Clinical Trials

Reasons for wanting to take part in a clinical trial - personal benefit

People agreed to take part in clinical trials for a range of reasons. Some people were thinking mainly about their own personal health, while others were more concerned with helping other patients and medical research more generally. Often, people said their reasons for taking part were a mixture of these. Here we look mainly at how people hoped their own health would benefit. (See also ‘Reasons for wanting to take part in a clinical trial – helping medical science and other people’).

All those we interviewed either had a condition already or were healthy people in trials relevant to their own health, such as cancer screening or preventive care. We did not include ‘healthy volunteers’ who are usually paid compensation to take part in early trials of experimental treatments.

For many, the hope of personal health benefit was their main or only reason for taking part. This might include getting a new drug or treatment they thought might help them; learning more about their condition; being screened (hoping either to be reassured or to get an early diagnosis); the chance of getting access to care they felt would be better or more specialised; or faster access to care. Some people added that they took part for their own interest or curiosity.

Several people wanted access to a new drug or treatment that was only available at that time through a trial. These included people who had an immediately life-threatening condition such as cancer, some of whom believed it was their only hope, and others with a long term health condition or other health problems. 

In making their decisions, people weighed up potential benefits against possible risks or side effects. (See also ‘Side effects and queries about clinical trials’). But it is important to bear in mind that until a trial has been completed, no-one knows if a new treatment is better than the standard treatment already in use. ‘New’ does not necessarily mean ‘better’. Indeed, new treatments are as likely to be worse than existing treatments as they are to be better. The UK Clinical Research Collaboration booklet ‘Understanding clinical trials’ includes a useful section on the risks and benefits of trials (see Resources).

A few others also mentioned free prescriptions or payment of expenses, but usually as an additional rather than the main reason for taking part. (See also ‘Time commitment, money and other practical issues’).

Obtaining extra information was Sue’s main reason for taking part in a trial of various decision aids to help women with birth choices after a previous caesarean. (Our site on ‘Making decisions about birth after caesarean’ features interviews with other women involved in this trial).

Some evidence has suggested that people who take part in a trial – whatever treatment group they are allocated to - have better health outcomes than people who do not take part in trials. This is known as the ‘trial effect’. However,  in 2008 reviews of the evidence have shown no significant differences in health outcomes for people given similar treatments within a trial or just as part of their normal care. (See the Cochrane Review by Gunn Vist and colleagues - Outcomes of patients who participate in randomized controlled trials compared to similar patients receiving similar interventions who do not participate).

However, even if the outcomes are similar, many people felt they received better care in a trial than outside it, whether this meant more regular monitoring, more frequent appointments, being looked after by experts who specialised in their condition, or less rushed appointments and more time to ask questions.

Harry said he was usually reluctant to bother his doctor and saw the trial as an opportunity to be screened for problems before they became serious “I think I was 72, about, and I thought it would be a good time if I would have a medical procedure which would find out whether I had any age-related conditions which you would get but you wouldn’t know about it until it hit you hard…That was the main reason, of course naturally selfish - they’ll watch me and they’ll tell me if there’s anything wrong.”

People who take part in trials often feel they are taking an active part in their health.

Iain Chalmers,  one of the authors of the book 'Testing Treatments' (a web resource is available at,, commented “I carry around a card with me saying 'invite me to participate in any randomised controlled trial for which I am likely to be eligible'. I don’t do that out of any altruism; it's purely selfish.” 

Looking back, better care or attention was often mentioned as an unexpected benefit of taking part, even if it was not something that influenced the original decision to take part. Ronny said, “I think I possibly got the operation done quicker because I was in this clinical trial”, but other than that he thought there was no difference in treatment. Alex was originally told he might have to wait a week for a CT scan, but after consenting to the trial he had the scan within a couple of hours.

However, other people felt there was no difference in the care received. Wendy had thought being in a trial would mean better care but was a bit disappointed that this did not seem to be so. (See also ‘Appointments, monitoring and questionnaires’).

Meeting new people and building up friendly relationships with staff or other patients was also felt to be a plus looking back, but again was not a major reason for deciding to be in a trial in the first place.

(See also ‘Reasons for taking part in a clinical trial – helping medical science and other people’).

Last reviewed September 2018.
Last updated September 2018.


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