On 26th of January 2023 the results of the Cancer Loyalty Card Study (CLOCS) will be published in a scientific journal called JMIR Public Health and Surveillance.
In 2018 CLOCS was funded by Cancer Research UK and was initiated in 2019. The aim of this study was to help reduce delays in ovarian cancer diagnosis using purchase information collected on high street retailers' loyalty cards. We thought that women might be using over-the-counter medication to care for their symptoms before they went to the GP, and possibly even before they considered the symptoms could be serious.
The symptoms of ovarian cancer include feeling full more quickly, having a decreased appetite, persistent bloating, weeing more often, tummy (abdomen) pain. Many of these symptoms are considered non-specific and could also be caused by other more common illnesses.
What did we do?
We recruited research participants from November 2019 to January 2022, including 182 ovarian cancer patients and 427 women without ovarian cancer. Participants filled out a questionnaire and provided permission for the CLOCS team to request their purchase history using their store loyalty card details. Working with two UK-based high street retailers, the CLOCS team requested loyalty card data, going back up to 6 years, on behalf of ovarian cancer patients and women without ovarian cancer.
What did we find?
Purchases of medications for pain and indigestion were greater in the women diagnosed with ovarian cancer up to 8 months prior to their diagnosis. If we compare that to when patients in our study remembered experiencing their first symptoms (on average, about 4.5 months before diagnosis) and when they first went to the GP (about 3.5 months before diagnosis) about these symptoms, then we observe that the patients were potentially managing their symptoms for about 4 months with over-the-counter medication before they sought help from the GP.
What does this mean?
Firstly, it shows that using loyalty card purchase information can be helpful for research into early diagnosis of cancer. This is the first time that purchase information has been used for cancer research and we hope that by making new discoveries we will encourage more people to share their data for research. Secondly, it means that if we can harness this information better, we may be able to develop an alert encouraging people to visit the GP to discuss their symptoms sooner than they might otherwise have done.
What are we doing next?
The CLOCS team have been funded by Cancer Research UK to conduct a new study investigating other cancer types which we believe may also benefit from building a better understanding of reasons for delayed diagnosis. More details on that soon.
If you are concerned about symptoms you are experiencing, please seek help and advice from health professionals.
Press Coverage
Imperial College London - Loyalty card data could help to identify ovarian cancer symptoms sooner