Dive Brief:

• A $10 financial incentive failed to motivate patients to mail in colorectal cancer screening tests in a clinical study, leaving researchers to puzzle over whether a larger reward or payment upfront might have boosted response rates.
• Mailing fecal immunochemical test kits to patients' homes has been shown to increase participation in colorectal screening but requires resource-intensive outreach. Financial incentives have worked in other preventive health efforts, spurring interest in whether they might entice patients to complete fecal tests, the study authors said.
• However, there was no statistically significant difference in completion rates among all four arms of the 897-patient study, which compared three different incentive structures to no incentive.

Dive Insight:

Colorectal cancer screening is recommended by all major U.S. medical organizations, and while greater use of testing is saving lives, it remains underused. People who don't get screened more than double their risk of death from the disease, according to a study published in January in the journal Gastroenterology.

The cancer is the third most commonly diagnosed in the United States, and the third leading cause of cancer-related deaths, according to the American Cancer Society. Death rates have been dropping in part to earlier detection that enables removal of polyps before they can develop into cancer.

The group recommends that people at average risk for colorectal cancer begin screening at age 45 with either a stool-based test or visual test such as colonoscopy, noting that fecal testing must be done more often. The fecal immunochemical test is used to find small amounts of blood in the stool that could be a sign of cancer or polyps. A stool DNA test looks for DNA or gene changes that can be found in pre-cancerous growths and cancer cells. Abnormal results for either stool-based test require followup with a colonoscopy.

In the financial incentives study, patients ages 50 to 75 who had visited their primary care clinician at least twice in the prior two years were mailed a fecal immunochemical test with a letter and instructions for use. The patients were eligible for colorectal cancer screening but were overdue. A reminder letter was sent six weeks after the initial test kit mailing.

The patients received either no financial incentive, an unconditional $10 incentive included with the mailing, a $10 incentive conditional on test completion, or a conditional lottery with a one-in-10 chance of winning $100 after completing the test. The test completion rate at six months was 32.7% in the no incentive group, 31.7% in the unconditional arm, 26.8% in the conditional incentive arm and 24.3% in the lottery incentive group. None of the arms with an incentive was statistically superior to the arm without a reward.

The study authors theorized that the amount of the incentive may have been too small to be effective, or the effort may have worked better if a followup telephone call were used to explain the incentive offer. Patients also may have been put off by having to wait for the incentive in the case of the conditional groups, or by the unpleasantness of completing a stool test.