What are “randomised” trials?


Most clinical trials are randomised trials. If you take part in a randomised trial, a computer, not a doctor, will decide which treatment to give you. This decision will be random. It will be due to chance alone, and not based on your doctor's decision. Randomisation is the best way of ensuring that people in the different parts of a trial are broadly similar. By comparing similar groups of people, investigators can be sure that their trial is checking the difference between the treatments being studied, and not the differences between the people taking part. Randomisation is important because investigators need to ensure that clinical trials are not biased. It is quite easy for people to be biased without realising it.