Can Psychiatry be Both A Medical Science and A Healing Art? The Case for Polythetic Pluralism
Can Psychiatry be Both A Medical Science and A Healing Art? The Case for Polythetic Pluralism
“Not everything that can be counted counts; and not everything that counts can be counted.” —Albert Einstein
“The practice of medicine is an art, not a trade; a calling, not a business; a calling in which your heart will be exercised equally with your head.” —William Osler
When I was a first-year resident, a revered supervisor of mine made the statement—half-facetiously—that “in psychiatry, you can do biology in the morning and theology in the afternoon!” That remarkable claim not only intrigued and inspired me—it also became a kind of North Star in my own professional orientation, for the next 30 years. But amidst the intense and sometimes internecine conflicts that rage around and within psychiatry today, I think it is time to reexamine my supervisor’s observation. At the very least, it may be useful to use it as a kind of lens, through which recent arguments about psychiatry may be viewed.
The dilemma faced by the psychiatric profession may be epitomized in 2 e-mails I recently received, both from very well-respected, senior psychiatrists. Senior Clinician #1 is well known in the area of mood disorder classification and in applying the “medical model” and biological subtyping to various forms of major depression. He wrote me in reference to my recent essay “Misunderstanding Psychiatry . . . ,” in which I disputed the claim that psychiatric diagnosis does not make use of objective “signs,” as in general medicine.1 He opined that “. . . psychiatry has rejected the medical model of diagnosis in medical practice” and that the DSM system merely “. . . looks at the list of symptoms and their duration, rejecting [physical and laboratory] examination verifying tests and the validation of treatment responses.”
Senior Clinician #2 argued nearly the opposite point of view, opining that psychiatric residents these days are “. . . being inadequately educated, with an emphasis on . . . [a materialistic] or . . . so-called medical model.” Senior Clinician #2 represents an existential-humanistic approach to psychiatry that seeks to understand the whole person in the context of his or her environment. For him, psychiatry is primarily a “healing art,” not a branch of neuroscience. He argued that psychiatry needs to recognize and realize its true nature “. . . before the field becomes unnecessary and obsolete.”
Can both these respected clinicians be right? Has psychiatry really abandoned the “medical model” (whatever that means)? Does the present DSM framework enshrine or ignore this so-called medical model? Has psychiatry become too focused on neuroscience and “materialist” (usually termed “physicalist”) models of psychopathology, to the detriment of holistic understanding of the person? Or is the real problem our abandonment of the biomedical model in favor of a kind of promiscuous eclecticism? Can our profession ever hope to overcome all these antinomies and develop an Einsteinian, “unified field theory” of psychiatric illness? How might such a unified theory partake of both “biology” and “theology,” to return to my supervisor’s observation? Obviously, this essay can do no more than sketch some very tentative answers to these questions—but here goes.
First of all, what do psychiatrists and other physicians mean by the “medical model”—also called, the “biomedical model”?
Mosby’s Medical Dictionary (8th ed) defines the “medical model” as
“. . . the traditional approach to the diagnosis and treatment of illness as practiced by physicians in the Western world since the time of Koch and Pasteur. The physician focuses on the defect, or dysfunction, within the patient, using a problem-solving approach. The medical history, physical examination, and diagnostic tests provide the basis for the identification and treatment of a specific illness. The medical model is thus focused on the physical and biologic aspects of specific diseases and conditions.” 2
In this sense, the last two DSMs can hardly be seen as exemplars or instantiations of “the medical model.” As McHugh and Slavney3 point out, DSM-III was primarily interested in enhancing diagnostic reliability—essentially, agreement on diagnosis among observers—and not in establishing the biological validity of any condition. Nor have biological factors been a central (or even a peripheral) part of DSM criteria from DSM-III to the expected DSM-5. So it would be wrong to characterize the DSMs as exemplars of “the medical model” or of “biological psychiatry,” as many commentators often claim. Notice, by the way, that there is nothing inherent in this dictionary definition of the medical model that precludes careful attention to the patient’s verbal account of what is wrong, or that “encourages a view of the patient as a machine.”4 These misattributions become important when we consider Dr Nicolas Kontos’s5 argument, below, concerning the “biomedical Straw Man.”
Rather remarkably, Mosby’s Medical Dictionary goes on to note that
“Nursing differs from the medical model in that the patient is perceived primarily as a person relating to the environment holistically; nursing care is formulated on the basis of a holistic nursing assessment of all dimensions of the person (physical, emotional, mental, and spiritual) that assumes multiple causes for the problems experienced by the patient. Nursing care then focuses on all dimensions, not just physical.”2
This is actually an extraordinary statement, and I’ll come back to it when I introduce the concept of “polythetic pluralism”—but on its face, this description of the “nursing model” ought to give every physician pause, particularly psychiatric physicians. Another reason to reconsider the “medical model” is the politico-rhetorical “baggage” this term has acquired in recent decades, as public disenchantment with medical diagnosis—and particularly, psychiatric diagnosis—has grown. Consider this claim from a UK Web site, advocating for the disabled:
“Under the medical model, disabled people are defined by their illness or medical condition. They are disempowered: medical diagnoses are used to regulate and control access to social benefits, housing, education, leisure and employment.”6
“Straw Man” or not, similar claims about the medical model have been voiced by various advocacy groups—and many psychiatrists—highly critical of psychiatric diagnosis and practice. These critics usually use the term “reductionistic” in speaking of the medical model, with the implication that ordinary emotions and “problems in living” are being increasingly and inappropriately “medicalized.”7
Yet it was the psychoanalyst and internist, Dr George Engel,8 who most prominently called attention to the reductionist nature of the traditional medical model, and who called for a new approach—one that would “. . . include the psychosocial without sacrificing the enormous advantages of the biomedical approach.” It should also be noted that “reductionism” in psychiatry is not confined to those who advocate either a DSM-categorical approach or a strictly biomedical approach. As Dr Glen Gabbard9 has observed, “Both [psychoanalysts] and their patients secretly are drawn to simple formulations that eschew complexity.” Reductionism, in short, is an equal-opportunity habit of mind.
To be sure, Engel’s biopsychosocial model (BPSM) has come in for pointed criticism in recent years. Some, like Dr Nassir Ghaemi,10 have argued that the BPSM has led to a sort of mishmash of treatment approaches, in which the psychiatrist adds “a little of this and a little of that” (my phrase, not Ghaemi’s) to the treatment mix, without basing the decision on rigorous evidence. And, in a thoughtful critique, Kontos has argued that Engel himself created a kind of “Straw Man,” by mischaracterizing the biomedical model, eg, as one that effectively discourages dialogue with the patient and “encourages a view of the patient as a machine.” Kontos5 persuasively argues that promulgation of this “Straw Man” model has led to the misperception that “. . . most physicians are purposefully complicit in efforts to promote inadequate patient care.” Indeed, this is a charge often leveled against psychiatrists who supposedly adhere to this bowdlerized version of the medical model.
A complete discussion of the BPSM is beyond the scope of this essay. Nevertheless—while acknowledging both deficiencies in and misrepresentations of the model—the BPSM at least represented an attempt to move psychiatry toward a humane and holistic approach to the patient. It seems to me that Engel must be given substantial credit for this, regardless of his own mischaracterizations of biomedicine or the misapplication of the BPSM by some clinicians.
I have already noted that the DSM framework does not exemplify the medical model as defined above. Ironically, the DSM approach manages to achieve the “worst of both worlds”: it does not adhere to a robust form of the biomedical model, but neither does it provide a rich, coherent existential-phenomenological basis for understanding the patient’s psychology. There are very few diagnostic criteria in DSM that help explain anything important about the inner world of the emotionally disturbed individual. (For a sense of what I mean, I recommend Silvano Arieti’s11 magisterial description of the inner world of the patient with schizophrenia.)