Clinical trials and research - What are clinical trials?
- Introduction
- Types of research
- How research addresses what we don't know
- What are clinical trials?
- Different stages of trials
- About fair tests
- Getting involved in health research
- Joining a clinical trial
- Finding out about the results
- Why all research should be registered
- Systematic reviews and meta-analyses
- How trials are regulated
- Ethics committees
- Data monitoring committees
- When things go wrong
- Sheilas-story
- 'The nurse made sure I understood the risks'
- 'I'm here because of women who took part in research'
- 'I thought it might help me or someone else'
- 'I want people to find better medicines'
- 'I can control my Parkinson's thanks to animal research'
- 'I'm lucky I found a trial that was so right for me'
A clinical trial is a type of clinical research that compares one treatment with another. It may involve patients or healthy people, or both.
Small studies produce less reliable results than large ones, so studies often have to be carried out on a large number of people before the results are considered sufficiently reliable.
Why clinical trials are important
Doctors and other healthcare professionals and patients need evidence from clinical trials to know which treatments work best. Without this evidence, there's a risk that people could be given treatments that have no advantage, waste NHS resources, and might even be harmful.
Clinical trials help to find out if:
- treatments are safe
- treatments have any side effects
- new treatments are better than the standard available treatments
Many NHS treatments have been tested in clinical trials. But the evidence for some treatments is incomplete. Read more about what we don't know.
The NHS aims to inform patients about research relevant to them and offer more patients the opportunity to take part in clinical trials if they want to.
What clinical trials can find out
Clinical trials can help:
- prevent illnesses by testing a vaccine
- detect or diagnose illnesses by testing a scan or blood test
- treat illnesses by testing new or existing medicines
- find out how best to provide psychological support
- find out how people can control their symptoms or improve their quality of life – for example, by testing how a particular diet affects a condition
Trials follow a set of rules, known as a protocol, to ensure they're well designed and as safe as possible, they measure the right things in the right way, and the results are meaningful. A full protocol should be available to anyone who's considering taking part in a trial and wants to see it.
Many clinical trials are designed to show whether new medicines work as expected. These results are sent to the Medicines and Healthcare Products Regulatory Agency (MHRA). The MHRA then decides whether to allow the company making the medicine to market it for a particular use.
Read more about safety and regulation.
Entering a trial
If you're receiving treatment for a medical condition, you may be asked if you would like to be part of a trial. You might be interested in finding out about trials taking place so you can volunteer to join one.
Read more about taking part in clinical trials, including how to join a trial.
© Crown Copyright 2009
