIDieR template or form I can fill in?
The checklist itself functions as the template: the 12 items above, in table form, are what most authors use directly as a drafting or data-extraction grid. The EQUATOR Network hosts the official checklist and the full explanation-and-elaboration paper, which gives worked examples for every item, at its TIDieR guideline page.
Does TIDieR replace CONSORT or STROBE?
No. TIDieR only covers the intervention-description portion of a study report. It is designed to be used alongside a full design-level guideline (CONSORT for RCTs, STROBE for observational studies, SPIRIT for protocols), not instead of one.
Does TIDieR apply outside clinical trials?
Yes. The checklist was written to cover any intervention — behavioural, educational, digital, surgical, or a complex multi-component programme — not only pharmacological ones, and it applies to non-randomised and quasi-experimental intervention studies as well as RCTs.
Do I need to report all 12 items even for a simple intervention?
The checklist authors note that most items are relevant even for apparently simple interventions such as a single drug dose, which are often still poorly described in practice. Items can be combined into fewer sentences where that’s natural, but each should be addressed somewhere in the report.
What’s the difference between “how well (planned)” and “how well (actual)”?
Item 11 covers what fidelity/adherence monitoring was planned and how (if any); item 12 reports what was actually observed — the extent to which the intervention was delivered as intended. A study can plan fidelity monitoring (item 11) and still need to report the actual result (item 12), or explicitly state that adherence wasn’t assessed.
Further reading: STROBE Checklist — The complete 22-item STROBE checklist for reporting cohort, case-control, and cross-sectional studies, organized by section, with the four items that differ by design.
