Jul 28, 2017

The scientific physician

There's no question that the Flexner report brought about a revolution in medical education. Kenneth Ludmerer, a medical historian and physician, stated:

At the heart of the transformation of American medical education was a revolution in ideas concerning the purpose and methods of medical education. After the Civil War, medical educators began rejecting the traditional notion that medical education should inculcate facts through rote memorization. The new objective of medical education became that of producing problem solvers and critical thinkers who knew how to discover and evaluate information for themselves. To achieve this goal, medical educators deemphasized traditional didactic teaching methods— lectures and textbooks—and began speaking of the importance of self-education and learning by doing. Through laboratories and clinical clerkships, students were to be active participants in their learning, rather than passive observers.


Flexner pointed out that the scientific method of thinking applied to medical practice. By scientific method, he meant the testing of ideas by well-planned experiments in which accurate facts were carefully obtained. The clinician’s diagnosis was equivalent to the scientist’s hypothesis; both diagnosis and hypothesis needed to be submitted to the test of an experiment. “The practicing physician and the ‘theoretical’ scientists are thus engaged in doing the same sort of thing, even while one is seeking to correct Mr. Smith’s digestive aberration and the other to localize the cerebral functions of the frog.”1(p92) Flexner argued that mastery of the scientific method of problem solving was the key for physicians to manage medical uncertainty and to practice in the most cost-effective way.

In his 1910 report, for the Carnegie Foundation, Abraham Flexner tried to introduce science as a way of thinking in the medical curriculum. He wrote:

The main intellectual tool of the investigator is the working hypothesis, or theory, as it is more commonly called. The scientist is confronted by a definite situation; he observes it for the purpose of taking in all the facts. These suggest to him a line of action. He constructs a hypothesis, as we say. Upon this he acts, and the practical outcome of his procedure refutes, confirms, or modifies his theory. Between theory and fact his mind flies like a shuttle; and theory is helpful and important just to the degree in which it enables him to understand, relate, and control phenomena.

This is essentially the technique of research: wherein is it irrelevant to bedside practice? The physician, too, is confronted by a definite situation. He must needs seize its details, and only powers of observation trained in actual experimentation will enable him to do so. The patient's history, conditions, symptoms, form his data. Thereupon he, too, frames his working hypothesis, now called a diagnosis. It suggests a line of action. Is he right or wrong? Has he actually amassed all the significant facts? Does his working hypothesis properly put them together? The sick man's progress is nature's comment and criticism. The professional competency of the physician is in proportion to his ability to heed the response which nature thus makes to his ministrations. The progress of science and the scientific or intelligent practice of medicine employ, therefore, exactly the same technique. To use it, whether in investigation or in practice, the student must be trained to the positive exercise of his faculties; and if so trained, the medical school begins rather than completes his medical education. It cannot in any event transmit to him more than a fraction of the actual treasures of the science; but it can at least put him in the way of steadily increasing his holdings. A professional habit definitely formed upon scientific method will convert every detail of his practising experience into an additional factor in his effective education.

From the standpoint of the young student, the school is, of course, concerned chiefly with his acquisition of the proper knowledge, attitude, and technique. Once more, it matters not at that stage whether his destination is to be investigation or practice. In either case, as beginner, he learns chiefly what is old, known, understood. But the old, known, and understood are all alike new to him; and the teacher in presenting it to his apprehension seeks to evoke the attitude, and to carry him through the processes, of the thinker and not of the parrot.

The fact that disease is only in part accurately known does not invalidate the scientific method in practice. In the twilight region probabilities are substituted for certainties. There the physician may indeed only surmise, but, most important of all, he knows that he surmises. His procedure is tentative, observant, heedful, responsive. Meanwhile the logic of the process has not changed. The scientific physician still keeps his advantage over the empiric. He studies the actual situation with keener attention; he is freer of prejudiced prepossession; he is more conscious of liability to error. Whatever the patient may have to endure from a baffling disease, he is not further handicapped by reckless medication. In the end the scientist alone draws the line accurately between the known, the partly known, and the unknown. The empiricist fares forth with an indiscriminate confidence which sharp lines do not disturb.

Flexner's description of science as a way of thinking reminds me what Carl Sagan said about only teaching the products of science and science as more than a body of knowledge, he said:

If we teach only the findings and products of science - no matter how useful and even inspiring they may be - without communicating its critical method, how can the average person possibly distinguish science from pseudoscience? Both then are presented as unsupported assertion.

Carl Sagan, The Demon-Haunted World: Science As a Candle in the Dark, 1996

The recent criticism of a prevailing belief is a service to the proponents of that belief, because if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of science is its most striking property, and sets it off from many other areas of human endeavor, such as politics and theology. The idea of science as a method rather than a body of knowledge is not widely appreciated outside of science or indeed in, I’m sorry to say, in some of the corridors inside of science. For this reason, I and some other of my colleagues in the AAAS have advocated a regular set of discussions at the annual AAAS meeting of hypotheses which are on the borderlines of science or which have attracted substantial public interest. The idea is not to attempt to definitely to settle such an issue, but to illustrate the process of reasoned disputation, and hopefully to show how scientists approach a problem which does not lend itself to crisp experimentation or is unorthodox in its interdisciplinary nature or otherwise evokes strong emotions.

There is no amount of knowledge or sense of confidence that can substitute a scientific attitude.

No comments:

Post a Comment

1. You should attempt to re-express your target’s position so clearly, vividly, and fairly that your target says, “Thanks, I wish I’d thought of putting it that way.
2. You should list any points of agreement (especially if they are not matters of general or widespread agreement).
3. You should mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Daniel Dennett, Intuition pumps and other tools for thinking.

Valid criticism is doing you a favor. - Carl Sagan