Carefully Crafted Messaging Boosts Uptake in Cancer Screening

Embedding psychological nudges in mail reminding people to get tested improves compliance

Colorectal cancer is the third deadliest cancer in the U.S., fueled in part by the fact that the invasiveness of a colonoscopy deters many people from submitting to a screening test that can lead to early(ier) detection before physical symptoms emerge.

The Centers for Disease Control and Prevention report that, overall, less than 70% of the target demographic who should be screened for colon cancer — adults between the ages of 50 and 75 — are up to date with recommended testing. Among the population receiving medical care through federally funded health clinics, less than 50% of patients are screened, according to the National Colorectal Cancer Roundtable.

Researchers spanning the medical and behavioral psychology fields have been exploring potential ways to boost colon cancer screening.

The emergence of a less invasive screening test that can be completed at home has improved screening uptake. The fecal immunochemical test (FIT) can detect hidden blood in stool — which can be an early signal of colon cancer. It also happens to be a less time-consuming and costly endeavor than a colonoscopy. All of that makes the FIT a compelling first-line defense in colon cancer detection for patients resisting colonoscopy screening. Patients who complete a FIT and have a positive result are then encouraged to get a colonoscopy.

A 2018 paper published in the Journal of the American Medical Association (JAMA) found that a riff on the behavioral ”opt-out” nudge increased screening compliance. Patients across more than two dozen community care clinics in California and Oregon who were proactively mailed a FIT kit were likelier to follow through with the screening than patients whose doctor suggested or scheduled testing during a clinic appointment.

Another study published in 2018 teased out the effectiveness of sending a simple ”reminder” letter to Medicaid patients telling them they were overdue for colon cancer screening and giving them instructions for requesting a FIT kit, compared to sending the letter with a FIT kit. More than 1 in 5 people who received the kit and the nudge letter completed the test, compared to 12% of people who only received the letter.

Published in 2019, yet another riff on this opt-out nudge found similar positive results for proactively mailing out a FIT kit, with the added twist of dangling financial incentives for completing the test (a $10 gift card, for example), which didn’t boost uptake.

In an article published in 2020 in Clinical and Translational Gastroenterology, a team that includes five researchers affiliated with UCLA medical systems and UCLA Anderson’s Noah Goldstein and Suzanne Shu report that the actual wording used in letters that accompany a FIT kit mailing can move the needle as well.

The team focused on more than 1,800 patients in the UCLA medical system who were overdue for colon cancer testing. The control group was sent the “usual care” treatment: a FIT kit in the mail with a somewhat generic letter explaining the importance of screening, and information on how to schedule alternative screening methods such as a colonoscopy or flexible sigmoidoscopy.

The intervention group received the same FIT kit, but the accompanying letter included language designed with explicit behavioral nudges.

The intervention mailing zeroed in on the problem of choice overload. The control group was presented with a kitchen sink of different tests they could choose from if they didn’t want to go the FIT kit route. The intervention group was instead presented with a more digestible binary decision: “You have options. You can be screened at the office with a colonoscopy or at home with your FIT kit.”

The intervention letter also played to our human inclination to value something if we think it is less common. The control group received an anodyne message: “Colon cancer screening is recommended every 1 to 10 years (depending on the type of testing) for most people starting at age 50.” The intervention group’s message leaned on a personal appeal to the implied scarcity bias. “You have been selected to complete a colon cancer screening that could save your life.”

The control group was told, “It is not recommended that you do a FIT kit if you prefer to be screened with colonoscopy.” The intervention group was presented with an explicit directive: “Please return the included kit in the next 2 weeks.”

For the ensuing six months after the FIT kits and letters were mailed, the researchers tracked patient behavior. In each of the six months, patients who got behavioral nudges were more inclined to follow through and get tested.

In the first month, 10% of the control group had taken one of the tests offered, compared to 15% of patients who were nudged. At month 6, uptake was 19.5% in the control group and 24.1% in the intervention arm.

The “easier” FIT kit was preferred over the colonoscopy. FIT uptake was higher for those who got the nudge-laden letter (14.7% in the first month) than for people who received the standard letter (9.2%). At month 6, 22% of people who received behavioral nudges had completed the FIT test, compared to 16.3% of people who received the more basic letter.

“Although it is difficult to say which of the changes we implemented contributed most to the higher screening rate we observed in the intervention group, we hypothesize that the use of defaults, limited time windows, and alternative overload reduction had the largest impact because these changes focused on simplifying the choice of how and when to get screened,” the researchers wrote.