October 01, 2002

James H. Nichols, Ph.D., DABCC, FACB

“Evidence-based medicine is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients.”—Sackett, et al. Brit Med J 1996;312:71–2.
The practice of evidence-based medicine (EBM) means integrating clinical expertise with the best available external clinical evidence from systematic research. The process of developing recommendations for effective EBM, however, is much more difficult than providing a neat and tidy explanation for such a multifaceted concept. An effective strategy for practicing EBM can be broken down into five key competencies: asking answerable clinical questions; translating them into effective searches for the best evidence; critically appraising that evidence for its quality, validity and importance; integrating the best evidence into effective testing and treatment options that consider patients’ values and preferences; and evaluating and improving the performance of EBM-driven clinical practice.

The goal of EBM is to develop pathways of care and guidelines for achieving optimal patient outcomes based on existing evidence. By blending research evidence with clinical experience, EBM indicates the most cost-effective manner for treating the average patient with a specific condition in order to obtain the best health outcome, but does not dictate patient management nor does it tell physicians how to practice medicine.

In the case of laboratory testing as it relates to patient diagnosis, EBM means determining whether evidence on the accuracy of a given diagnostic test is valid, whether the test has been demonstrated to accurately distinguish patients with and without the disorder, and whether that test should be applied to a specific patient. With the rapid emergence of relatively new and untried testing technologies—including several in the realm of point-of-care testing (POCT)—EBM is becoming an increasingly significant consideration in lab testing. In the last decade, POCT technologies have materialized as a response to institutional pressures for faster delivery of laboratory results. While the medical community now recognizes that POCT should not be utilized as a core lab replacement in all patient populations haphazardly without consideration of the test limitations and evaluation of a faster result on patient care, the peer-reviewed data needed to evaluate these devices remains sparse. The National Academy of Clinical Biochemistry has recently launched an effort to develop recommendations for evidence-based “best” practice of POCT. For more information on this project, go to www.nacb.org.