Evidence-based medicine: useful tools for decision making.

Evidence-based medicine (EBM) integrates clinical experience and patient values with the best available research information. There are four steps in incorporating the best available research evidence in decision making: asking answerable questions; accessing the best information; appraising the information for validity and relevance; and applying the information to patient care. Applying EBM to individual patients requires drawing up a balance sheet of benefits and harms based on research and individual patient data. The most realistic and efficient use of EBM by clinicians at the point of care involves accessing and applying valid and relevant summaries of research evidence (evidence-based guidelines and systematic reviews). The future holds promise for improved primary research, better EBM summaries, greater access to these summaries, and better implementation systems for evidence-based practice. Computer-assisted decision support tools for clinicians facilitate integration of individual patient data with the best available research data.