Preamble: 'evidence in action: the Laboratory Medicine Best Practice initiative'.

The purpose of this special section is to present findings from evidence-based systematic reviews conducted as part of the Laboratory Medicine Best Practices (LMBP) initiative from the United States Centers for Disease Control and Prevention (CDC) Division of Laboratory Science and Standards (DLSS). The systematic reviews comprising this special section examine various practices utilized by the clinical laboratory to provide information for care of patients. The term ‘practices’ as used in these reports represents protocols, procedures, policies, techniques, processes, systems, standards, incentives, activities, and interventions that are used to provide healthcare to patients. These systematic reviews are intended to address timely and pragmatic issues that are encountered frequently in the Laboratory Medicine environment. Laboratory practices in diverse topics are examined that include: use of barcoding for reducing patient specimen and test identification errors, reducing blood culture contamination in in‐patient settings, timely critical value reporting in in‐patient settings and blood collection techniques to reduce the rates of hemolysis in blood samples from the emergency department. The selection of topics for these and future best practice systematic reviews was guided, in part, by the Institute of Medicine (IOM) ‘Crossing the Quality Chasm’ report, which states that healthcare should be safe, timely, efficient, effective, equitable and patient centered to achieve substantial improvements in the quality of health care. Regarding patient safety specifically, it has been stated that nearly 100,000 deaths annually are attributable to medical error [1–3]; this information has prompted an increased emphasis on patient safety and quality improvement in medicine over the past decade, including in the specialty of Laboratory Medicine. The IOM Roundtable on Quality of Care classified threats to healthcare quality into three broad categories: overuse (receiving treatment of no value), underuse (failing to receive needed treatment), and misuse (errors and defects in treatment) [4]. Laboratory medicine testing can be viewed as consisting of three phases: preanalytical, analytical and postanalytical [5]. It has been established that most errors occur in the preanalytical and postanalytical testing phases [6–9]. For this reason laboratory practices in these phases are emphasized in the LMBP systematic reviews presented in this special section. Fundamental principles for the LMBP systematic reviews include transparency, scientifically sound information, and fostering an inclusive process open to all relevant stakeholders and to the public. The LMBP review process methods are designed so that given the same evidence, the review findings can be replicated by an entirely different review team. To be effective, the reviews must be completed and disseminated in a timely fashion as the recommendations must be applied in practice while they are relevant. Work on LMBPs is accomplished in active collaboration with stakeholders representing germane specialties, professional societies and guideline-developing organizations. Collaborators and participating stakeholders have a