Disclosures: 

Acknowledgments: My deep appreciation to Dr S. Nassir Ghaemi and Dr Bernard J. Carroll, for their helpful comments on this article. The views presented here, however, are my own.

** My colleague, Dr Nassir Ghaemi, has suggested that “in clinical diagnosis, the specific scientific criteria are the five [Robins and Guze] criteria of validity”; and that one cannot justifiably “separate science from validity when discussing nosology.” (personal communication, 8/29/13). (The Robins & Guze criteria (Am J Psychiatry. 1970 Jan;126(7):983-7) comprise clinical description, laboratory study, exclusion of other disorders, follow-up study, and family study—often considered the fundamental elements of “construct validity”). To be sure: “science” is intimately related to construct validity—but they are distinct concepts. “Construct validity” is essentially an outgrowth and subset of the long-established scientific method, which dates from Roger Bacon’s work in the 13th century. An empirical claim may be proved “invalid” yet be eminently “scientific.” For example, the “steady-state” theory of the universe was unquestionably grounded in the scientific method, but was eventually invalidated and replaced by the “Big Bang Theory.” By the same token, the DSM-5’s decision to eliminate the subtypes of schizophrenia (paranoid, disorganized, etc.) might someday be invalidated, based on new data—but it would be unfair, retrospectively, to call the DSM-5’s decision “unscientific.” (see Highlights of Changes from DSM-IV-TR to DSM-5, American Psychiatric Association, 2013).

^^These different aspects of the patient’s condition have been discussed in terms of “disease” (pathoanatomical entity) and “illness” (the patient’s subjective reaction) by Dr Arthur Kleinman.

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For further reading:
Pies R: DSM-5’s Validity: Non Sumus Angeli! Medscape Psychiatry. June 12, 2013 http://www.medscape.com/viewarticle/805365

Markova IS, Berrios GE: Epistemology of psychiatry. Psychopathology 2012; 45:220-227 [This paper discusses the concept that psychiatry is a “hybrid discipline” whose objects of inquiry are themselves “hybrid” constructs]