A financial incentive – offering patients a 10% chance of winning a $50 lottery if they completed a fecal occult blood test – improved compliance with the colorectal cancer screen by approximately 20%, according to a report published online Nov. 17 in Annals of Internal Medicine.

In a randomized controlled trial assessing six different financial incentives for completing fecal occult blood tests (FOBTs), only this “lottery” incentive improved compliance. It is based on a central tenet of behavioral economics: people attach more value to near-term than long-term costs and benefits. In this specific case, patients may fail to complete FOBTs because the tests entail “a certain and immediate disutility” (i.e., a cost) in return for “an uncertain and distant benefit of early detection of colorectal cancer for a few patients and no tangible benefit for most patients, who screen negative,” said Dr. Jeffrey T. Kullgren of the Center for Clinical Management Research at the Veterans Affairs Ann Arbor (Mich.) Health System and his associates.

Their findings demonstrate that “a low-cost, scalable innovation … can improve health care quality by promoting patient adherence to a high-value clinical preventive service” in a real-world primary care setting.

The investigators performed the two-stage trial during an 8-month period at a single primary care VA clinic. Most of the participants were white males in their 60s, and nearly half had a disease or injury related to military service. Approximately one-third had not completed a prescribed FOBT at their previous annual physical examination.

In the first stage of the study, 713 patients prescribed an FOBT were randomly assigned to usual care or to receive $5, $10, or $20 incentives for completing their FOBT within 30 days. The intent was to determine which of these dollar amounts was the smallest effective “dose” to enhance compliance, so that that amount could be further tested in the second stage of the study. However, none of these amounts proved effective. So in the second stage, 836 patients were assigned to usual care or to one of three incentives using the lowest amount ($5): a fixed payment of $5, a lottery with a 1 in 10 chance of winning $50, or a raffle in which one patient would win $500.

Only the lottery incentive for a 10% chance of winning $50 improved patient compliance with the FOBT. The rate of completing an FOBT within 30 days in this group was 19.6% higher than the rates in the other groups, Dr. Kullgren and his associates said (Ann. Intern. Med. 2014 Nov. 17 [ doi:10.7326/M13-3015]).