How Doctors Think (36 page)

I was regularly encouraged in my work by Ron Ansin, Betsey Apple, Barbara Bierer, Arthur Cohen, Everett Fahey, Lisa Goldberg, Lenny Groopman, Rabbi William Hamilton, Francine and Harry Hartzband, Margo Howard, Steve Hyman, Ben Mizell, Daryl Otte, Anne Peretz, Michael Share, Abe and Cindy Steinberger, and Liz Young.

For a decade,
The New Yorker
has been the laboratory where I experiment with writing about medicine and biology. Although my editors there were not directly involved in the crafting of this book, they continue to instruct me in the elements that make for quality writing. I learn so much from Emily Eakin, Dorothy Wickenden, Daniel Zalewski, Henry Finder, and of course David Remnick. I've also benefited over the years from lively interactions with Marty Peretz and Leon Wieseltier at the
New Republic.

The candor and insights offered by patients and physicians in these pages have made me understand medicine in an entirely new way. By opening up their lives to me, they have given me gifts of knowledge that I am privileged to share with those who are ill and in need. Any shortcomings in substance or style reflect my own deficiencies.

Notes

Introduction

Two recent articles about the shortcomings of algorithms and practice guidelines are Mary E. Tinetti, "Potential pitfalls of disease-specific guidelines for patients with multiple conditions,"
New England Journal of Medicine (NEJM)
351 (2004), pp. 2870–2874, and Patrick J. O'Connor, "Adding value to evidence-based clinical guidelines,"
Journal of the American Medical Association (JAMA)
294 (2005), pp. 741–743.

Those interested in the Bayesian approach can read Baruch Fischhoff and Ruth Beyth-Marom, "Hypothesis evaluation from a Bayesian perspective,"
Psychological Review
90 (1983), pp. 239–260; Fredric M. Wolf et al., "Differential diagnosis and the competing-hypotheses heuristic: A practical approach to judgment under uncertainty and Bayesian probability,"
JAMA
253 (1985), pp. 2858–2862. The observation by Robert Hamm that few physicians work in such a mathematical mode comes from "Clinical intuition and clinical analysis: Expertise and the cognitive continuum," in
Professional Judgment: A Reader in Clinical Decision Making,
ed. Jack Dowie and Arthur Elstein (Cambridge: Cambridge University Press, 1988), pp. 78–105.

The varied clinical manifestations of celiac disease are presented in Richard J. Farrell and Ciaran P. Kelly, "Celiac sprue,"
NEJM
346 (2002), pp. 180–188; Alessio Fasano, "Celiac disease—How to handle a clinical chameleon,"
NEJM
348 (2003), pp. 2568–2570; Ross McManus and Dermot Kelleher, "Celiac disease—The villain unmasked?,"
NEJM
348 (2003), pp. 2573–2574.

The work of Judith Hall and Debra Roter is extensive and scholarly. Their recent book is a comprehensive analysis of the field:
Doctors Talking with Patients/Patients Talking with Doctors: Improving Communication in Medical Visits,
2nd ed. (Westport, Conn.: Praeger Publishers, 2006). Publications relevant to their remarks in this chapter include "Task versus socioemotional behaviors in physicians,"
Medical Care
25 (1987); "Physicians' psychosocial belief correlate with their patient communication skills,"
Journal of General Internal Medicine
10 (1995), pp. 375–379; "Communication patterns of primary care physicians,"
JAMA
277 (1997), pp. 350–356; "Relations between physicians' behaviors and analogue patients' satisfaction, recall, and impressions,"
Medical Care
25 (1987), pp. 437–451; "Liking in the physician-patient relationship,"
Patient Education and Counseling
48 (2002), pp. 69–77; "Physician gender and patient-centered communication: A critical review of empirical research,"
Annual Review of Public Health
25 (2004), pp. 497–519. Other useful sources include E. J. Emanuel and L. L. Emanuel, "Four models of the physician-patient relationship,"
JAMA
267 (1992), pp. 2221–2226; G. L. Engel, "How much longer must medicine's science be bound by a seventeenth-century world view?," in
The Task of Medicine: Dialogue at Wickenburg. Menlo Park, California,
ed. K. White Donald (Henry J. Kaiser Foundation, 1988). Redelmeier has also examined the importance of clinical dialogue. See "Problems for clinical judgment: Eliciting an insightful history of present illness,"
Canadian Medical Association Journal
164 (2001), pp. 647–651; "Problems for clinical judgment: Obtaining a reliable past medical history,"
Canadian Medical Association Journal
164 (2001), pp. 809–813.

Studies of expertise have been greatly advanced by K. Anders Ericsson, and the interested reader is directed to "The role of deliberate practice in the acquisition of expert performance,"
Psychological Review
100 (1993), pp. 363–406; "Deliberate practice and the acquisition and maintenance of expert performance in medicine and related domains,"
Academic Medicine
79 (2004), pp. S70–S81. Geoff Norman is another leader in this area, and he recently reviewed how doctors can improve their skills in Geoff Norman et al., "Expertise in medicine and surgery," in
The Cambridge Handbook of Expertise and Expert Performance,
ed. K. Anders Ericsson et al. (Cambridge: Cambridge University Press, 2006), PP. 339–353.

The Institute of Medicine report is a landmark book:
To Err Is Human: Building a Safer Health System
(Washington, D.C.: National Academy Press, 1999). Donald Berwick has done wonderful work about system errors and how hospitals can protect patients from technical mistakes; a good example is "Taking action to improve safety: How to increase the odds of success," in
Enhancing Patient Safety and Reducing Errors in Health Care
(Chicago: National Patient Safety Foundation, 1999), pp. i-ii.

Arthur Elstein studied clinical reasoning, testing physicians' acumen with written descriptions of cases as well as with actors posing as patients with various diseases. Overall, Elstein estimated the rate of error in diagnosis at 15 percent, meaning one in six to seven patients was incorrectly assessed. Elstein's estimate agrees with classic studies of diagnostic errors of 10 to 15 percent, based on autopsies that revealed the missed diagnosis: A. S. Elstein, "Clinical reasoning in medicine," in
Clinical Reasoning in the Health Professions,
ed. J. Higgs and M. A. Jones (Woburn, Mass.: Butterworth-Heinemann, 1995), pp. 49–59; W. Kirch and C. Schafil, "Misdiagnosis at a university hospital in 4 medical eras,"
Medicine
75 (1996), pp. 29–40; K. G. Shojania et al., "Changes in rates of autopsy-detected diagnostic errors over time,"
JAMA
289 (2003), pp. 2849–2856; L. Goldman et al., "The value of the autopsy in three different eras,"
NEJM
308 (1983), pp. 1000–1005. Of note, the frequency of diagnostic errors did not change between 1960 and 1980 at an American university teaching hospital despite the introduction of new technologies like CT scans. In fact, overreliance on new procedures sometimes was the cause of serious missed diagnoses. Similar data were found in a study in a German teaching hospital. In the United States and Canada, more than one million people die in the hospital each year; missed diagnoses of a serious nature accounted for about fifty thousand deaths that could have been prevented if the actual case had been identified.

Although the frequency of misdiagnosis has been studied, few researchers have focused on its relationship to physician cognition. One of the first articles to do so was Jerome P. Kassirer and Richard I. Kopelman, "Cognitive errors in diagnosis: Instantiation, classification, and consequences,"
American Journal of Medicine
86 (1989), pp. 433–441. Pat Croskerry has worked with great commitment to categorize cognitive errors, particularly in his specialty of emergency medicine. Several of his important articles are "The importance of cognitive errors in diagnosis and strategies to minimize them,"
Academic Medicine
78 (2003), pp. 775–780; "Achieving quality in clinical decision making: Cognitive strategies and detection of bias,"
Academic Emergency Medicine
9 (2002), pp. 1184–1204; "When diagnoses fail: New insights, old thinking,"
Canadian Journal of CME,
November 2003. Donald Redelmeier recently wrote about detours in doctors' thinking in "The cognitive psychology of missed diagnoses,"
Annals of internal Medicine
142 (2005), pp. 115–120. Mark Graber, at the State University of New York, Stony Brook, raised the question of how to teach physicians to think about their thinking in "Metacognitive training to reduce diagnostic errors: Ready for prime time?,"
Academic Medicine
78 (2003), p. 781.

Most physicians are not aware of their cognitive mistakes; in addition, the medical system affords only inconsistent feedback to physicians about diagnostic errors and why they occurred. Thus, data on the frequency of flawed thinking come from retrospective analyses of medical records, from autopsies, and from hindsight physician interviews. Tejal K. Gandhi concluded that the majority of serious errors that led to malpractice claims were cognitive in nature; see "Missed and delayed diagnoses in the ambulatory setting: A study of closed malpractice claims,"
Annals of Internal Medicine
145 (2006), pp. 488–496. Mark Graber presented a study of one hundred misdiagnoses highlighting the high frequency of cognitive pitfalls in "Diagnostic error in internal medicine,"
Archives of Internal Medicine
165 (2005), pp. 1493–1499.

Studies of the use of computers to improve diagnosis have shown relatively small benefits, primarily among students rather than medical residents or attending physicians. In some instances the "computer consultation" was detrimental and caused the clinician to latch on to a misdiagnosis: Charles P. Friedman et al., "Enhancement of clinicians' diagnostic reasoning by computer-based consultation: A multiple study of 2 systems,"
JAMA
282 (1999), pp. 1851–1856.

1. Flesh-and-Blood Decision-Making

Robert Hamm's comments can be found in his chapter "Clinical intuition and clinical analysis: Expertise and the cognitive continuum," in
Professional Judgment: A Reader in Clinical Decision Making,
ed. Jack Dowie and Arthur Elstein (Cambridge: Cambridge University Press, 1988), pp. 78–105. Donald A. Schön presents his views in "From technical rationality to reflection-in-action," in
Professional Judgment,
pp. 60–77. "Flesh-and-blood decision-making," the phrase that Croskerry used, is explored in James Reason's seminal work
Human Error
(Cambridge: Cambridge University Press, 1990), p. 38. The use of heuristics is well articulated in two of Croskerry's articles: "Achieving quality in clinical decision making: Cognitive strategies and detection of bias,"
Academic Emergency Medicine
9 (2002), pp. 1184–1204, and "The theory and practice of clinical decision-making,"
Canadian Journal of anesthesia
52 (2005), pp. R1–R8. The Yerkes-Dodson law was published nearly a hundred years ago in Robert M. Yerkes and John D. Dodson, "The relation of strength of stimulus to rapidity of habit-formation,"
Journal of Comparative Neurology and Psychology
18 (1908), pp. 459–482.

There is considerable interest in using simulation to train physicians. The encounter with Stan is described in my article "A model patient: How simulators are changing the way doctors are trained,"
New Yorker,
May 2, 2005.

The research on physicians' attitudes toward patients with psychological problems is included in an article by Judith Hall and Debra Roter, "Liking in the physician-patient relationship,"
Patient Education and Counseling
48 (2002), pp. 69–77. Physicians in training are often directed to an article by J. E. Groves, "Taking care of the hateful patient,"
NEJM
298 (1978), pp. 883–887. Of course, there is an extensive literature related to mental health care, which is beyond the scope of this book. The interested reader can consult R. A. Flood and C. P. Seager, "A retrospective examination of psychiatric case records of patients who subsequently committed suicide,"
British Journal of Psychiatry
114 (1968), pp. 443–450; W. Ironside, "Iatrogenic contributions to suicide and a report on 37 suicide attempts,"
New Zealand Medical Journal
69 (1969), p. 207; John Maltsberger and Donald Buie, "Countertransference hate in the treatment of suicidal patients,"
Archives of General Psychiatry
30 (1974), pp. 625–633.

The connections between cognition and emotion are beautifully described in Antonio Damasio's
Descartes' Error: Emotion, Reason, and the Human Brain
(Itasca, Ill.: Putnam, 1994).

2. Lessons from the Heart

Amos Tversky and Daniel Kahneman were the pioneers in categorizing cognitive biases. Kahneman was awarded a Nobel Prize for their work; alas, Tversky died before the Nobel Committee's decision. Valuable articles by these researchers on errors include "Availability: A heuristic for judging frequency and probability,"
Cognitive Psychology
5 (1973), pp. 207–232, and "Judgment under uncertainty: Heuristics and biases,"
Science
185 (1974), pp. 1124–1131. Again, Pat Croskerry's "Achieving quality in clinical decision making: Cognitive strategies and detection of bias,"
Academic Emergency Medicine
9 (2002), pp. 1184–1204, is a compendium of thinking errors with special reference to the emergency department. Redelmeier's self-awareness about his feelings is found in his published work, including "Problems for clinical judgment: Introducing cognitive psychology as one more basic science,"
Canadian Medical Association Journal
164 (2001), pp. 358–360. Wilson's disease is a disorder involving copper metabolism resulting in a buildup of the metal in the liver and other organs.