May 2007

Evidence‑based practice: Where's the evidence?

by Dr. Christopher Kent

In a previous column [1], I discussed the history and definition of evidence‑based practice (EBP), and expressed concerns with how the concept has been narrowly construed by some academics and payers. The problem is not, as Sackett proposed, "Integrating individual clinical expertise and the best external evidence."[2] Every doctor does that. The problem is the cavalier dismissal of evidence that doesn't fit into a rigid hierarchy, and the compartmentalizing of the profession into two classes: 1) an oligarchy of researchers and 2) doctors who are reduced to mere technicians following the flow charts and algorithms promulgated by the elite. There is grave danger that the heart and soul of the healing encounter ‑‑ the doctor‑patient relationship ‑‑ may be a casualty of the more extreme application of this mechanistic approach.

Although there is some minor variation in evidence hierarchies, the randomized controlled trial (RCT) is usually at the top. It seems appropriate to ask the questions, "Where is the evidence to support the premise that EBP results in better clinical outcomes? Are there RCTs which demonstrate that EBP results in better, cheaper, and safer healthcare strategies?"

According to Haneline, "It should be noted that the process of EBP itself has not been rigorously tested so we do not know for sure if it actually results in improved health. No RCTs that have compared EBP with standard methods or "practice have been carried out in any of the health care professions because of the methodological difficulties and exorbitantly high costs that would be associated with attempting to execute such studies." [3]

Horn [4] posed an important question, "Why are interventions that were found to be effective in randomized controlled trials (RCTs) not associated with substantially better outcomes in actual practice?" Great question. Here are some possibilities Horn identified:

***  The complexity of the care process is not modeled adequately in RCTs.

***  Findings from homogenous RCT study samples are not applicable to all patients.

***  Inferences about individuals are based on statistics collected for groups.

Horn further noted, "Improving clinical outcomes in actual practice is complex, multidimensional, and likely much more difficult than simply using a few interventions that were found to be statistically significant in RCTs involving a single condition in a homogenous patient population...In routine practice, many combinations of patient and treatment variables affect outcomes, so a much more comprehensive approach is needed to discover how to improve quality of care."

Hunink [5] was more blunt, posing the very disturbing question, "Does evidence based medicine do more good than harm?...If we argue that medicine needs to be evidence based, then logically we need evidence to support EBM. I have yet to find that evidence." Hunink notes that EBP may not just be of questionable value ‑‑ it could be downright dangerous. "The hierarchy of evidence suggested by EBM may not be justified and can be misleading...Besides the negative effect that EBM can have on how we appraise the literature, we may waste resources through inappropriate research, especially randomised controlled trials, by blindly conforming to EBM's level of evidence."

Concerns about EBP are also being voiced in the popular press [6]. A teacher at Harvard Medical School, Jerome Groopman, writes that "medical schools have begun training students to abandon heuristics in favor of a purely stats‑based approach ‑‑ airtight algorithms, templates, prototypes, and 'decision trees' that will guide them, step by rigid step, through every conceivable interaction with a patient, like an IT technician with his list of questions." Groopman laments, "The next generation of doctors is being conditioned to function like a well‑programmed computer that operates within a strict binary framework."

Undoubtedly, such an approach is attractive to a person who was selected for admission to professional school largely for demonstrating proficiency in taking multiple choice tests and regurgitating facts. The appeal of such an approach was articulated well by Huxley [7], who wrote, "The real charm of the intellectual life ‑‑ the life devoted to erudition, to scientific research, to philosophy, to aesthetics, to criticism ‑‑ is its easiness. It's the substitution of simple intellectual schemata for the complexities of reality; of still and formal death for the bewildering movements of life."

There is an even more pernicious aspect to the appeal of EBP: The individual practitioner may feel absolved of responsibility for professional decision making. After all, if the doctor follows the "best practices" promulgated by an all‑knowing oligarchy of self‑styled "experts," there is no responsibility for a bad outcome on the part of the practitioner, who sincerely believes that the patient has received the best care possible. Never mind that given the myriad variations in human anatomy, physiology, and psychology, an alternative approach might have produced a better outcome. That would require creative thinking, skill, experience, and judgment. There is no need to subject oneself to disturbing moments of introspection when the only question asked is, "Did you follow the cookbook?" Of course, payers and hospitals love it, too. It limits their liability, and, better yet, makes doctors essentially equal and interchangeable.

Let's hope that chiropractors do not fall into the trap of equating quality with homogeneity of care. And let's not lose sight of the fact that the doctor‑patient relationship, and the ability to consider the unique needs, desires, and peculiarities of individual patients is what separates doctors from mere technicians.

References

1. Kent C: "Evidence‑based chiropractic: fad, folly, or fascism?" The Chiropractic Journal. January 2007. http://www.worldchiropracticalliance.org/tcj/2007/jan/kent.htm

2. Sackett DL, Rosenberg WMC, Gray JAM, et al: "Evidence based medicine: what it is and what it isn't." BMJ 1996;312:71‑72.

3. Haneline MT: "Evidence‑Based Chiropractic Practice." Jones and Bartlett Publishers. Sudbury, MA. 2007. Page 7.

4. Horn SD: "Performance measures and clinical outcomes." JAMA 2006;296(22):2731‑2732.

5. Hunink MGM: "Does evidence based medicine do more good than harm?" BMJ 2004;329:1051 (30 October). http://bmj.bmjjournals.com/cgi/content/full/329/7473/1051

6. Anderson S: "The Talking Cure. Review of Groopman J: How Doctors Think." New York magazine. March 26, 2007. Pages 80‑81.

7. Huxley A: "Point Counter Point." Quoted in Smith RF: "Prelude to Science." Charles Scribner's Sons. New York, NY, 1975. Page 8.

(Dr. Christopher Kent, president of the Council on Chiropractic Practice, is a 1973 graduate of Palmer College of Chiropractic. The WCA's "Chiropractic Researcher of the Year" in 1994, and recipient of that honor from the ICA in 1991, he was also named ICA "Chiropractor of the Year" in 1998. He is director of research and a co‑founder of Chiropractic Leadership Alliance. An attorney as well as a chiropractor, Dr. Kent is a member of the California bar. With Dr. Patrick Gentempo, Jr., Dr. Kent produces a monthly audio series, "On Purpose," covering current events in science, politics and philosophy of vital interest to the practicing chiropractor. For subscription information call 800‑892‑6463.)