Guidelines for developing and testing clinical decision rules.

Clinical decision rules (CDRs) are decision support tools that synthesize evidence for use in bedside practice. They differ from other decision support tools in the methodological rigor with which they are developed. This article describes the important considerations in developing a CDR, including identifying the need for the rule, carefully defining the outcome variable, identifying and selecting the possible predictor variables, and guidelines for initial testing of the CDR. The process of developing and testing CDRs is best undertaken by teams of researchers, with clinical nurses providing important input in both the development and testing. It's important that clinical nurses understand both the contributions of CDRs and their inherent limitations, as appropriate use of well-developed, well-validated CDRs will become more and more a necessity in evidence-based nursing.