Frequently asked questions about taking part

By attending all your appointments, you will be helping research to understand how the NHS might be able to offer the Galleri blood test to people in the future. The blood sample you provide at each appointment will form an important part of the research.

One of the questions researchers want to answer is how often people should be tested with the Galleri test to help the NHS find cancer early. Looking at your blood samples spaced about 12 months apart will help researchers to answer this question.

Testing blood samples after the second and third appointments may find more cancers at an early stage. 

However, you do not have to attend your appointments if you do not want to. If you decide not to attend, you do not have to give a reason why and your normal medical treatment will not be affected.

One of the questions researchers want to answer is how often people should be tested with the Galleri test to help the NHS find cancer early. Looking at your blood samples spaced about 12 months apart will help researchers to answer this question.

Testing blood samples after the second and third appointments may find more cancers at an early stage.

You will be sent a letter when it is time to book your appointment. This will be about 12 months after your previous appointment. If your letter doesn’t arrive, please contact the trial team.

If you would like to cancel your appointment and not rebook, please call freephone 0800 030 9245. Phone lines are open from 8am to 7pm, Monday to Friday (excluding bank holidays). You will need to have your NHS number, date of birth and contact details ready. You can also use this phone number
to change your appointment.

If you have moved house, please update your contact details using the link below. You will be sent a letter when it is time to book your 24 month appointment.

If you still live in England but are not registered with a GP in one of the areas where the trial is taking place, you can still take part but may need to travel further to attend your next appointment.

If you have moved out of England, you will be unable to attend your next appointment. This is because the trial is run in partnership with NHS England only. However, information that has already been collected will be used and will continue to help research. Please contact the trial team for more information.

Your NHS number is a 10 digit number, like 485 777 3456. It is on any letter you receive from the NHS.

If you do not know your NHS number you can use the following service to get it.

The NHS-Galleri trial is not accepting new participants at this time- registration is closed. Participants who have already registered will be sent a letter when it is time to book their next appointment.

You can ask for the collection of information about your health from the NHS to stop at any time, and you do not have to give a reason why. However, information about you that has already been collected will be kept. 

If you would like to stop this data collection, or if you want to leave the trial, please contact the trial team.

You can change your mind about your samples being stored for future research, and you do not have to give a reason why. If you do not want your samples to be stored for future research, please contact the trial team. Your stored samples will then be destroyed.

You do not need to contact the trial team if you move house or leave England after your last trial appointment.

Once information has been collected from all the trial participants, it will be analysed to see if using the Galleri test alongside existing cancer screening can help the NHS to find cancer early. 

The final results of the trial will be checked by other researchers to make sure the results make sense. This is how high-quality research is done – it always needs to be checked by other researchers. 

Once the results of the trial are available, these will be shared publicly. Often this is in a science journal, press release, or on the trial website. Results are likely to be ready in 2026 but may take longer.

A trial is a type of research study that aims to understand whether a new treatment or test works better than other approaches that are already being used. 

If you take part in the trial you will need to give a number of blood samples. Giving blood samples is generally safe but there are some possible side effects including:

• discomfort
• lightheadedness
• infection

If the test detects a cancer signal, you could experience anxiety or distress. Like all screening tests, the Galleri test is not perfect and can give a wrong result. If the test detects a cancer signal and no cancer is found by the doctor, you may have had further tests that were unnecessary. Those further tests can have their own risks, such as radiation from scans, that you should discuss with your doctor before having them.

The trial team will try to make sure people who take part in the NHS-Galleri trial have a good trial experience. 

The trial is taking place in the following eight Cancer Alliance areas in England:

• Cheshire and Merseyside
• East of England (North)
• Greater Manchester
• Kent and Medway
• East Midlands
• West Midlands
• Northern
• South East London

During and after the trial, the test and control groups will be compared. One of the results that will be looked at is if cancers are found at an earlier stage in the test group than in the control group.

Additional information will be recorded about diagnostic tests and cancer treatments given.

People in the control group will have their blood samples stored. These samples may be tested with the Galleri test in the future. If you are in the control group, you will not get any test results if your samples are tested in the future, not even after the trial is finished.

About half the people who have a cancer signal detected will be found to have cancer after further tests in the NHS, and the other half will not.

If the Galleri test finds a cancer signal, but no cancer is found after further tests, please continue to attend any cancer screening appointments you are invited to and visit your GP if you experience any symptoms that are new or unusual for you.

If you are in the control group, or if no cancer signal is found, you will be sent a thank you letter to confirm that your blood sample has been safely received by the lab. This normally takes around 30 days to arrive after you have had your blood sample taken, but may sometimes take longer. 

You will not know from the letter if your blood sample has been tested or not. It is therefore important that you continue to attend any cancer screening appointments you are invited to and visit your GP if you experience any symptoms that are new or unusual for you.

The control group samples may be tested with the Galleri test in the future to help the trial team understand any differences between what happens to people in the test group and the control group. If you are in the control group, you will not get any test results from the trial, not even after the trial is finished. You will be asked if your samples can be stored and tested after the trial ends to help with other research to improve how well the test works.

You will be asked to give permission for the trial team to share and receive health information about you with the health professionals who are involved in your care. This could include your GP. If the Galleri test finds a cancer signal in your blood, your GP will be told about this. 

If you have or are planning to purchase private health insurance, life insurance, or travel insurance, you should check with your provider if taking part in this trial will affect your ability to make claims in the future.

If you are found to have cancer by taking part in the study, you may have to provide this information on an insurance application if you are asked for it.

The Galleri test is not currently available on the NHS or to buy in the UK. The test is only available in England as part of clinical trials.