INDIGO randomised controlled digital clinical trial: INvestigating DIgital outcomes and quality of life in cancer survivors - a study protocol.

introductionThere are estimated to be 3.4 million patients in the UK living after a diagnosis of cancer. We know very little about their quality of life or healthcare usage. Patient-reported outcome measures (PROMs) are tools which help to translate a patient's quality of life into measurable categories, but how to do this at scale remains underexplored. The study employs a randomised design to assess different engagement strategies for optimising participation, data linkage and questionnaire completion in Northwest London and then nationally, with appropriate research approvals. METHODS AND ANALYSIS: We have designed and implemented an online, patient-completed, randomised observational trial. We will pilot it in Northwest London before national roll-out, using initially the General Practice (GP) record of a cancer diagnosis and then exploring the use of social media. The primary objective is to explore the feasibility of recruiting participants via self-identification or contact from the primary care research network and obtaining consent to link participants' PROMs responses to their cancer registry records. Data collection occurs through a secure platform, with participants directly responsible for data entry. There is no formal target sample size because this is a feasibility study, and we want to explore how many patients we can recruit. Analyses will be conducted using descriptive statistics, repeated measures multilevel modelling and machine learning techniques. If a substantial difference in responses between randomisation arms is detected, ineffective strategies will be removed. If no clear difference is observed, recruitment will continue with periodic reviews based on response rates and data completeness. ETHICS AND DISSEMINATION: The Study Coordination Centre has obtained approval from the London-Surrey Research Ethics Committee and Health Research Authority. We will publish and disseminate the results in local, national and international meetings, in peer-reviewed journals, on social media and on websites.It has been registered under 'Investigating Digital Outcomes for Cancer Survivors in the Community' (NCT06095024). TRIAL REGISTRATION NUMBER: NCT06095024: Investigating Digital Outcomes for Cancer Survivors in the Community.