EDITOR'S PAGE
Medicine and Freakonomics
Anthony N. DeMaria, MD, MACC, Editor-in-Chief, Journal of the American College of Cardiology*
* Address correspondence to: Dr. Anthony N. DeMaria, Editor-in-Chief, Journal of the American College of Cardiology, 3655 Nobel Drive, Suite 400, San Diego, California 92122 (Email: ademaria{at}acc.org).
 For months I had been hearing people talk about a controversial book titled Freakonomics (1). Written by Steven Levitt and Stephen Dubner, the New York Times bestseller is subtitled "a rogue economist explores the hidden side of everything." Among controversial assertions that attracted attention were the claims that the striking reduction in violent crime witnessed in the 1990s was due to the Roe v. Wade decision legalizing abortion, that parenting contributes only modestly to the achievements of children, and that both teachers and sumo wrestlers cheat in response to individual incentives. So I picked up a copy and read it. Although Freakonomics does not deal with health care issues directly, the principles espoused apply well to medicine.
The primary concept underlying Freakonomics is that things are often not what they seem to be, and that the appropriate examination can yield evidence as to exactly what they are. As medical scientists, this seems a bit obvious. We are accustomed to distinguishing associations from causality and to determining whether the effects attributed to specific actions are actually produced by those actions (e.g., does revascularizing a stenotic coronary prolong life?). Therefore, I found the "hidden truths" uncovered in the book cute, but not that surprising. Although the methods of identifying the actual truth are described as tools of economics, in fact these are conventional analytic methods that are applied in all types of science. However, it is an interesting exercise to see how the economic principles delineated in the book apply to cardiology.
The first concept put forth was that "incentives are the cornerstone of modern life." This, of course, is the basic principle behind capitalism, and is generally believed to be responsible for the success of the system. The authors define 3 categories of incentives: economic, social, and moral. In an example, the imposition of a $3 fee when parents are late picking up children from school increased the frequency of late pick ups since a (too small) economic incentive was substituted for a moral one. Incentives are also felt to play an important role in cardiology, both in practice and research. However, I believe that the influence of economic incentives is overemphasized; my experience is that they are operative in medicine well after moral and social motives. I believe we in medicine adhere more closely to moral motives than do other fields. In fact, I think the social incentives of respect, fame, and academic advancement often outweigh economic inducements.
One side effect of incentives, particularly for economic incentives, is deception. The example given is of teachers who, incentivised by rewards for high student scores on standardized tests, cheat on the examination. While this behavior is repulsive in teachers, it would be horrific in physicians. However, overutilization of resources could be viewed as a form of deception in response to an economic incentive. That is why I think it is so important for us in cardiology to deal with the issue of self referral openly, directly, and with as much data as possible to avoid the appearance of inappropriate behavior.
The second principle espoused is that "the conventional wisdom is often wrong." We could translate this to medicine as things which seem obvious are often untrue. It seemed intuitive that eliminating premature ventricular contractions would increase survival in postmyocardial infarction patients and that beta-blockers would adversely effect heart failure patients, but neither was true. Again, I think we are more cognizant of this concept in medicine than in most other disciplines. In cardiology we typically require validation for everything we do. So I believe one of the best tenets of modern cardiology is to doubt everything until you have proof.
The third principle is that "dramatic effects often have distant, even subtle, cause." The example given is the role of legalized abortion upon the subsequent reduction of the crime rate years later. (I found this example a bit tenuous.) From my perspective, this principle hits home most directly in the distinction between causation and association. It is very difficult to prove causation, and one of the most common problems we encounter at JACC is the allegation of causation when only association can be proven. We confront this dilemma daily in clinical care. A patient has mitral prolapse and syncope; does one cause the other? Accordingly the practice of considering things which are both true as possibly related until proven so is a great strength.
A corollary of the distant cause is the unintended consequence. Right ventricular pacing is instituted to treat a bradyarrhythmia and can induce dyssynchrony and left ventricular dysfunction over time. I believe we are more careful and deliberate in implementing new modalities so as to avoid consequences than any other discipline in society.
The next principle is that "experts use their informational advantage to serve their own agendas." Several examples are given including funeral directors, financial advisors, automobile salesmen, and last but not least, heart doctors. Each group shares in common an enormous advantage in knowledge when dealing with the public which, it is alleged, they will always use to their own advantage. It pains me to see cardiologists included in this example, and I would argue that the interests of patients and doctors are nearly always aligned. However, one could envision instances, both clinical (such as recommending management) and research (such as enrolling patients), in which physicians could exploit their expertise to convince a patient to do something which is not in their best interest. Fortunately, the checks and balances and oversight in medicine are greater than in any other field, and we need to keep them strong.
In regard to this informational advantage, clearly the biggest change in my lifetime is the Internet. Patients can avail themselves of more and better medical information now than they could in the past. Many a clinic visit is now spent discussing with patients the material they have printed from the Internet. However, we in cardiology still have a huge informational advantage, and one that must be used wisely. I am euphoric, however, over the leverage I have in dealing with various salesmen in this era of the Internet.
The last principle is that "knowing what to measure and how makes a complicated world much less so." Freakonomics is essentially a book demonstrating how careful measurement and clear analysis can unmask truths that are hidden or wrongly interpreted by the conventional wisdom. Medicine is a data-driven discipline, so this principle is a bit of an "of course" for us. We should be very proud of this; there will never be a "freakiology."
Cardiovascular medicine and surgery is particularly evidence based. The plethora of large multicenter, randomized clinical trials (RCTs) attests to the importance of objective quantitative data in guiding practice. There is virtually no area of practice that is not informed by RCTs. However, swords are often double-edged. The summary findings extracted from large clinical trials must be applied to individual patients with specific characteristics. Our role in tailoring the trial data to individual patients is still of paramount importance, and I worry that it is sometimes lost in the sea of evidence. In addition, the absence of evidence is not the equivalent of negative results. It sometimes appears that we are paralyzed from taking any action in the absence of trial data. Until evidence is available, it seems reasonable to exert our best clinical judgment and manage patients in the most rational way possible.
Freakonomics is an entertaining read. It applies standard analytic methods to everyday issues to demonstrate that facts held to be true by conventional wisdom are actually false. It proposes a handful of principles to be applied in the assessment of "the world." Although most of the concepts espoused are well established in medicine, extrapolating these principles to medicine provides interesting points of emphasis. In terms of a quantitative, objective approach to understanding the world and reaching decisions, we in cardiology are well ahead of the curve.
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References
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- Levitt SD, Dubner SJ. Freakonomics: A Rogue Economist Explores the Hidden Side of Everything. New York, NY: HarperCollins Publishers Inc; 2005.
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