Daubert, pain, evidence and inference in treating TMD.

• Jurisdiction: United States
• Author: Moses, Allen J.
• Date: 01 October 1997

In writing the majority opinion of the U.S. Supreme Court's scientific evidence ruling in Daubert v. Merrell Dow Pharmaceuticals Inc., 509 U.S. 579 (1993), Justice Blackmun explained that subjective impressions are biased by the observer's model of the world, and thus can be misleading. As such, they do not represent definitive scientific evidence or knowledge.

Pain as a scientific criterion

Take these cases:

* A dental patient complains pre-auricular pain. Examination reveals that the pain is referred from ipsilateral trigger points in sternocleidomastoid or trapezius muscles. Lidocaine injection over the temporomandibular joint results in no pain relief, but injecting the remote trigger point does relieve the pain. This is "referred pain."

* A patient complains of orofacial pain in the upper right arch, but examination reveals that it is an abscessed tooth in the lower right arch. This is "poorly localized pain."

* A patient is asked if palpation of a certain area hurts. The patient answers, "Not really." This non-definitive phrase doesn't say yes or no. We must recognize that pain is vague and quantification often is unreliable.

* If a doctor palpitates the right side of a patient's face, and the patient indicates tenderness on the left, this is an example of "psychosomatic pain." The pain exists only in the patient's mind with no known neurological circuitry, but the patient perceives it as real.

* There is no pain, but the patient is lying about pain for financial gain.

So, one must logically ask: "Based on phenomena of referred pain, poorly localized pain, vagueness of pain, unreliability of quantification, variation in perception, presence of pain, vagueness of pain, unreliability of quantification, variation in perception, presence of psychosomatic pain and people who lie about pain, how accurate can a patient's self-reports of pain be used as evidence or scientific criterion for the study of temporomandibular disorder?"

The ultimate test for separating science from non-science is the ability of science to pose testable hypotheses. Scientific hypotheses must be possible to refute. A patient's complaint of pain has no observable, testable phenomenology. A patient's subjective complaint of pain is a belief statement and as such is irrefutable, unfalsifiable and therefore unscientific as diagnostic or scientific criteria. Self-reports of a patient's pain are inherently unrestable, obviously unreliable and therefore decidedly...