Wednesday, May 16, 2007

Beyond the Illusion

Natural variations of disease:
Phenomena often mistaken for medical treatment success

Understanding the natural history of disease sheds a light on how well a given treatment is really working. This is an area where many people, professional health practitioners or not, often get tripped up by erroneously attributing improvements in a disease to whatever treatment is being used. Elaborating a little on the "Chasing Placebo's" post, I'd like to touch on some specific phenomena that are easily confused for treatment successes in medicine and especially alternative medicine.

Spontaneous improvement
As simple as this sounds, it is common for diseases to completely or temporarily improve through a variety of natural processes. A virus "burns itself out" or a failing organ reaches a plateau and begins to work reasonably well. The body has thousands of possible solutions to reach for when confronted with pathology, many times it attains good results with little outside help.

Regression to the mean
Many diseases, especially chronic and slowly progressive ones tend to have a waxing and waning behavior. This is the classical good day/bad day scenario often observed by the medical world. Reading too much into our efforts can lead to inappropriate assumptions. "Post hoc, ergo propter hoc" or "after this, therefore because of this" is a very common fallacy associated with this natural cyclic behavior of many diseases. I treated with x, and the patient improved, therefore it was because of x treatment.

Hawthorne effect
This is a perceived improvement following a treatment. It has to do with psychosomatic influences related to illusory cognitive perceptions. The term originates from a 1924 experiment at the Hawthorne General Electric plant where employees were told that the lighting levels would be manipulated to study their effect on production. Whether the lighting increased or decreased production seemed to increase.

Additional treatment
This is a very common fallacious association. Many alternative practices are implemented along with other evidence based approaches, but any positive response is associated predominantly with the alternative therapy. "Coincidence does not equal certainty" as Michael Shermer noted.

"Doc, ever since I started taking Sammy to the acupuncturist he started walking so much better! By the way, I need more of those arthritis pills, without them he can't move..." This makes me want to hit my head against a wall, but amazingly, it is a very common scene at the hospital.

Conditioning and Expectancy
This is another perceptual illusion, and can be the basis for supposed improvements in some animals. It is a form of learning an training where a conditioned response can be confused with some type of improvement in a chronic disease. "Spot perks up every time after seeing you..." could be nothing more than a change in that persons or animals routine.

Perception of the client and Practitioner profiles
How a disease affects a persons well being can be influenced implementing simple social interactions. By listening, touching, and spending focused time on a patient, they may be better able to confront the challenges of that disease.

This is a delicate subject because the health provider needs to walk a fine line between inadvertently creating false hope, and setting realistic goals. If you have a ready response for everything-"Well, if this doesn't work, we'll do this other thing"-something positive might fall into your lap. However, the risk of creating "delusional" illusions and, consciously or not, falling into deceptive practices seems alarmingly high.

Why People believe Weird Things. Shermer, M. Henry Holt & Co. New York. 2002
Complementary and Alternative medicine Considered. Ramey, D, Rollins,B.
Blackwell Pub. Iowa. 2004

No comments: