Mailing diagnostic tests increases the number of colorectal cancer screenings

In a new study aimed at determining the most effective approach to promoting colorectal cancer screening among adults aged 45 to 49, researchers at the University of California, Los Angeles (UCLA) found that simply mailing diagnostic tests based on stool analysis to people’s homes is the most effective strategy for increasing screening rates.

The study, published in JAMA, compared four strategies for increasing colorectal cancer screening rates in this population, which has only recently become eligible for screening. Of the four options tested, the researchers found that automatically sending a stool-based test by mail without the option to opt out of screening resulted in the highest screening rates.

Only about 15–17% of people were screened when they had to actively agree to screening or choose a screening test. But when they were automatically sent a test at home, more than 26% of people underwent screening.

When national guidelines first recommended screening for colorectal cancer in adults aged 45 to 49, it was unclear how best to reach and screen this new population group. Eliminating the need for patients to actively consent to screening may lead to better outcomes, especially when trying to engage young, generally healthy adults who do not yet recognize themselves as a cancer risk group.

The study, which involved more than 20,000 patients, is one of the first large-scale projects aimed at exploring effective ways to engage this new population in life-saving colorectal cancer screening.

This is vitally important as the incidence of colorectal cancer among young adults is on the rise. It is now the leading cause of cancer death in men aged 20 to 49 and the second leading cause in women of the same age group. In 2021, the US Preventive Services Task Force lowered the recommended age for screening from 50 to 45. However, participation among this new group covered by the program remains extremely low: less than 2% of people were screened in the 20 months after the recommendation change.

“There is an urgent need for data on how to reach adults aged 40 with effective and scalable screening strategies,” said May, an associate professor of medicine at the David Geffen School of Medicine at the University of California, Los Angeles (UCLA). The team tested four different outreach strategies by sending information through an electronic patient portal to 20,509 patients who had an average risk of developing colorectal cancer. The researchers wanted to find out which approach led to the highest number of people undergoing screening, what type of test they chose, and whether certain groups were more or less likely to participate.

The four strategies were as follows:

1. Ask patients to get screened with a stool test in the mail (known as a FIT kit).
2. Ask patients to get screened with a colonoscopy.
3. Ask patients to undergo screening and choose between FIT and colonoscopy.
4. Simply send patients a FIT kit by mail without asking for their consent. The researchers found that participants who were asked to actively consent to screening (strategies 1-3) had lower overall screening rates. Among those who were offered the option to consent to a home stool test (FIT), 16.4% underwent screening. In the group that was offered colonoscopy, the rate was 14.5%. When patients were offered a choice between FIT and colonoscopy, 17.4% underwent testing.

The most effective strategy was to send patients a FIT kit by default, without requiring them to choose between screening tests, which resulted in a screening rate of 26.2%.

The team also found that 73% of patients with abnormal FIT results underwent colonoscopy within six months, which is a key next step in cancer screening and an encouraging result given the typically low follow-up rates.

Although direct mailing of FIT kits showed better results, overall screening rates remained low, the researchers note. Nevertheless, this approach represents a significant step forward, highlighting a simple and inexpensive intervention that can help close critical gaps in screening and save lives. Further research is needed to optimize and adapt FIT mail distribution strategies to further increase participation rates.

The study showed that screening using FIT mail-out kits can be effective and accessible to a large portion of the population.