Adding a deadline to a mailed invitation for FIT colorectal cancer screening resulted in improved return rates.
The highest return rate was seen with a 2-week deadline.
This intervention can be easily implemented into routine practice.
The simple addition of a deadline to a mailed invitation for fecal immunochemical test (FIT) colorectal cancer (CRC) screening resulted in improved return rates, the randomized TEMPO trial showed.
Across eight study arms, the highest return rate was seen with a 2-week deadline without a problem-solving planning tool, with 68% of usable FIT kits returned by 3 months compared with 66% in the control group (no deadline and no planning tool), reported Kathryn Robb, PhD, of the University of Glasgow in Scotland, and colleagues in The Lancet.
"We estimate that a 2% increase in FIT returns would mean an additional 39,000 people participating in a 2-year Scottish Bowel Screening round, with approximately 23 colorectal cancer deaths being avoided as a result," they explained. "The implications of the findings for practice are that mailed invitations to FIT screening should consider including a deadline for FIT return -- a 2-week deadline might offer the best option in terms of impact and acceptability of the deadlines we tested."
"This is a considerable effect for an intervention which involves only adding one sentence to the invitation letter, which can be easily implemented into routine practice," they added.
Previous research has shown that completing one or more FIT screenings was associated with a lower risk of death from CRC.
The lowest return rate (63.2%) was observed when the planning tool -- an added sheet of paper that asked participants to identify concerns that kept them from completing and returning the FIT kit and gave a tip to help participants overcome those concerns -- was given without a deadline.
The primary analysis, assuming independent effects of the two interventions, suggested a positive effect of giving a deadline (adjusted OR 1.13, 95% CI 1.08-1.19, P<0.0001), and no effect with use of the planning tool (aOR 0.98, 95% CI 0.94-1.02, P=0.34), but this was complicated by an interaction between the two interventions (P=0.0041).
Among those who were given a deadline, there was no evidence that receiving a planning tool had any effect (aOR 1.02, 95% CI 0.97-1.07, P=0.53), but without a deadline, giving the planning tool appeared to be harmful (aOR 0.88, 95% CI 0.81-0.96, P=0.0030).
In an editorial that accompanied the study, Hermann Brenner, MD, and Michael Hoffmeister, MSc, PhD, of the German Cancer Research Center in Heidelberg, noted that "even though the observed increase in adherence was modest, the almost no cost inclusion of a return deadline would be expected to have a substantial public health impact in a population-wide colorectal cancer screening program."
"These results are of high relevance on a global scale, because they appear to be generalizable to many non-Scottish populations," they wrote.
In the nationwide, factorial TEMPO trial, Robb and colleagues used the mailed invitations for FIT CRC screening that the Scottish Bowel Screening Program sent out between June 19 and July 3, 2022. These invitations are sent by the program every 2 years to all adults ages 50 to 74 years in Scotland.
During the study period, 40,000 consecutive adults (mean age 61.2 years, 50.1% women) who were eligible for CRC screening were randomized to one of eight groups:
Standard invitation (the control group)
A 1-week deadline for the FIT return
A 2-week deadline
A 4-week deadline
The problem-solving planning tool but no deadline
The planning tool plus a 1-week deadline
The planning tool plus a 2-week deadline
The planning tool plus a 4-week deadline
Reminder letters were mailed to all recipients about 6 weeks after the invitation and FIT kit were sent, which is the usual practice within the screening program.
"By increasing uptake in response to the initial invitation letter, fewer reminder letters will need to be sent to non-responders at 6 weeks, and the burden on primary care and public health efforts outside the screening program to increase uptake will also be reduced, further reducing costs," the authors noted.
As for study limitations, Robb and team said they were unable to determine any interactions with ethnic background or evaluate any effect on future screening rounds.
Disclosures
The study was supported by the Scottish government and Cancer Research UK.
The study authors reported no conflicts of interest.
The editorialists reported no conflicts of interest.
Primary Source
The Lancet
Source Reference: Robb KA, et al "Behavioural interventions to increase uptake of FIT colorectal screening in Scotland (TEMPO): a nationwide, eight-arm, factorial, randomised controlled trial" Lancet 2025; DOI: 10.1016/S0140-6736(24)02813-7.
Secondary Source
The Lancet
Source Reference: Brenner H, Hoffmeister M "Cost-effective improvement of real-world cancer screening" Lancet 2025; DOI: 10.1016/S0140-6736(25)00108-4.