Basics of evidence-based practice. Part 1: The nature of the evidence.

Basics of evidence-based practice are presented in 2 parts. Part 1 explores the characteristics of evidence used in evidence-based practice. Part 2 presents basic terms and processes of EBP. The nature of the evidence as the basis for clinical decisions is a major distinction between the new paradigm of evidence-based practice and yesterday's approaches to research utilization. This article discusses why research evidence is the best source of clinical knowledge, and why systematic reviews, in particular, provide the most stable knowledge for clinical practice. Sources of evidence summaries, such as Agency for Healthcare Research and Quality, are also discussed.