RecruitingNCT06447064

Cancer Loyalty Card Study 2 (CLOCS-2)

Cancer Loyalty Card Study 2: a Retrospective Observational Case-Control Study


Sponsor

Imperial College London

Enrollment

2,900 participants

Start Date

Feb 4, 2026

Study Type

OBSERVATIONAL

Conditions

Summary

Cancer is one of the leading causes of mortality worldwide and is responsible for an estimated 9.6 million deaths yearly. Cancer-related deaths can be reduced if patients are diagnosed and treated early. Delay in cancer diagnosis can occur at any point along the diagnostic spectrum, from the first observation of symptoms to the start of treatment. Diagnosing cancer when it is still at an early stage, before it has spread, gives surgery, radiotherapy and other treatments the best chance of working. Therefore, early diagnosis is the most important way to improve cancer outcomes.Most of the cancers usually presents with vague and non-alarming symptoms. Most individuals are diagnosed late when the cancer has already spread, and the prognosis is poor. There are over 200 different types of cancer that can cause many different signs and symptoms. Sometimes symptoms affect specific body areas, such as abdomen or skin. But signs can also be more general, and include weight loss, tiredness (fatigue) or unexplained pain. The type of symptoms varies from person to person. The major reasons for not presenting to the GP with symptoms such as these are "not wanting to waste the GP's time" and normalisation of these symptoms. The persistence of a symptom, social influence and awareness encourage help-seeking behaviours in primary care. However, few believe their symptom(s) might be a sign of cancer. Consequently, people might choose to self-manage their symptoms by using over-the-counter medication, and to seek advice from other sources, (pharmacists, family, internet), rather than a primary care physician. RATIONALE FOR CURRENT STUDY An early cancer diagnosis is essential for receiving treatment as early as possible to have the best chance for successful treatment. Early diagnosis of cancer can be challenging. Sometimes, the cancer symptoms resemble common illnesses and could resolve with the use of over-the-counter medications and other remedies until they become persistent or debilitating. The present study focuses on ten cancer forms: colon, oesophageal, stomach, liver, bladder, uterine, vulval, ovarian, endometrial and pancreatic. Patients diagnosed with the cancers mentioned above often report experiencing vague symptoms (such as abdominal or back pain, indigestion, feeling full etc). They often use over-the-counter medication to manage their symptoms before seeing a doctor. Information about how often and what products participants purchase (e.g. pain killers, digestive products and natural remedies) to care for these symptoms could help identify these cancers a few crucial weeks or months earlier and encourage people to seek help sooner from their doctors.


Eligibility

Min Age: 18 Years

Plain Language Summary

Simplified for easier understanding

This study (CLOCS-2) investigates whether shopping data from supermarket and pharmacy loyalty cards (like Tesco Clubcard or Boots Advantage Card) can reveal patterns associated with cancer risk or early diagnosis. Researchers will compare shopping habits between cancer patients and people without a cancer diagnosis. **You may be eligible if...** - You are over 18 and live in the United Kingdom - You are registered with an NHS GP practice - You are a primary account holder of an eligible loyalty card (Tesco Clubcard or Boots Advantage Card) - You either have been diagnosed with one of the eligible cancer types (bladder, bowel, endometrial, liver, oesophageal, ovarian, pancreatic, stomach, uterine, or vulval) in the last 24 months, OR you have had no cancer diagnosis in the last 6 years **You may NOT be eligible if...** - You are under 18 or do not live in the UK - You do not hold an eligible loyalty card - You are not the primary cardholder and the primary cardholder in your household is unwilling to join Talk to your doctor to see if this trial is right for you.

This summary was AI-generated to explain the trial in plain language. It is not medical advice. Always discuss eligibility with your doctor before enrolling in a clinical trial.

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Interventions

OTHERCases & Controls

Participants will complete a brief online questionnaire at REDCap about their health, clinical history and lifestyle choices. The participant will only need to provide a photo ID and utility bill for ID verification, if the retailer cannot match participant details. After recruitment the participants purchase history in the past 6 years will be requested from the retailers.


Locations(1)

Imperial College Healthcare NHS Trust

London, United Kingdom

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NCT06447064


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