The amount of available literature (evidence) is relatively small in veterinary medicine, so searching for and locating the proper information is challenging. Once you find plausible information, it is vital to evaluate it based on whether the science itself is valid, and based on real life experiences of your own and of your colleagues. As simple as that may sound, there are more factors that go into finding and evaluating solid evidence than one may think. A 2009 article written by Stanley Robertson, DVM has useful insights on this topic.