The Evidence-Based Veterinary Medicine Association (EBVMA) is continuing to try and support evidence-based medicine for veterinarians, and the latest activity in that effort is producing a series of brief, pragmatic literature reviews on common clinical problems and therapies. The first in the series is now available:
Aural Hematomas in Dogs. Prepared by Annette O’Connor, DV and Teresa Hershey, DVM. Sept., 2011
The review illustrates well the process of locating and evaluating the available evidence for a particular intervention. It found, as is all too often the case, that the evidence was not sufficient for a definitive conclusion to be made.
There are many ways that aural hematomas are treated in dogs. The articles reviewed examined hematoma drainage in combination with either oral or local injections of steroids and traditional surgical treatment. There was no evidence that adding steroids to treatment protocols reduced the number of dogs that needed to be retreated. The quality of the evidence was poor which limits any interpretation that may be made.
This is often the case in veterinary medicine, and even in human medicine. However, it is important to understand the true meaning of this outcome. It is not that any and all approaches to aural hematomas are equally likely to be useful. The application of magnets or color therapy, for example, is not justified by the fact that the evidence is not strong enough to clearly say whether or not adding a steroid to treatment improves outcomes. The fact that the evidence concerning a particular question is of limited quality and quantity means only that sweeping and definitive statements about the efficacy of particular treatments aren’t supported, not that anything anyone can dream up is reasonable.
The EBVMA is also beginning to collect other educational materials from members and make them available to the public and other veterinarians. The most recent additions include two excellent lectures by Bob Larson, a professor at the Kansas State University veterinary college.
Evidence-Based Medicine-An Introduction
Here’s my favorite slide:
Four Myths of Small Numbers and Other Biases
My favorite slide: