Clinical trials: Parents’ experiences

Deciding not to enrol your child and when your child may not be eligible

Everyone who is invited to take part in a trial is free to decline, and should not feel under any pressure to take part. You are also free to leave a trial at any time and without giving a reason; see ‘Withdrawing your child from a trial.’ Reasons for deciding not to enrol a child in a trial varies from parent to parent.
Ruth had considered enrolling her son in a swine flu vaccine trial partly because she thought it might help protect her husband, who was in the ‘at risk’ category because he has asthma. She also wanted to protect her parents as they often helped to take care of her son. After reading the information and talking to her husband and work colleagues, Ruth began to doubt her initial reasons. She became worried about the possible risk of side effects for her son. It was important for her that it was a joint decision with her husband. There was plenty of time to make the decision and finally she decided to decline. However, Ruth is supportive of clinical trials and would certainly consider something similar in the future.
Other parents who decided not to enrol their children in trials also said they were still very supportive of medical research in general and would consider enrolling their children in trials in the future. The decision not to take part felt right for them and their children at the time.
Shortly after her son was discharged from a neonatal unit, Catherine received an invitation to consent for him to take part in a five-in-one vaccine trial. On this occasion she declined. She had recently taken part in a trial during her stay on the neonatal unit and her son was having further treatment for two hernias. It was the wrong time for her and her son.
In vaccine trials, parents are generally weighing up the risks and benefits of exposing an otherwise healthy child to something which has not yet been fully tested.

There is no scientific evidence of a link between MMR and autism, but this is something that parents still worry about. For further information see our section on Immunisation.

In other cases, parents are making a decision about a child who is already ill. Many trials compare a new treatment with the current standard treatment by setting up two groups of people. One group of people will receive the new treatment and one group will receive the current standard treatment. If no standard treatment exists a placebo will be given. A placebo is a treatment with no active ingredient which is designed to appear very like the treatment being tested. By comparing people’s responses to the standard or the placebo treatment with the new treatment, researchers can tell whether the treatment is having any real benefit, rather than simply feeling better because ‘something is being done’.
(Sometimes you may hear the new treatment group called the ‘experimental group’, ‘trial group’ or ‘intervention group’. This can be confusing, as all the groups, including the control group, are part of the trial, and people in the control group may also be given an intervention, in the form of the standard treatment or placebo.)
A trial may involve invasive procedures and tests, and parents and children may worry about this. Nikki’s daughter did not want to take part in a research study in children with asthma because it involved a cannula insertion (a fine tube put into a blood vessel) to take blood for testing. They decided not to take part in the trial this time.
Both Lucinda and Nikki agreed to enrol their children in trials when given a second opportunity. Their experiences show that even if you decide not to enrol your child in a trial there may be other opportunities for the same or other trials in the future.
Helena is a senior research nurse. She says that part of her role is to ensure that parents understand they can decline and that this decision will not affect any future opportunities to participate in research, or that their children will receive the best known care.
All trials have a set of guidelines about who can take part. These guidelines are called eligibility criteria. They ensure that a trial includes the people considered likely to benefit from the treatments and to protect participants from avoidable risks. The inclusion criteria help researchers decide who can take part in a trial, and the exclusion criteria indicates who cannot take part. Sometimes children will be tested to see if they are eligible and to ensure that they are unlikely to be harmed by treatment.
Alison’s first experience of being invited to enrol her baby in a trial was during her stay in a neonatal unit. At the time, she and her baby were very poorly. Her baby’s growth had stopped in pregnancy, so it was likely the baby would need to be put on a ventilator after birth. The trial was a randomised trial to determine the most effective type of ventilating machine. So Alison and her husband agreed to take part as it all seemed straightforward. 
For Alison the fact that her son was no longer eligible for the trial was good news, but sometimes not being eligible can be disappointing. Julie’s baby was not eligible to take part in a study of babies and young children developing food intolerance. Julie was keen for her baby to take part and was disappointed when she was told he did not meet the inclusion criteria. Julie herself takes part in clinical trials as a healthy volunteer. She believes it is important it is to take part to advance medical knowledge and improve the health of children and adults.
Catherine had experienced recurrent miscarriages and was invited to join a trial of a hormone (progesterone) before her son was born. However. The eligibility criteria meant she could not take part.
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Last reviewed September 2018.
Last updated 
July 2015.



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