Gastroenterology
Volume 137, Issue 3 , Pages 763-765, September 2009

Surveillance in Barrett's Esophagus: Lessons from Behavioral Economics

Houston Center for Quality of Care and Utilization Studies, Michael E. DeBakey VA Medical Center and Baylor College of Medicine, Houston, Texas

published online 29 July 2009.

Article Outline

 

Several observations in clinical practice seem to be difficult to explain on a rational basis. These include doing “too much,” such as repeated testing, parallel testing, expensive and extensive testing for unlikely rare disorders, as well as doing “too little,” such as screening for common cancers, vaccination, or counseling. Some of the practices seem baffling at first glance, especially given the presence of decision analysis models, cost-effectiveness models, and occasionally evidence-based published guidelines that delineate rational medical decision making. Conventional economics (ie, rational utility theory) assumes that decisions are arrived at through a rational process of weighing benefits against costs for the goal of maximizing one's utility. Medical decision making is modeled by similar assumptions; namely, physicians (and patients) should make decisions that maximize utility by balancing benefits/harms against costs. However, there has been a growing interest in behavioral economics, which concerns itself with describing how decisions are actually made. Behavioral economics assumes that we (people) are “predictably irrational”1 in the way we make decisions on several things, including those decisions pertaining to health, and that understanding the basis for this nonrational behavior might be used to make us “do the right thing” despite ourselves. Daniel Kahneman was awarded the Nobel Prize in Economics in 2002 for his and Amos Tversky's empiric work describing how individuals make nonrational decisions. Kahneman and Tversky (1973) demonstrated that individuals use mental short cuts (heuristics) to efficiently and reliably make decisions that are often in contrary to models that determine preferences based on weighing benefits against costs.2 Furthermore, their Prospect theory (1979) illustrated how individuals predictably overweigh losses and underweigh gains.3 They use the term “prospect” to refer to a set of outcomes with a probability distribution, and they state that even when the probability of gain is low, most people choose the prospect that offers the larger gain.

We illustrate these concepts with an example of seemingly nonrational behavior in gastrointestinal (GI) practice, highlight the relevant explanations from behavioral economics, and conclude with proposed ways to intervene based on these theories.

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Observation 

Patients with Barrett's esophagus (BE) have a very small risk of esophageal adenocarcinoma of approximately 0.5% per year. Endoscopic surveillance of patients with BE but no dysplasia, even at 5-year intervals, is an expensive practice. Models of cost effectiveness have shown that endoscopic surveillance programs in the United States either do more harm than good compared with no surveillance or are unlikely to be cost effective at usual levels of willingness to pay. Similarly in UK studies, nonsurveillance dominated surveillance (ie, cost less and conferred more benefit), or in other words, surveillance programs do more harm than good.4

Yet patients and providers remain highly concerned. Surveillance of BE is responsible for a large volume of endoscopy and office visits. One possible explanation is that reimbursement and defensive medicine drive5 many of these seemingly irrational practices. However, surveillance in BE and/or esophageal adenocarcinoma has been reported in health care systems where there are no financial incentives to doing more and medical malpractice cases are rare.

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Explanation 

Cognitive heuristics (mental short cuts) are rules of thumb that are used to make various types of judgments. Mental short cuts can be used properly to simplify judgment under uncertain circumstances. However, people make systemic errors in judgment based on common mental biases.6 The following classic mental short cuts explain a lot of apparently nonrational behavior related to BE.

Default Options 

People in general are highly prone to go with customary or defaults decisions that require inaction than to actively make a choice for an alternative action, even when the alternative action is good for them.7 Rational economics assumes that people weigh utilities for every given choice frame and then pick the utility maximizing choice. Using this argument, it would be clear that screening and surveillance in BE is not a good choice. However, behavioral economics says that we overweigh default options even if we have higher utilities for the nondefault option. For the patient, this makes the physician recommendation to undergo surveillance a very important factor in patients opting for surveillance. For the physician, expectations set by professional society guidelines and community practice standards may play a similar role.

Anchoring Heuristic 

We commonly use mental short cuts that depend on anchors for our choices. The presence or absence of risk estimates in health information creates these anchors. Expected rates of esophageal cancer, in our example of BE serve as mental as well as emotional anchors. A survey of patients with BE participating in an endoscopic surveillance program found that 68% of patients overestimated their 1-year risk of cancer, with a mean estimated 1-year cancer risk being close to 14%, way higher than reality.8 The initial “anchor” has a disproportionate bearing on ultimate judgments and inadequate risk adjustment with additional information can result when initial anchors are inaccurate such as the case in BE.

Availability Heuristic 

People often make judgments of frequency or risk based on whatever information is most accessible or available to them. Vivid or sensational events leave a more lasting impression than more common, mundane events.6 Therefore, physicians who have been burned with a missed diagnosis of esophageal adenocarcinoma would be more likely to overweigh the risk of cancer in BE, and consequently test too many people. Similarly, patients who have a family member with cancer may have a disproportionate risk aversion behavior toward this cancer. The tendency to make this mental short cut creates biases in computing risks by overweighing the co-occurrence of cancer. The interaction of availability bias and inaccurate anchors is an important theme in physicians' explanations for why they often do not follow established clinical guidelines.9

Endowment Effects 

Once a patient's symptoms or complaints are given a diagnostic label, the diagnosis produces an endowment effect on the patient and physician; now they own the diagnosis. Endowment effects skew decisions based on the perception of gain or loss.10 In the example of BE without dysplasia, patients and physicians who own the diagnosis of BE overweigh the chance of dysplasia and cancer and underweigh the probability that no harm will occur. Their behaviors related to surveillance become more consistent with underlying values for avoiding regret attributed to the cancer diagnosis rather than a rational calculation of utilities.11 Furthermore, the presence of real or perceived risk factors for cancer (endowment effects) correlates with perceived cancer risk. For example, patients who overestimated cancer risk in BE were more likely to have more symptomatic reflux.8

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So We Are Irrational About Our Risk Estimates; What Can We Do About It? 

Behavioral economics advocates policy decisions that help us to break the cognitive biases explained above. The following proposed strategies exploit the cognitive biases that produce behavioral distortions in the first place.

Structural Barriers and Facilitators 

These can be configured in ways that make screening of low-risk patients more difficult and screening of high-risk patients easier without interfering in the dynamics of the doctor–patient relationship. For low-risk patients, such as those with BE without dysplasia, endoscopic surveillance strategies that involve frequent endoscopy can be made nondefault options and possibly rewarded. Similar to surveillance colonoscopy, insurers may enact screens to refuse payment for irrationally frequent endoscopy in patients without dysplasia.

Clearly, endorsement of professional societies and possibly modification of current BE surveillance guidelines is required. In fact, professional society guidelines can be designed in such a way that the right choice is the default one. Although these interventions may seem paternalistic at first glance, they do not directly interfere with the doctor–patient encounter or physicians' determinations of medical appropriateness. Furthermore, the paternalism is asymmetric in that patients and doctors who maintain strong preferences for low-effectiveness strategies are still free to pursue them in the same manner that patients in managed care plans can still see out-of-network physicians.12

Avoidance of Labeling Precancerous Conditions 

Not withstanding pathophysiologic terms required for research in this area, patients with endoscopic and histologic findings consistent with BE without dysplasia should not be labeled with a diagnosis; in particular, the term “precancerous” can be avoided. Technically accurate information about the endoscopic and histologic findings and the dysplasia/cancer risk estimates can be given to provide information without endowing the label of a pathologic condition.

Point-of-Care Decision Support 

Decision support tools can be included as standard language on endoscopy or pathology reports. These tools can target both physicians and patients using simple language and multiple presentations of the same numerical estimates of lifetime probabilities of cancer; these estimates can serve as accurate risk anchors that frame future discussions. Potential harms related to frequent surveillance can also be clearly described. Availability bias can be reduced by presenting absolute risk numbers for patients with BE who never progressed to cancer juxtaposed against the much smaller proportion of those with progression.

In conclusion, concepts and lessons learned from behavioral economics can be used to explain seemingly nonrational decision making in clinical practice and to design interventions aimed at encouraging decisions that are more consistent with clinical evidence and patient's values.

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Acknowledgments 

This paper was primarily supported with use of facilities at Houston VA HSR&D Center of Excellence (HFP90-020).

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References 

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  10. Ubel PA. Free market madness (Why human nature is at odds with economics—and why it matters). Boston: Harvard Business Press; 2009;
  11. Collins ED, Moore CP, Clay KF, et al. Can women with early-stage breast cancer make an informed decision for mastectomy?. J Clin Oncol. 2009;27:519–525
  12. Loewenstein G, Brennan T, Volpp KG. Asymmetric paternalism to improve health behaviors. JAMA. 2007;298:2415–2417

 Funding Dr El-Serag is supported by NIH NIDDK K24DK078154-03. Dr. Naik is supported by an NIA Career Development Award (5K23AG027144) and a Doris Duke Charitable Foundation Clinical Scientist Development Award.

PII: S0016-5085(09)01187-1

doi:10.1053/j.gastro.2009.07.031

Gastroenterology
Volume 137, Issue 3 , Pages 763-765, September 2009

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