About Clinical Trials
What are clinical trials?
Clinical trials are research studies involving patients, which compare a new or different type of treatment with the best treatment currently available (if there is one). Some clinical trials also look at possible ways to prevent illnesses, for example by testing new vaccines. No matter how promising a new drug or treatment may appear during tests in a laboratory, it must go through clinical trials before its benefits and risks can really be known.
Trials aim to find out if treatments used in health care:
- Are safe
- Have side effects
- Work better than the treatment used currently
- Help people feel better
It is now widely agreed that a properly run clinical trial is the best way to assess whether a treatment is, or is not, safe and effective.
Why do we need trials?
Clinical trials are the most reliable and best way of testing a new treatment, or of seeing whether one treatment works better than another. A new treatment is not always better, and can sometimes be worse than existing treatments. Trials are therefore really important when we need to know whether one treatment is safer and more effective than another.
We need clinical trials to improve treatment and care for patients now and in the future.
Many of the treatments now commonly used in the NHS have been tested through clinical trials. For example, in Cancer care, trials have been used to try out new treatments – Radiotherapy, Chemotherapy, surgery, and complementary therapies. Trials have also been used to find out the best ways of using these treatments. This has meant that many people with cancer, HIV/AIDS and many other illnesses now live longer and have a better Quality of life.
Different types of trials
What is a randomised controlled trial?
Many clinical trials are randomised controlled trials (RCTs). Clinical trials aim to make a fair comparison between a new treatment and the current treatment on offer, or between two (or more) existing treatments, to see which one works best.
A controlled trial compares two groups of people: an experimental group who receive the new treatment and a control group, who receive the usual treatment or a placebo, if there is no ‘usual treatment. The control group allows the researchers to see whether the treatment they are testing is any more or less effective than the usual or standard treatment.
If you take part in a randomised controlled trial, you will usually have an equal chance of receiving any of the treatments being compared. The decision about which treatment you’ll receive is random – based on chance. A computer programme will ‘decide’ which treatment you’ll receive, not you or the doctor. This is called randomisation.
Randomisation ensures that the two groups of people in a trial are as similar as possible, except for the treatment they receive. This is important because it means that researchers can be sure that any differences in outcomes between the groups are therefore only due to the treatment.
Randomisation is also the best way of ensuring that the results of trials are not biased. For example, if a doctor chose which treatment a patient should receive as part of a trial, she or he might give the new treatment to sicker patients, or to younger patients. This would make the results of a trial unreliable. Randomisation helps prevent this kind of bias.
Across the world, randomised controlled trials are now seen as the most reliable way to test new treatments and to compare two (or more) existing treatments, to see which one works best.
To find out about clinical trials currently recruting in the UK and Europe please click on the links below:
This information is reproduced with the kind permission of the Medical Research Council’s clinical trials unit.
This page was last modified on 23rd January 2011 at 09:11