EditverseLay summaries of trial results under the EU Clinical Trials Regulation
The ten Annex V elements of Regulation (EU) No 536/2014, the one-year deadline, the readability targets in the EU expert group recommendations, and a CSR paragraph rewritten for lay readers.
Key points
- Article 37(4) of Regulation (EU) No 536/2014 requires the sponsor to submit a summary of results to the EU database within one year of the end of the trial in all Member States concerned, whatever the outcome, accompanied by a summary written for laypersons.
- Annex V lists ten elements for the lay summary, from trial identification to where more information can be found.
- The EU expert group recommendations (version 2, February 2018) advise writing for literacy proficiency level 2 to 3, give readability tests for English, and ask for absolute numbers, everyday words and a neutral, non-promotional tone.
- The lay summary is drafted from the clinical study report and the technical results summary. It should not copy their text, and it must not say more, or less, than they support.
The legal requirement
Regulation (EU) No 536/2014 on clinical trials on medicinal products for human use sets the obligation in Article 37(4).1 Four points matter to whoever plans the writing.
- Who and what. The sponsor submits to the EU database a summary of the results of the clinical trial, with content set out in Annex IV, accompanied by a summary written in a manner that is understandable to laypersons, with content set out in Annex V.
- When. Within one year from the end of the trial in all Member States concerned, irrespective of the outcome.
- Later submission. Where, for scientific reasons detailed in the protocol, it is not possible to submit within a year, the summary is submitted as soon as it is available, and the protocol must state when and give a justification.
- Interim data. Under Article 37(8), where the protocol provides for an intermediate data analysis date before the end of the trial and those results are available, a summary of them is submitted within one year of that date.
The same paragraph covers the clinical study report: where the trial was intended to support a marketing authorisation, the applicant submits the report to the EU database within 30 days after the authorisation is granted, the procedure is completed or the application is withdrawn.1
The ten Annex V elements
Annex V is a numbered list. The middle column paraphrases the Regulation; the third shows the plain-question headings that the EU expert group recommendations suggest sponsors use, where the document gives them, and working notes on source.12
| No. | Element in Annex V | How to present it | Source in the trial documents |
|---|---|---|---|
| 1 | Clinical trial identification: title of the trial, protocol number, EU trial number and other identifiers. | A short plain title first, then the full title and the identifiers. | Protocol title page; registry records. |
| 2 | Name and contact details of the sponsor. | Organisation name and a public contact point. | EU database record. |
| 3 | General information about the trial: where and when it was conducted, its main objectives and an explanation of the reasons for conducting it. | Headings such as "When was this study done?" and "What was the main objective of this study?". Explain why the comparator was chosen. | Protocol sections on rationale and objectives; study dates. |
| 4 | Population of subjects: number included in the Member State concerned, in the Union and in third countries; age group and gender breakdown; inclusion and exclusion criteria. | Whole numbers; the main criteria only, in everyday words. | Disposition and demographic tables; protocol eligibility section. |
| 5 | Investigational medicinal products used. | What each group received, how and for how long. Explain placebo, randomisation and blinding in a sentence each if they were used. | Protocol treatment section. |
| 6 | Description of adverse reactions and their frequency. | Numbers of participants out of the total in each group, with percentages; serious reactions stated separately. | Safety tables. |
| 7 | Overall results of the trial. | Primary endpoint results by group, plus any safety data important to the overall result; refer to the technical summary for the full list of endpoints. | Primary efficacy table; technical results summary. |
| 8 | Comments on the outcome of the trial. | What the result means and what it does not; limits of a single trial. | Report discussion and conclusions. |
| 9 | Indication whether follow-up clinical trials are foreseen. | A plain statement, including "none planned". | Development plan. |
| 10 | Indication where additional information could be found. | EU database record, registry numbers, sponsor web page. | Registry records. |
Readability targets in the EU recommendations
The document "Summaries of Clinical Trial Results for Laypersons" contains the recommendations of the expert group on clinical trials for the implementation of the Regulation. Version 2 was published in February 2018 and is listed in EudraLex Volume 10, Chapter V, alongside the Good Lay Summary Practice guidance.234 Its recommendations are specific enough to use as acceptance criteria for a draft.
| Aspect | Recommendation |
|---|---|
| Literacy level | Aim for literacy proficiency level 2 to 3 on the international adult literacy scale. A well-written summary should be accessible to readers from about 12 years of age. |
| Readability tests | For English, the Flesch Reading Ease score (70 or above reads as easy) and the Flesch-Kincaid grade level, aiming at about 6th grade. The annex names equivalent tools for other EU languages. |
| Numbers | Give absolute numbers, with percentages; use whole numbers where possible, in the form "x out of y people (z%)". Avoid relative risks, odds ratios and confidence intervals, or explain them simply. Explain differences that were not statistically significant so they are not read as effects. |
| Words and sentences | Everyday words, short sentences, active voice. Define any technical term that is kept and use it consistently. Put a necessary medical term in brackets after its plain explanation. |
| Layout | Headings, subheadings, bullet points and white space; the overall picture before the detail. A 12-point font, black text on a white background, no text in capitals and no underlining. |
| Visuals | Simple, clearly labelled graphics with a caption and a short text explanation; they should still work in black and white. |
| Tone | Factual and non-promotional, in content and in formatting. Respectful terms for participants and patients. |
| Length | No fixed limit; as short as possible. Do not copy text from the technical summary. |
| Languages | At a minimum, the local language of each EU country where the trial took place, matching the languages of the participant information sheet. Translations must keep the meaning and the neutral tone. |
| Testing | Consider involving patients, patient representatives or members of the public in developing or reviewing the summary, and where feasible test readability with a small number of people from the target population. |
The recommendations also allow a child-focused version, particularly where a child-focused participant information sheet was used in the trial.2
Worked example: one results paragraph rewritten
Illustrative example with invented data
The product, trial and results below are fictional. The source paragraph is written in the style of a clinical study report efficacy conclusion; the rewrite covers Annex V elements 6 and 7.
Source text (CSR style)
In the full analysis set (N=412), the least-squares mean change from baseline in monthly migraine days over weeks 9 to 12 was minus 4.1 days with EV-550 140 mg once monthly (n=206) and minus 2.3 days with placebo (n=206), a treatment difference of minus 1.8 days (95% CI minus 2.5 to minus 1.1; p<0.001). The proportion of patients achieving at least a 50% reduction in monthly migraine days was 47.1% (97/206) versus 26.2% (54/206). Treatment-emergent adverse events were reported in 38.8% (80/206) and 34.0% (70/206) of patients, respectively; the most frequent adverse drug reactions with EV-550 were injection site reactions (6.8%) and constipation (3.4%). Serious adverse events occurred in 2 patients (1.0%) and 4 patients (1.9%); none was considered related to study treatment.
Lay rewrite
What were the results of the study?
412 people took part. Half of them (206 people) had an injection of EV-550 once a month. The other half (206 people) had an injection that looked the same but had no medicine in it (a placebo).
Before the study, people in both groups had migraine on about 8 days a month. The researchers counted migraine days again in the third month of treatment.
- People who had EV-550 had about 4 fewer migraine days a month than before.
- People who had placebo had about 2 fewer migraine days a month than before.
The researchers also counted how many people had their migraine days cut by half or more. This happened for 97 out of 206 people (47%) who had EV-550 and 54 out of 206 people (26%) who had placebo.
What side effects did people have?
A side effect is a medical problem that the study doctors thought could be caused by the treatment. The most common side effects of EV-550 were:
- redness, pain or swelling where the injection was given: 14 out of 206 people (7%)
- constipation: 7 out of 206 people (3%)
2 out of 206 people (1%) who had EV-550 and 4 out of 206 people (2%) who had placebo had a serious medical problem during the study. The study doctors did not think any of these were caused by the treatment.
What changed, and why
| Source wording | Lay wording | Reason |
|---|---|---|
| Full analysis set (N=412) | 412 people took part | Analysis-set terms are not needed when the number is the same; if it differed, say how many were counted and why. |
| Least-squares mean change of minus 4.1 and minus 2.3 days | About 4 and about 2 fewer migraine days a month | Whole numbers; direction stated in words. |
| Treatment difference, 95% CI and p-value | Omitted | The recommendations advise against confidence intervals unless explained; the two group results carry the comparison. |
| 47.1% (97/206) | 97 out of 206 people (47%) | Absolute number first, whole-number percentage. |
| Treatment-emergent adverse events 38.8% versus 34.0% | Omitted from this paragraph | Annex V element 6 asks for adverse reactions. All-cause event rates belong in the technical summary; including both invites confusion. |
| Adverse drug reactions | Side effects, defined in one sentence | Term explained at first use. |
| Baseline value (in a CSR table, not in the paragraph) | "About 8 days a month" added | A change means little to a lay reader without the starting point. |
Counts in the rewrite were derived from the source percentages (6.8% and 3.4% of 206 are 14 and 7 people). In a real summary, take counts from the safety tables, not from back-calculation.
Controls before submission
Trace every number
Each figure in the lay summary is matched to the technical results summary and to the report table behind it. Rounding is applied once, by rule.
Check the ten elements
Tick each Annex V element against a heading in the draft. Elements 8 and 9 are short and easy to leave thin.
Check neutrality
Remove adjectives about the product. State what was found in this trial and avoid claims about the medicine in general. GPP 2022 includes plain-language summaries among the company-sponsored publication types it covers.5
Measure readability
Run the tests named in the recommendations on the English text and record the scores. Revise sentences, not only words.
Reader review
Where feasible, have a small number of patients or members of the public read the draft and say back what they understood.
Translate and re-check
Translate from the approved English text and check that numbers, tone and meaning are unchanged in each language.
Plan the summary early. The one-year clock in Article 37(4) starts at the end of the trial, and the summary depends on final outputs that the report team is using at the same time. SPIRIT 2025 item 8 asks protocols to state plans for communicating results to participants and the public, including plain language summaries, so the commitment is often already in the protocol.6
Editverse Medical writes lay summaries from the report or final outputs, with the number trace and readability record delivered alongside; see medical communications: letters, lay summaries, slide decks. The source report itself is covered by the clinical study report (ICH E3) service, and related documents are listed under clinical study reports.
Frequently asked questions
Is a lay summary required if the trial failed or was stopped early?
Yes. Article 37(4) applies irrespective of the outcome of the trial. The summary explains what was planned, what happened and, for an early stop, why the trial ended.
Is there a word or page limit?
The Regulation sets none. The EU expert group recommendations say the summary should be as short as possible and note that plain explanations and translations tend to add length.
Can the lay summary be delayed with the technical summary?
The lay summary accompanies the summary of results. Where scientific reasons detailed in the protocol prevent submission within one year, the results summary is submitted as soon as it is available, and the protocol must say when and justify the delay.
Is the EU lay summary the same as a journal plain language summary?
No. The EU lay summary is a regulatory document with ten prescribed elements, submitted to the EU database. A journal plain language summary accompanies an article, follows the journal's format and goes through the journal's review. The same source data and the same plain-language principles apply to both.
References
- Regulation (EU) No 536/2014 of the European Parliament and of the Council of 16 April 2014 on clinical trials on medicinal products for human use, and repealing Directive 2001/20/EC. OJ L 158, 27.5.2014, p. 1. Article 37 and Annexes IV and V. EUR-Lex
- Expert group on clinical trials for the implementation of Regulation (EU) No 536/2014. Summaries of Clinical Trial Results for Laypersons. Version 2. February 2018. European Commission document (PDF)
- European Commission. EudraLex Volume 10: Clinical trials guidelines. Chapter V, additional documents. European Commission page
- Good Lay Summary Practice guidance. EudraLex Volume 10, Chapter V. European Commission document (PDF)
- DeTora LM, Toroser D, Sykes A, Vanderlinden C, Plunkett FJ, Lane T, et al. Good Publication Practice (GPP) Guidelines for Company-Sponsored Biomedical Research: 2022 Update. Ann Intern Med. 2022;175(9):1298-1304. PMID 36037471 · DOI
- Chan AW, Boutron I, Hopewell S, Moher D, Schulz KF, Collins GS, et al. SPIRIT 2025 statement: updated guideline for protocols of randomised trials. BMJ. 2025;389:e081477. PMID 40294953 · DOI