Evidence-based medicine: The pearls in the medical literature

Abstract

Physician assistants are continuously inundated with new pharmacologic agents, management techniques, questions from their patients, and information from the media. Primary care providers develop 2.4 questions for every 10 patient encounters1 and up to 2 questions for every 3 patient encounters;2 of these, approximately two-thirds go unanswered.2 How can PAs stay current with the medical literature, provide useful information to patients, and maintain productivity? Evidence-based medicine (EBM), a method of applying current, proven practices to patient care,1 can be used to quickly obtain information for clinical decision making. Lack of time and perceived loss of clinical judgment are two of the most common arguments against using EBM. PAs have a limited amount of time to filter through all the information that may be relevant to a patient or case. In addition, information is disseminated at a rapid rate, and a comprehensive critical analysis of an article is time-consuming.1,3 The goal is to learn to use and apply EBM rather than become an expert in the analysis process.1 Rapid-access resources and up-to-date databases help avoid the need to critically analyze every study related to a clinical question. Practice guidelines are one example of how to integrate EBM into busy practice routines.4 POEMs (patient-oriented evidence that matters) answer common clinical questions based on original research and systematic reviews and can be found relatively quickly through select databases.1JAAPA publishes POEMs in each issue. The most specific clinical questions are constructed using the PICO method.5 Questions are formulated within one of four EBM domains: harm, diagnosis, treatment, and prognosis (eg, What is the most appropriate treatment for premenopausal symptoms?). Awareness of each domain becomes more relevant when completing analyses of original literature. Step 1 Formulate a clinical question. Patient population. The clinical question needs to define the patient as specifically as possible. The search can be more refined if relevant medical history is included in the question (eg, 54-year-old perimenopausal female with hot flashes). Intervention. A new treatment method, diagnostic study, or physical examination maneuver that is being considered in the care of the patient (eg, soy protein). Comparison. An established treatment method, diagnostic study, or physical examination maneuver. In some cases, the new intervention is being compared with the standard of care (eg, does the new intervention achieve the same results as established interventions). Outcome. The question should define the desired outcome (for example, a decrease in the frequency and/or severity of hot flashes). Step 2 Search the medical literature through reputable databases. Essential Evidence Plus is a Web site that allows PAs to search for POEMs based on subject area (www.essentialevidenceplus.com). Step 3 Evaluate whether the search results are relevant to your patient and practice. Critical appraisal worksheets from the Centre for Evidence-Based Medicine are available online to help PAs who want to hone their literature-analysis skills (www.cebm.utoronto.ca/teach/materials/caworksheets). A common misconception about EBM is that it is algorithmic, limits clinical judgment, or does not account for patient variability. However, study results clearly demonstrate that EBM complements clinical experience and judgment and allows for the integration of patient values.1 The patient and his or her family should be included when integrating your analysis into the clinical decision-making process.4 Finally, evidence to support whether patients have benefitted from the integration of EBM into clinical practice is limited because EBM is not being integrated sufficiently or broadly enough to confidently assess patient outcomes.1,6 Utilizing the various EBM resources can help PAs integrate EBM into daily clinical practice (see "Table. Evidence-based medicine resources," in the online version of this article). EBM provides PAs with a valuable tool with which to answer patient-oriented questions.