Clinical Trials and Evidence-Based Medicine
No thinking person doubts the value of properly implemented clinical trials, and every thinking physician believes in evidence-based medicine. Still, it should be noted that clinical trials are not the only way to discover the truth. Furthermore, there can be inaccuracies in the evidence used to arrive at a conclusion.
For example, the conclusions of a clinical trial depend upon the accuracy of the initial examination of a patient. Trials that deal in part or exclusively with symptoms -- including abnormalities elicited on physical examination or abnormalities discovered in the electrocardiogram or chest x-ray film -- are often subject to error, because this type of evidence may not be checked by competent investigators.
As we continue to gain more information about the benefits or lack of benefit of various treatments from carefully executed clinical trials, we must not forget 2 points:
No thinking person doubts the value of properly implemented clinical trials, and every thinking physician believes in evidence-based medicine. Still, it should be noted that clinical trials are not the only way to discover the truth. Furthermore, there can be inaccuracies in the evidence used to arrive at a conclusion.
For example, the conclusions of a clinical trial depend upon the accuracy of the initial examination of a patient. Trials that deal in part or exclusively with symptoms -- including abnormalities elicited on physical examination or abnormalities discovered in the electrocardiogram or chest x-ray film -- are often subject to error, because this type of evidence may not be checked by competent investigators.
As we continue to gain more information about the benefits or lack of benefit of various treatments from carefully executed clinical trials, we must not forget 2 points:
Clinical trials are not needed for every act we perform any more than it is necessary to measure the depth of the Grand Canyon in millimeters to determine that it is a big ditch. We do not need a clinical trial to determine the value of a new instrument that improves the determination of the ejection fraction by only a few percentage points.
The treatment of certain serious conditions cannot be submitted to clinical trials. For example, the value of surgical treatment for dissection of the proximal aorta and the value of using prophylactic antibiotics for the prevention of bacterial endocarditis cannot be tested in clinical trials.