Evidence Based Medicine
03/08/08

One would assume that medical procedures are based on sound evidence. However, this is often debatable, especially with conditions that are difficult to treat and in highly evolving disciplines such as nutrition.

There are different levels of reliability of evidence in science. The least reliable are opinions based on knowledge. As in “We think this will do some good” based on our knowledge of physiology, pharmacology, etc. No matter how well thought out a procedure is, it is only theory until it survives the scrutiny of well designed and performed testing. The highest level of evidence is generally thought to be studies that are “double blinded” with a “control” group performed on large numbers of subjects in natural settings with naturally occurring disease.

The “control group” is the group that receives no treatment or a fake treatment called the placebo. These subjects serve to compare with the treated group. “Double blinded” refers to testing where neither the subjects of the test nor the researchers know which subjects are receiving the tested treatment (and which the placebo) to prevent influencing the results in any way. Furthermore, researchers must find large numbers of subjects that have the affliction to be treated. Ideally, these subjects have obtained the affliction naturally and reside in natural settings (as apposed to laboratory settings) so as to most closely resemble subjects the procedure will eventually be used in. The larger the number of subjects in the study the better the results can be considered to be.

So called “Independent” studies are run by researchers who have no vested interest in the outcome of the study (as do drug company employed. 

True evidenced based medicine should be based on the highest quality evidence available. So, the next time you read about some great new cure, diet or treatment, stop and think like a scientist for a moment and consider the quality of the evidence. Is there really good evidence or just good marketing? When in doubt ask the appropriate professional for their opinion.