The ASCEND2 study was a follow-on study to the ASCEND research project and involved 370,000 people within the NHS Bowel Cancer Screening Programme in England. The project involved a collaboration between the NHS Bowel Cancer Screening Programme, University College London, Queen Mary University of London and the CSPRG (Imperial College London). The study was funded by Cancer Research UK.


The trial is registered with the ISRCTN registry. Its unique number is 11660314.

Our Data Protection and Privacy Notice

Imperial College London is the sponsor for the studies run by the Cancer Screening and Prevention Research Group (CSPRG). We will be using special category, personal information from health care records, either directly from NHS Trusts or via third parties such as NHS Digital, the Office for National Statistics, National cancer registries, including the Welsh Cancer Intelligence and Surveillance Unit, and Information Services Division (Scotland), in order to undertake these studies where we will act as the data controller. This means that we are responsible for looking after your information and using it properly. CSPRG / Imperial College London will keep special category, personal data about you for 10 years after the study has finished.

As a University we use personal data and special categories of personal data to conduct research to improve health, care and services. As a publicly-funded organisation, we have to ensure that it is in the public interest when we use personal data and special categories of personal data from people who have agreed to take part in research or where we have section 251 approval to obtain, process and hold such data.

Your rights to access, change or move your information are limited, as we need to manage your information in specific ways in order for the research to be reliable and accurate. If you withdraw from the study, we will keep the information about you that we have already obtained. To safeguard your rights, we will use the minimum personally-identifiable information possible.

Health and care research should be in the public interest, which means that we have to demonstrate that our research serves the interests of society as a whole. We do this by following the UK Policy Framework for Health and Social Care Research.

When you agree to take part in a research study, the information about your health and care may be provided to researchers running other research studies in this organisation and in other organisations. These organisations may be universities involved in health and care research in this country or abroad. Your information will only be used by organisations and researchers to conduct research in accordance with the UK Policy Framework for Health and Social Care Research.

This information will not identify you and will not be combined with other information in a way that could identify you. The information will only be used for the purpose of health and care research, and cannot be used to contact you or to affect your care. It will not be used to make decisions about future services available to you, such as insurance.

You can find out more about how we use your information by contacting us directly – our contact details are available here, or by contacting the Data Protection Officer for Imperial College London at: .

Further information can be found via the Imperial College London webpages:



What were the aims of the ASCEND2 study?

Bowel cancer is the third most common cancer in the UK, and the second most common cause of cancer death in the UK. Early diagnosis improves survival and in light of this the NHS established the Bowel Cancer Screening Programme (BCSP). At the time of the ASCEND2 study, the BCSP offered screening using a stool testing kit (the faecal occult blood test) to 60-74 year olds in England.

The aim of the ASCEND2 study was to increase screening uptake in the BCSP and to reduce differences in uptake between socioeconomic groups, whilst ensuring that uptake does not decline in any particular socioeconomic group.

What type of study was ASCEND2?

ASCEND2 was designed as a randomised controlled trial. The intervention group received a GP endorsement statement with the letter accompanying their screening kit from the BCSP.


In the ASCEND study, four different invitation/information strategies were tested and compared with the standard bowel cancer screening invitation letter to see if screening participation improved.

GP practices were recruited as part of the ASCEND study and those that consented were included in ASCEND2.


No other aspects of the NHS Bowel Cancer Screening Programme were changed during the study. People received the same care as part of the screening programme regardless of whether they received an alternative invitation, or had their information used as part of the study.

When and where did this study take place?

The ASCEND2 study took place across England between February and March 2016.

What type of information does the CSPRG hold for the purposes of the ASCEND2 study?

The CSPRG does not hold personal data for the purpose of the ASCEND2 study.

What are the results of the study and what impact have they had?

The ASCEND2 study completed in April 2018 and when the results have been analysed, the detailed findings will be published in peer-reviewed medical journals. A summary of the findings will also be placed on this website.

We hope the results will be used to inform the NHS Bowel Cancer Screening Programme on how best to invite people for screening in the future and to improve