Clinical trials are usually discussed in terms of testing new medicines and advancing medical research. There is less discussion of what happens to participants during the screening process itself, often before any treatment is given at all.
In this episode of the My Health Focus podcast, we explore what years of trial screening data can tell us, and why it has led two researchers to question one of the most familiar lines in trial paperwork.
Joining us are Kate Dodd, Recruitment and Engagement Manager at the NIHR Liverpool Clinical Research Facility, and Lauren Walker, the Facility’s Deputy Director. Together we discuss what their research uncovered, the real diagnoses it has led to, and why they believe trial paperwork needs to say more about what screening can actually involve.
Top 5 highlights from the conversation
1. Trial screening is far more thorough than most people expect
Before anyone takes part in a trial, they go through a screening appointment, and it covers far more than simply confirming eligibility. Kate describes it as a kind of full health MOT, checking the heart, liver, kidneys and blood pressure among other things. For people without the condition being studied, often called healthy volunteers, this can be the most complete health check they have had in years, particularly for anyone who finds it difficult to get a routine check-up through their GP.
2. That screening sometimes finds things nobody knew about
Across the eight years of data Kate and Lauren reviewed, a clinically significant abnormality was identified in around one in 17 healthy volunteers and one in 25 patients. The conversation returns to three real examples behind those numbers. One participant was found to have hepatitis B and latent TB during screening for a respiratory trial, and was treated for both. Another, screening for a COVID vaccine trial, had blood results that led to a diagnosis of lymphoma. A third had a routine ECG that led to a diagnosis of Wolff-Parkinson-White syndrome, a heart rhythm condition. None of these participants went looking for a diagnosis. Screening found it for them, and in each case, led to treatment that might otherwise have come much later.
3. Most of what gets found is silent until somebody looks
Kate and Lauren are clear that the more common findings are quieter than these three cases, mainly issues with blood pressure and cholesterol. These conditions tend not to cause symptoms for years, which is exactly why they go undetected. As Lauren puts it, you do not feel high blood pressure or high cholesterol, you only find out you have them if somebody deliberately checks, and the earlier that happens, the more time there is to do something about it before it becomes something more serious.
4. This raises a genuine question about what trial paperwork should say
If screening regularly turns up real, actionable health information, is it honest to tell people there is no benefit to taking part? Kate and Lauren are careful not to overstate their case. The goal is not to suggest a benefit that might tempt someone into a trial against their better judgement, but to be properly upfront about what participation can actually involve, including the chance that something gets picked up along the way.
5. They want it written down properly, in language people can understand
Kate and Lauren are now working with the relevant authorities to change how this is explained in trial paperwork. Community engagement work tested proposed wording with members of the public, who found the original version too complex to follow easily, and helped shape a simpler, clearer version in its place. That work is ongoing.
Final Thoughts
What Kate and Lauren’s work shows is that the line so many participants are asked to accept without question, that taking part in an early trial offers them nothing directly, is not always true.
About the expert
Kate Dodd is the Recruitment & Engagement Manager at the National Institute for Health Research (NIHR) Clinical Research Facility: Liverpool, and a PhD student at The University of Liverpool. Kate has a passion for Patient Public Involvement and Engagement, and ensuring that research is inclusive, acceptable and available to all communities. This passion forms the basis of her PhD which is looking at inclusivity in early phase clinical trials.
Medical disclaimer
This content is for general information only and is not a substitute for professional medical advice. Always consult your GP or a qualified healthcare professional if you have any concerns about your health.
Further Reading:
The Hidden Benefits of Clinical Trials