Clinical Trials Plain & Lay Language Summaries 

Published 10th February 2023

Clinical Trials Plain and Lay Language Summaries

The use of the clinical trial information system (CTIS) is now mandatory for all initial clinical trial applications in the European Union (EU), as of the 31st January 2023. 

With this and the EU CTR, plain and lay language summaries are introduced at the start and the end of a clinical trial. 


Plain Language Protocol Summary (EU CTR Annex I, D24) 

A plain language protocol synopsis helps any stakeholder understand why and how the trial will be done, without the intricate details of the full protocol.  

The EU CTR Q&A document, Question 5.8 lists the respective requirements for a  2 page document and asks sponsors to consider making the synopsis understandable to a layperson. The plain language protocol summary can be part of the protocol, or a separate document submitted with the protocol. National language requirements apply. A total of 9 elements are required: 

  1. 1. EU trial number and full trial title 
  2. 2. Rationale 
  3. 3. Objective 
  4. 4. Main trial endpoints 
  5. 5. Secondary trial endpoints 
  6. 6. Trial design 
  7. 7. Trail population 
  8. 8. Interventions 
  9. 9. Ethical considerations, in particular the expected benefits and the nature and extend of burden and risks  


In practical terms, a plain language protocol summary, coordinated with the patient information sheet-informed consent form, may also aid the consent process.  

For submission in the United Kingdom, the ISRCTN registry (Health Research Authority [HRA]-ISRCTN registry partnership) requires a ≤ 1000 word, plain English summary of the research, which will be made publicly available. Requirements are similar to the above, but also include several United Kingdom specific elements (eg, site, funding, and contact details) 


Lay Summary of Clinical Trial Results 

This lay summary helps the public, including trial participants, understand the results of a trial. Lay summaries will be publicly available. The EU CTR  (39) specifies the requirement for a lay summary of clinical trial results. The EU CTR Q&A document, Section 6 provides further details and Annex V of the EU CTR lists the required 10 elements:

  1. 1. Clinical trial identification
  2. 2. Name and contact details of the sponsor
  3. 3. General information about the clinical trial
  4. 4. Population of subjects
  5. 5. Investigational medicinal products used
  6. 6. Description of adverse reactions and their frequency
  7. 7. Overall results of the clinical trial
  8. 8. Comments on the outcome of the clinical trial
  9. 9. Indication if follow up clinical trials are foreseen
  10. 10. Indication where additional information could be found


In the United Kingdom, the HRA ask sponsors to include a plain language summary of their findings with the clinical study report (CSR). Requirements are very similar to the above. 

The extended use of plain and lay language summaries creates new and exiting opportunities for sponsors to interact with the public, patients, and potential trial participants.  

DLRC Medical Writers and Regulatory Professionals can help you assess the impact of these requirements on your clinical trial(s), provide advice on appropriate strategy (in conjunction with other results publishing requirements), and author or review plain and lay language summaries for you.  For our support, get in touch with our experts using the link below.