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EMS RESEARCH Level of Evidence Designations It is important to remember that every study should be reviewed independently. The fact that it is a randomized controlled study does not ensure that its results are valid. That said, methodology does play a role in evaluating a study's importance. The American Heart Association qualifies the validity of research in a linear fashion using a "level of evidence" designation, which assigns varying levels of importance based on the way a study was conducted. This progression is useful in evaluating the importance of data and can be used as a framework for considering the utility of a particular study. • Level of Evidence 1. In this sliding scale, the highest level (most valuable) set of data would result from RCTs or metaanalyses of RCTs. • Level of Evidence 2. Studies using concurrent controls without true randomization. Because they are often retrospective and because the methods are more difcult to control without randomization, these types of studies are often less reliable. • Level of Evidence 3. Studies using retrospective controls. There is little control of these experiments, as the testing is In an age of slick marketing and everburgeoning technology, quality research and an evidence-based approach will help us answer questions and expend our resources wisely. But what about the local level—how does EMS research affect the practice of a single paramedic? Consider your state, regional or even service-level protocols. Decisions regarding scope of practice, equipment and medications are made every day. Medical directors, state officials and services consult relevant research to aid in choosing the paths and procedures that make the most sense. Consider also the dynamic nature of healthcare. The history of EMS is chock full of ideas, medications and other therapies that were considered state of the art until they were thoroughly examined and determined to be incorrect. Understanding how to interpret research will help you, as a provider, stay on the cutting edge of patient care. Even in the moment of patient care, research can be beneficial. Using based on events that have already occurred. Because of this, it is difcult to ensure similar circumstances among research subjects. Although the data from retrospective studies may be useful, they can be prone to bias. • Level of Evidence 4. Studies without a control group (e.g., case series). In these studies, only one group is looked at and is not compared to a second group. Here there is no control group against which to examine the results. Important information may be gained, but outcomes are difcult to truly understand without comparing with similar patients who received a diferent therapy. • Level of Evidence 5. Studies not directly related to the specific patient/population (e.g., a diferent patient/population, animal models, or mechanical models). These studies are common in EMS and are frequently used to evaluate prehospital treatments. Unfortunately, their data are prone to a wide range of interpretation, as we must make assumptions that what works in diferent populations or under diferent circumstances would work in the world of EMS. research to guide immediate decisions used to be the realm only of physicians, but now as paramedics learn to read and effectively interpret research, this door opens to them as well. Consider the recent discussions around the drug vasopressin. This drug may be an option for you in cardiac arrest care as a substitute for epinephrine. In the moment, you might be faced with a decision to use either drug. If you have followed the research, you might know that there has been little evidence to support its use in pediatrics, even though it might be available in that circumstance. The bottom line is that decision makers are consulting EMS research to make choices about your profession. EMS providers at every level are involved in making these decisions, but without a basic understanding of research, providers are routinely excluded from the conversation. Understanding research, even at a very simple level, allows you to speak the language of healthcare and can deliver a seat at the table. Basics of EMS Research Not all research is created equal.There are good studies and there are bad studies. As we evolve in an evidence-based environment, we should strive to embrace the best practices of conducting and evaluating research.The finer points of medical research are by no means a simple topic, and a thorough examination of how to evaluate research is beyond the scope of this text. However, some broad concepts can be helpful to consider. Remember that the process of research is the same whether you are an EMS researcher or a scientist in a laboratory. We each rely on the scientific method, developed by Galileo almost 400 years ago as a process of experimentation for answering questions and acquiring new knowledge. In this method, general observations are turned into a hypothesis (or unproven theory). Predictions are then made, and these predictions, based on the hypothesis, are then tested to either prove or disprove the theory. EMSWORLD.com | MARCH 2013 59