THE MEDICAL LITERATURE Users’ Guides to the Medical Literature XXI. Using Electronic Health Information Resources in Evidence-Based Practice

CLINICAL SCENARIO You are a general internist reviewing the condition of a 55-year-old woman with type 2 diabetes mellitus and hypertension. Her glycemic control is excellent with metformin, and she has no history of complications. To manage her hypertension, she takes a small daily dose of a thiazide diuretic. During the examination, you note that her weight is stable, she has no evidence of peripheral neuropathy, and her blood pressure is 155/88 mm Hg. After arranging for glycosylated hemoglobin, cholesterol, and microalbumin assessments, you reassure your patient that she is doing well and ask her to return in 3 months. After she has left, you notice that her blood pressure over the past 6 months has been about the same as it was today. You wonder if she would benefit from more aggressive blood pressure control. Specifically, in this patient with diabetes mellitus, would tighter blood pressure control improve survival or delay the onset of complications? You decide to find if the medical literature can help resolve the issue. Practicing evidence-based medicine involves integrating individual clinical expertise with the best available evidence from systematic research. The necessary skills include formulating a concise question that addresses uncertainties in patient management and quickly identifying the highest-quality relevant informationfromthemedical literature.Thepreviousarticles inthisseries have provided guides for the steps that follow identification of the best evidence—systematicallyassessing itsvalidityandapplicability. In thisUsers’Guide, we present an approach to choosing and subsequently searching the most efficient electronic resource for finding the best evidence. We have focused primarily on electronic resources as these are generally easier to search and more current than many print sources. However, with the relatively recent appearance of many of the resources we recommend, little research specifically addresses their relative merits. The approaches we describe reflect our experiencesandthoseofourcolleaguesworking individually or with medical trainees and encompass a wide range of learning levels.