Mobile messenger-initiated reminders improve longitudinal adherence in a community-based, opportunistic colorectal cancer screening program: A single-blind, crossover randomized controlled study

Cancer. 2021 Mar 15;127(6):914-921. doi: 10.1002/cncr.33336. Epub 2020 Nov 20.


Background: The fecal immunochemical test (FIT) is a cost-effective colorectal cancer (CRC) screening tool. However, longitudinal adherence, a factor that is critical to the success to any FIT-based screening program, often is poor. The authors hypothesized that reminders sent via mobile messengers, such as WhatsApp, improve such adherence.

Methods: In the current single-blind, randomized study, subjects from an opportunistic FIT screening program who had a negative FIT result the year prior were randomly allocated (1:1) to receive either a 1-off reminder via the WhatsApp messenger (WR) 1 month prior to the due appointments or no reminder (NR). All subjects were blinded to study participation and group allocation. At 24 months after randomization, a crossover of intervention was performed among those individuals who remained in the FIT program. The primary outcome was FIT adherence, defined as the pick-up and on-time return of the FIT. The secondary outcome was FIT adherence after the crossover.

Results: A total of 500 subjects were randomized to receive WR (250 subjects) or NR (250 subjects). Three individuals were excluded from analysis (1 died and 2 underwent colonoscopy). Both the FIT pick-up rate (80.3% vs 59.3%; P < .001) and return rate (79.9% vs 57.3%; P < .001) were significantly higher in the WR group compared with the NR group. After crossover of intervention (452 subjects), the WR group again was found to have a higher FIT pick-up rate (79.1% vs 52.9%; P < .001) and return rate (78.2% vs 52.4%; P < .001).

Conclusions: Text reminders sent via mobile messenger appear to improve the longitudinal adherence to FIT-based opportunistic CRC screening programs. The routine use of this technology in CRC screening should be considered.

Keywords: colorectal neoplasms; compliance; mass screening; smartphone; telemedicine.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Colorectal Neoplasms / diagnosis*
  • Cross-Over Studies
  • Early Detection of Cancer / methods*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Occult Blood*
  • Patient Compliance
  • Single-Blind Method
  • Text Messaging*