Clinical Trials

Information and questions about clinical trials

A doctor, nurse or other researcher should always seek your consent to enter you into a clinical trial. They cannot enter you into a trial if you do not give your consent. It is important that you have enough information to give informed consent, and an opportunity to ask as many questions as you like. The UK Clinical Research Collaboration booklet on ‘Understanding Clinical Trials’ (see Resources), has a checklist of questions you might like to ask. You can print off the pages which include space to jot down your own notes.

People have different preferences for how much information they want. To help you decide whether to take part, the researcher should explain:

• The aim of the study – which uncertainties it is addressing and what it is trying to find out
• How you will be treated and what you will need to do
• What the possible risks and benefits are

You will also be given an information leaflet or ‘patient information sheet’ which you can take away and read. If you decide to take part, you will be asked to sign a consent form to say you agree to take part. (If English is not your first language, the trial should be explained to you in your preferred language and you should be given a consent form in that language).

Many people we talked to felt they had been given very good, clear explanations and were able to make informed choices. Here, Sue explains how she was given both face-to-face and written information, an account of what the trial was testing, reassurance that she could withdraw at any point and a guarantee of confidentiality.

Sue could not remember much detail about the specific interventions, some months after the trial. This may be partly because, for many people, the trial does not feature as strongly in their memories as their illness or condition, even if at the time they had all the right information. As Angela said, “I felt informed. I may have forgotten since.”

In some cases, it may also be partly because it can be difficult to take it all in at the time. Wendy mentioned that she was given a tape recording of the consultation with the professor in which they discussed the trial so she could listen to it again at home. She thought this was a good idea. Others said it helped to have another family member or friend there with them to help remember what was said. In one trial, people were given a useful DVD to watch as well as written leaflets. Seeing as well as reading made it easier to grasp.

As far as Alex was concerned, the trial was not something he felt needed much discussion with other people. However, others valued having time to discuss it with family, friends (including friends working in healthcare) or another health professional. (See also ‘Being asked about taking part in a trial’).

As Julian and Tom pointed out, each person will want different levels of information and it is very hard for professionals to get this right each time. It is also difficult for patients to know what to ask.

Everyone in a particular trial will be given the same patient information sheet, which will have been approved by a Research Ethics Committee, and which has to contain certain standard information. Some people found the information sheet just right, but some thought it was too complicated, while others thought it was not detailed enough.

Marie was put off the trial because she felt some key facts might be being withheld from her, or at least not made obvious. Like Marie, Rosamund felt some key things were missing from the information leaflet that should have been included. These included the fact that there might be some discomfort involved in having one of the interventions (a vaginal ultrasound scan for ovarian cancer screening), and the possibility that screening tests might produce false positive or false negative results. (A false positive would mean an incorrect diagnosis of cancer, while a false negative would reassure a woman that she did not have cancer when in fact she did, but the test had not picked it up).

Leslie was also concerned that some important things were missing from the leaflet.

Some people commented that they did not really read the information leaflet fully. As Judith said, “I’m still not one for reading through great booklets of it.” Not everyone wants or is able to read a long leaflet, especially if English is not their first language. Rose thought that, although she personally was happy to read things, more face-to-face discussion would help many people, but busy staff might not always have time to do this.

Some people we talked to did not want to know much about the trial they were involved in. It was clear, for example, that a few were not really aware that the trial was comparing different treatments or that people were allocated at random to one group or another. (See also ‘Feelings about being allocated (randomised) to a treatment group’). Several people said that they preferred to trust their doctor to give them the explanations they needed, or that they had no option but to do so, given that they could never have the same level of medical knowledge. Some were happy with this situation, while others were troubled by the unequal relationship. There is considerable debate about how much information is ‘enough information’ to be sure consent can be properly informed.

Lester suggested that having lay people involved in writing trial leaflets in the first place was a good way to make them more understandable. (See also ‘Public awareness and involvement’).

Several people who did try very hard to understand the leaflets found the amount of information rather overwhelming, and found the more questions they asked the more confusing it became. As Hazel commented, “The more I was finding out, the more I realised I couldn’t possibly give informed consent.”

A key problem is that randomised trials are done when we don’t know which treatment is best, in other words when the relative merits and disadvantages of different treatments are uncertain. So researchers need to explain this uncertainty to people. But uncertainty can feel very uncomfortable for patients and make it hard for them to feel they have enough firm information to make a decision. Joanna described a debate with a doctor over her husband’s leukaemia trial. Carers may have their own rather different information needs. “I got very uppity about, ‘What is informed consent? If you can’t give the information I need, how can one make informed consent?’”

At a time when people are already feeling vulnerable following a diagnosis or a hospital admission, dealing with information about uncertainty and difficult choices can seem too much. (See also ‘Being asked about taking part in a trial’). Sometimes people may want to choose not to have a lot of information and to trust their doctor to advise them. Polly (below) comments that ‘choice and trust are in different boxes’.

Some people did not remember being given any information about uncertainty and some people, particularly in drug trials, felt it was being suggested that the drug being tested would bring them extra benefit. Of course trials are done because there is a possibility that a new treatment will be better than the standard or control treatment, and it may have already been shown to work for other conditions or groups of patients.

However, trials are just as likely to find that new treatments are no better, or indeed worse. Patients who desperately want to get better may interpret doctors’ words in a way doctors do not mean, or “read between the lines”, as Wendy said. This underlines the importance of staff being very careful about what they say and how. (See also ‘Being asked about taking part in a trial’, ‘Feelings about being allocated (randomised) to a treatment group and ‘Messages to professionals’).

Many people pointed out how difficult it is to absorb information or remember accurately what they were told, however hard staff may try to help them understand. Again, having someone else there with you can help. Caroline commented that in pregnancy, “Your brains do turn to mush a little bit….I would have found it quite difficult to concentrate probably.” At first Judith was just keen to get treatment started for her lymphoma, but now questions have started to occur to her.

The process of informed consent should continue throughout the trial. The researchers should continue to give you information and answer your questions. They should let you know if any new relevant information about treatments comes up during the trial so that you can re-think your decision, and withdraw if you want to.

Last reviewed September 2018.


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