Clinical trials & medical research

Being invited to take part in a clinical trial: information and questions

Most young people we talked to were invited to take part in trials at their regular clinic appointments, or when they were staying in hospital.

Some of the young people we talked to heard about clinical trials through other means, such as adverts in journals, or by a letter from their GP, or school. Some heard about trials by email, and actively pursued taking part themselves rather than waiting to be asked. 

A doctor, nurse, or other researcher should always give you information about what is involved, to help you decide whether to take part in a clinical trial. If you are aged 16 years and older you cannot enter a trial unless you have given your consent and signed a form to say you agree to take part. If you are under 16 years of age, you cannot give formal legal consent, this has to be given by a parent or guardian, but you should be involved in the decision as far as possible. In this case, you may be given an ‘assent’ form to sign. Assent means children give their permission or agreement to take part in trials. (See below for a fuller explanation of what assent means.)

It is important that you have enough information to give informed consent, or assent, and an opportunity to ask as many questions as you like.

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You should also be given time to make a decision. (See also ‘Making the decision to take part and giving assent and consent’.) The UK Clinical Research Collaboration booklet on ‘Understanding Clinical Trials’ has a checklist of questions you might like to ask. You can print off the pages, which include spaces to jot down your own notes. 

To help you decide whether to take part or not, the researcher should explain'

The aim of the study – 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, or your parents/guardians will sign a consent form and you will sign an assent form.

Most young people we talked to felt they had been given very good, clear explanations and were able to make informed choices. They, or their parents, received written information and the doctors and nurses explained the purpose of the trial and what it involved. All the young people we talked to were reassured that they could withdraw from the trial at any time without affecting their care.

Kay was invited to take part in a randomised placebo controlled trial to test a new drug for cystic fibrosis and neither Kay nor the doctors and those treating her would know which drug she would be taking. She was impressed by how detailed the information was, including all possible known side effects and what to do if she experienced any. 

The doctors and nurses were always very helpful and supportive and this was very reassuring for young people. Many of the young people we talked to said how much they valued being able to talk face-to-face to a member of the research team and ask as many questions as they liked, as some of the written information can be quite complicated (see below). This helped them build trust with the staff. 

Some of the young people we interviewed were invited to take part in trials soon after they were diagnosed. Being invited to take part in a trial at this time was overwhelming for some young people. 

In fact, many young people we spoke to said they would like information to be shorter, easier to read with simpler explanations, especially when there are complicated terms and procedures, and the use of pictures when appropriate. 

Ryan, aged 12, is taking part in a randomised placebo controlled drug trial. This is the first clinical trial he has taken part in. He says that the information he received was too difficult for him to understand because it used too many long words and he was too shy to ask questions. 

It is important that trial information tells you what you want to know about the study. It may contain a lot of medical terms. Alexander, aged 18, was invited to take part in a randomised placebo controlled trial to test a new drug for arthritis. The information he was given contained a lot of medical jargon that was difficult to understand.  

When Stephanie was invited to take part in a trial there was little known about the trial drug in the treatment of Wegener’s granulomatosis, a rare condition in young people. She had lots of questions about side effects and also searched the internet.

Some of the younger people we interviewed felt that they should receive the information before, or, at the same time as their parents.

Some of the young people we interviewed said they didn’t have any questions about the trial because they felt that everything had been explained to them and they couldn’t remember much about the information or what questions they had asked because it was quite a long time ago that they took part. However, like Stephanie above, possible side effects on fertility was an issue for a number of young people taking part in drug trials. 

A few young people said they might have liked to understand more about the trial, but at the time it wasn’t the most important thing they were worrying about. 

In addition to having written information about the trial some young people had a video to watch. Jenna, aged 13, was invited to take part in a randomised placebo controlled trial. She was pleased to have her own written information and a video that explained about the trial. Researchers may want to consider using a video or other similar technology. (See ‘Young people’s messages to health professionals’.)

Explaining assent

Assent means children give their permission or agreement to take part in trials. To give assent children need to understand the research process and be informed about what they are expected to do. All children have the right to receive information given to them in a way that they can understand, and to consider assenting, or not (to say they agree to take part, or not). In deciding whether to give assent, children can express their views and any worries about taking part. Doctors need to listen to the opinions and wishes of children who are unable to give full consent, and do their best to help them. Consent from parents and assent from children are both needed for children under the age of 16 to take part in clinical trials. 

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.) 

Last reviewed March 2017.


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