How clinical trial results are used

This page tells you about the results of clinical trials and what happens when a treatment is proven to work. There is information about

What happens to your results

Your doctor, or a researcher, enters your test and check up results onto a form. After all the information has been collected, it is given to a team of statisticians. The statisticians use a computer to analyse the results of all the people taking part. Then the researchers produce a report about how well the treatment worked. And how many patients had side effects. We have more information about what trial results mean.

The trial reports never have any patients names or other details that could identify you. They are all confidential.

We have more about how information about you is collected.

Publicising the trial results

Medical researchers have a responsibility to publish their results. After all, patients are giving up their time and energy to take part. It is important that the results become widely known so that cancer treatment can improve.

Results are usually published in medical journals (magazines). Sometimes the results are also presented at meetings and conferences attended by doctors and nurses involved in cancer research and cancer care.

We have more information about where and when trial results are published.

We include plain English summaries of trial results on our clinical trials database, and are adding more each month. You can select 'have results available' from the drop down list on the trials search to see them.  We also cover the results of large and important trials on our research pages for specific types of cancer.


Results for several trials of the same treatment may be analysed together and published. This is called a meta-analysis.

How a new treatment is adopted - licensing

If a series of trials shows a new treatment to be better, it will become the standard treatment. This can happen in a number of ways

  • The Royal Colleges may issue new clinical guidelines for doctors
  • The NHS Centre for Reviews and Dissemination of research may produce a report on treatment options for a particular disease
  • The National Institute for Health and Care Excellence (NICE) may issue treatment guidelines for the NHS in England and Wales
  • The All Wales Medicines Strategy Group (AWMSG) may issue drug treatment guidelines for the NHS in Wales
  • The Scottish Medicines Consortium (SMC) may issue treatment guidelines for the NHS in Scotland
  • The Department of Health, Social Services and Public Safety (HPSS) may issue treatment guidelines in Northern Ireland
  • The Department of Health (DH) may issue a statement as guidance for doctors

If the treatment is a new drug, or a drug is being used for a different condition, it must be licensed before doctors can prescribe it. This is either done by the Medicine and Healthcare Products Regulatory Agency (MHRA) or, more often, by the European Medicines Agency (EMA). We have more information about drug licensing in the UK and Europe.

Once a drug is licensed, in theory doctors are able to prescribe it. But it is often some time before it is widely available on the NHS. Sometimes health bodies won’t fund a new drug because they don’t think the benefit justifies the expense.

Getting access to new treatments on the NHS

'Post code prescribing' was a big issue in the UK a few years ago. Decisions about whether to provide expensive treatments were taken locally – by regional or district health authorities. So, if you lived in one part of the country you could get a particular drug. But in another, you could not.

Understandably, this upset a great many patients and doctors. It was very unfair. So an organisation called the National Institute for Health and Care Excellence (NICE) was set up. There is also the Scottish Medicines Consortium (SMC) in Scotland, the Department of Health, Social Services and Public Safety (HPSS) in Northern Ireland and the All Wales Medicine Strategy Group (AWMSG) in Wales.

The role of NICE, the SMC, the HPSS and the AWMSG is to look at the results of clinical trials and decide

  • If there is enough evidence from trials that a new treatment is better than existing treatments
  • If the benefits of the new treatment outweigh the increased cost of using it

If so, they can recommend that the treatment should be available on the NHS. They take all aspects of using a new treatment into account. For example, a new treatment may have fewer side effects than the standard treatment being used. Or it may be possible to have it as an outpatient instead of being in hospital. So the overall cost will be less. They weigh up all the evidence and consult experts in relevant fields. Once they have reached a decision, they publish the results in full and also as a shorter leaflet for patients and the public.

NICE can take some time to review all the evidence and come to their decision. So there is sometimes still a difference in the availability of expensive drugs around the country for a while. One issue is that the SMC may sometimes make a decision about a particular treatment more quickly than NICE. So there are occasions when a treatment has been approved in Scotland but not in England or Wales. Sometimes new treatments are not approved for use on the NHS. If doctors or researchers do not agree with these decisions, they can appeal.

Some drugs haven't been approved by NICE. This could be because NICE haven't looked at them, or NICE have said they don't work well enough or are not cost effective.

The government has set aside money for people who live in England to pay for cancer drugs that haven't been approved by NICE and aren't available within the NHS in England.  This is called the Cancer Drug Fund.

We have more information about

Last reviewed

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

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