On the other hand, nearly everyone pays the full cost of their veterinary care, and taking your pet to the vet is a good time to think about how medical decisions should get made.

This came up for me recently. I have an 11-year-old Labrador retriever.  My wife took her to our usual vet practice because she had a strange swelling on her flew (upper lip). On this particular day, she saw a new young vet who we hadn’t seen before. He made three findings:

1. The swelling was an infection, and antibiotics were indicated. He prescribed Simplicef, which the manufacturer describes as “the first and only once-daily oral cephalosporin that’s FDA approved for veterinary use in the treatment of canine skin infections. It’s designed to be convenient and a good value for your large dog.” (from simplicef.com)
   
2. Her weight was 57 pounds, about 10 pounds lower than a year ago. He suspected a metabolic disorder (and probably also considered cancer, but didn’t say that), and ordered a panel of blood tests.
3. He heard a heart murmur, left-side, grade 2-3/6, which had been documented in her chart for several years. He recommended an ultrasound, chest x-ray, and ekg.

I like veterinarians. I think they’re good people with the interests of animals at heart. That said, in this particular consultation, several avoidable errors were made that illustrate some key principles of medical decision making (for humans as well as dogs):

1. The dog improved on the first 14-day course of Simplicef, as we all expected, but these infections typically require multiple courses. Readers of this blog will not be surprised to hear that while once-daily dosing may be more convenient than twice-daily dosing, a 14-day course of Simplicef was about $50; the equivalent course of generic cephalexin is about $8. There is no evidence of any difference in effectiveness, and cephalexin has been around a long time, and our dog has taken it before with no ill effects. We pointed this out to the vet, who was surprisingly reluctant to switch for the second course, but agreed. The infection continued to improve on cephalexin. Attention to principles of rational prescribing would have been beneficial here.
2. The blood tests were all normal, as I had predicted, because I knew something that the vet didn’t — but should have. About 10 months earlier, we changed to a prescription dog food (our dog has arthritis, the combination of glucosamine and omega-3’s we were adding to her regular dog food seemed to be helping, and the new dog food had that all built-in and was cheaper that the cost of the supplements). When we changed food, we continued to feed at the same volume, without considering differences in the caloric content of the food, which turned out to be lower. She was losing weight because she was simply not getting enough calories. I had the vet calculate the appropriate feeding amount and she was gaining weight within two weeks (although that requires titration too — her joints are less painful when she’s lighter, so we don’t want her to gain it all back). The key decision point here – one echoed by many expert human diagnosticians -  is that lab tests can’t take the place of a good history. Had this vet asked “have you changed her food?”, we would have embarked on this trial of increasing her food without the costly blood tests — which, given that she had no clinical fatigue or other symptoms, could certainly have been postponed a few weeks anyway.
3. Everyone likes to know what’s going on. Naturally, the vet would like to know the cause of the heart murmur. As we point out in the book, however, the main purpose of gathering information is to drive a decision (allaying worry might be a secondary purpose, but that should be the patient’s — or owner’s — worry, not the doctor’s). So I asked the vet what he expected to learn, and how that would affect subsequent treatment. He indicated that they would learn if her murmur was amenable to medical treatment. I pressed for exactly which drugs he was referring to, and he mentioned diuretics and ACE inhibitors. I asked if there was any evidence of benefit for an asymptomatic dog, and he assured me there were several studies. I asked where to find them; he couldn’t specifically cite any, but suggested I search Medline for canine heart murmur studies. Which I did, finding two medium-to-large trials, one showing no benefit and one showing ambiguous benefit (and with several methodological flaws). Now, the veterinary literature is considerably smaller than the human medicine literature, and many fewer well-designed large-scale randomized trials are conducted in dogs. I haven’t yet brought these studies with me to see if (a) I didn’t find some important study that the vet had in mind, (b) he was thinking of these studies and interprets the findings differently, (c) he was thinking of studies in dogs with documented heart disease, in which ACE inhibitors do appear to prolong life by several months, or (d) he was passing along a vague memory of reading these or being told that evidence supported the drugs without checking for himself. Moreover, his recommendation did not consider values in the decision beyond the value of gaining knowledge. Cardiac ultrasound requires sedation, which is a procedure that is not without risk in an older dog. Moreover, medications can have side effects that can diminish quality of life, and these may not be worth extending our dog’s life by a few months. These are crucial considerations in this decision, and this particular vet, on this particular day, missed them.

My wife is a very smart person, but, like most people, not a decision scientist – and she shouldn’t have to be. A veterinarian, like a physician, has far greater expertise and experience in health care than their clients do. When they make a recommendation, it will usually be followed – often without question. That’s one reason why veterinarians (and physicians) also need to become experts in decision making, and why owners (and patients) need to ask good questions and seek out providers who demonstrate a commitment to good decision making.

After thinking about it for a while, though, I realized that medical decision science (at least as I practice it) is primary about helping physicians and patients with to do three key things:

• know your Goals
• understand Uncertainty
• pay attention to Trade-offs

Which conveniently folds up into the acronym G-U-T: goals, uncertainty, trade-offs.

Normally, we think of making gut decisions as an intuitive, impulsive, “hot” process. Now, though, when I think of asking people what their gut is telling them, I’ll be thinking of their GUT: What are your goals for life, and how does that factor into this decision? What is uncertain in this decision, how much does it matter, and how can you know more or worry less? What trade-offs will you face between outcomes that you care about, and how will you make them?

(And should I add “S” for “society” and make it “GUTS?”)
Readers, what are your three words for making medical decisions?

The problem of choosing a physician is not a trivial one.

Patients have relatively little guidance to go on besides:

• Who do my friends see?
• Where is this physician located?
• Is this physician covered by my health care plan, if any?
• What is his/her specialty?
• What are his/her office hours?
• What is his/her name? (which is often informative about the physician’s gender and sometimes other demographics)

The article discusses some expanded strategies:

• Rating systems (by consumers, by payers, by peers)
• Hospital affiliations
• ABMS certification
• Interviewing the physician

The article concludes by quoting Dr. Samantha Collier, the chief medical officer for HealthGrades, who points out physicians “need to be a good match for you.” She’s talking about having a comfortable relationship, but the idea of patient/physician fit is one that I’ve been interested in for some time.

In 2006, colleagues and I wrote an a paper on the development of a measure of patient and physician fit. The process involved surveying both physicians and patients at my University, and asking about preferences for the physician’s behavior around six dimensions of interaction: considering non-medical aspects of the patient’s life, knowledge of herbal medicine, degree of physician decision making, providing information to the patient, considering patient’s religion, and treating the problem as the patient perceives it. We then looked to see how well patients and their physicians fit, whether fit was related to satisfaction, and whether there was room for improvement in fit.

The first interesting result was that both patients and physicians had a wide variety of preferences. This means that no physician could be a perfect fit to every patient.

The second interesting result was that fit on some dimensions was associated with satisfaction. Among patients seeing internists, fit on degree of physician decision making led to greater satisfaction; among patients seeing family physicians, fit on providing information led to greater satisfaction. It wasn’t that patients whose doctors provided more information (or shared decisions more) were more satisfied — it was patients whose doctors had similar preferences for these dimensions, whatever those preferences were. For example, patients who didn’t want to be given a lot of information were more satisfied when working with physicians who didn’t prefer to give a lot of information. Similar findings have been reported by Edward Krupat at Harvard in his work on the Patient-Practitioner Orientation Scale (PPOS).

The third interesting result was that patients and physicians who fit best may not automatically find each other. We found that in many cases, patients were not seeing the physician in their practice group who would have been their best fit.

Although we didn’t investigate the question directly, I suspect that fit only rarely and only slightly improves over time in the patient-physician relationship. Find the right physician for a patient is where the big improvements happen, and if better fit leads to more satisfying patient/physician relationships — and better relationships lead to better continuity, adherence, and care — we ought to be trying to provide patients and physicians with the guidance necessary to make those choices.

Taking fit seriously provides an important role for the physician as well. These dimensions of clinical behavior are often only implicitly observed or inferred by patients because many patients and physicians don’t discuss them explicitly. Physicians can help by letting patients know where they stand on such issues as providing information, and decision making. Physicians who practice in groups might consider developing an intake survey for patients that would enable them to place the patient with the best-fitting physician first.

The proverb captures important psychological nuances of choice. The same product – a bottle of wine or a risky medical procedure – may be perceived differently depending on its context, and it is often possible to arrange the context to influence a choice while still maintaining the decision maker’s autonomy.

The practice of structuring choices is called “choice architecture” in a brilliant and important new book, Nudge: Improving Decisions About Health, Wealth, and Happiness, by University of Chicago Distinguished Professors Richard Thaler (Business) and Cass Sunstein (Law). Nudge lays out the groundwork for the science of choice architecture in investing, insurance, health care delivery, and other areas, and argues for a “libertarian paternalism” in which choices are structured to make it more likely that a decision maker will select what is considered the most beneficial option, without impairing the ability to decision makers to select other options. For example, making enrollment in 401(k) plans automatic for new employees, with a form for opting out, is likely to result in greater retirement savings than an opt-in system, without limiting anyone’s freedom to choose.

Thaler and Sunstein apply the principles of choice architecture to a few problems in health care (How could Medicare part D be improved? How can organ donation rates be increased? Why shouldn’t patients be allowed to waive their right to sue for medical negligence in return for cheaper health care?) But the concepts in the book go beyond their specific examples and could prove very useful to practicing clinicians, who, they note, are often in the position of being choice architects for their patients.

Their principles of choice architecture (paraphrased by me and focused on physicians helping patients make decisions) are:

• Make sure incentives are aligned with desired outcomes
• Help patients map outcomes of different alternatives into formats they can understand (a major focus of Medical Decision Making as well)
• Arrange default options to favor better health. Pediatricians have done a good job of making vaccination a default option.
• Provide timely and relevant feedback about choices and outcomes. A patient seeking to lose weight needs to experience feedback in the form of measurable progress soon enough that they are not discouraged.
• Expect error and develop systems to prevent, detect, and minimize it. For example, pill cases and inhalers with dosage counters are simple and valuable ways to reduce the frequent errors people make in remembering medication. Psychological research provides direction as to what kinds of errors are to be expected when people are making decisions.
• Structure complex choices to reduce the difficulty of making good decisions. In many ways, that’s what medical decision making — and Medical Decision Making — is about.

I highly recommend Nudge. It’s a great read, and has the potential to change the way you think about clinical practice. Here’s a link to the Nudge web site and blog for more information.

Practically speaking, most medical decision models don’t (and perhaps can’t) consider patient goals directly. Good clinicians, however, must (and do).

Medical decision models typically adopt two goals that are both common and easily amenable to measurement:

1. Live as long as possible
2. Maintain as functional/good a state of health as possible

In fact, these two common goals form the basis of the QALY model for evaluating health outcomes (and thus guiding medical decisions), about which I’ll have more to say over time.

Focusing on the common goals makes sense for health policy decisions, and is a convenient simplification. Incorporting individual patient goals is hard: they differ from patient to patient, and usually only the patient herself has really good insight into her goals. But for good clinical decision making, incorporating individual goals is also necessary, because rational people are willing to sacrifice some of their life or health in order to achieve other important goals.

Key questions for the physician seeking to help a patient make significant medical decisions, then, are which goals are important to this patient, and how important are they relatively to one another?

I’ll discuss goal clarification — helping a patient determine what their key goals might be — in another post. Here I want to describe a method for determining the relative importance of a set of goals in the context of a particular medical decision.

The procedure I’ll be describing is a variation of swing weighting, and is fully described in the seminal decision analysis book Decision Analysis and Behavioral Research, by Detlov von Winterfeldt and Ward Edwards (sadly no longer in press, but available from many used bookdealers).

To use swing weighting with a set of goals and a set of treatment outcomes, you determine from the patient, how each treatment outcome would impact each of their goals.

For example, if a patient has three goals:

1. Live as long as possible
2. Continue working at my job
3. Keep my family financially secure

and is considering three treatments (A, B, and no treatment) with known outcomes, they might perceive the situation to look like this:

To determine the relative importance of their three goals, we ask which goal could result in the most important swing from worst possible achievement of that goal to best possible achievement. That is, if the patient were the worst possible scenario (no more than two years to live, unable to work for months, and sufficient insurance coverage), which one goal’s outcome would they want to swing to the best possible achievement? Would they prefer to improve their longevity (from “no more than 2 years” to “5+ years”), their ability to work (from “unable to work for months” to “immediately resume work”), or their financial security (from “sufficient coverage” to “sufficient coverage”)? If the patient prefers to swing Goal 1, that is considered her most important goal, and she can then proceed to choose which goal she would next choose to swing, out of those that remain.

The beauty of swing weighting is that it recognizes the range of outcomes on each goal is crucial in making judgments about their relative importance. Even if the family’s financial security is the patient’s most important goal in the abstract, its importance is low (actually nil) in the decision above, because none of the options will produce a change in that goal.