Effectiveness of Using Mobile Health Technology in Colorectal Cancer Screening Uptake

In Hong Kong, Colorectal cancer (CRC) ranked second in both cancer incidence and mortality, accounting for 16.7% of all new cancer cases and 14.6% of all cancer-related deaths in 2019. There was a staggering 2.5-fold increase in the number of newly diagnosed CRC cases from 1584 to 2019. The fecal immunochemical test (FIT) helps reduce the incidence and mortality of CRC and is widely used for population-based CRC screening. The government-subsidized CRC screening program was launched in Hong Kong as a pilot in 2015 and fully implemented in 2020. The program was subsidized for asymptomatic Hong Kong residents, aged 50-75 years, to receive FIT screening every two years. A subsidized follow-up colonoscopy was offered for a positive FIT result. For a negative FIT result, the participant was advised to repeat the screening two years later. Despite the subsidy and promotion, the uptake rate of the population-based colorectal cancer screening was low. Only 275,000 (\~10%) underwent FIT screening under this program as of 31st December 2021. Efforts have been made to increase the rate. Outreach is the active dissemination of screening outside of the primary care setting, and it also includes mailing, texting, and calling to encourage scheduling of screening procedures. All eligible subjects will be randomized and allocated to receive either intervention (chatbot) or standard of care (text reminder) in a 1:1 allocation ratio. A fully automated chatbot will be developed and maintained in collaboration with IT experts on the WhatsApp Messenger platform for its wide popularity in local older adults and user-friendly interfaces for extensions. Depending on the randomization group, it delivers either a standard text reminder of CRC screening or health education in text and video formats with a series of questions on personalized risk assessment of CRC and information of primary care physicians under a government-subsidized CRC screening program according to the subject\'s preferred district. The same professional team will maintain the health status of the chatbot during the intervention period. A monthly review of chatbot performance will be conducted. A feedback loop is also incorporated into the chatbot, and users are invited to leave comments. Accordingly, improvements will be made, and the questions raised by the subjects will be collected and used to construct a data bank for the future development of Artificial intelligence (AI)-enabled chatbots.