Effectiveness of Preanalytic Practices on Contamination and Diagnostic Accuracy of Urine Cultures: a Laboratory Medicine Best Practices Systematic Review and Meta-analysis.

BACKGROUND: Urinary tract infection (UTI) in the United States is the most common bacterial infection, and urine cultures often make up the largest portion of workload for a hospital-based microbiology laboratory. Appropriately managing the factors affecting the preanalytic phase of urine culture contributes significantly to the generation of meaningful culture results that ultimately affect patient diagnosis and management. Urine culture contamination can be reduced with proper techniques for urine collection, preservation, storage, and transport, the major factors affecting the preanalytic phase of urine culture. OBJECTIVES: The purposes of this review were to identify and evaluate preanalytic practices associated with urine specimens and to assess their impact on the accuracy of urine culture microbiology. Specific practices included collection methods for men, women, and children; preservation of urine samples in boric acid solutions; and the effect of refrigeration on stored urine. Practice efficacy and effectiveness were measured by two parameters: reduction of urine culture contamination and increased accuracy of patient diagnosis. The CDC Laboratory Medicine Best Practices (LMBP) initiative's systematic review method for assessment of quality improvement (QI) practices was employed. Results were then translated into evidence-based practice guidelines. SEARCH STRATEGY: A search of three electronic bibliographic databases (PubMed, SCOPUS, and CINAHL), as well as hand searching of bibliographies from relevant information sources, for English-language articles published between 1965 and 2014 was conducted. SELECTION CRITERIA: The search contained the following medical subject headings and key text words: urinary tract infections, UTI, urine/analysis, urine/microbiology, urinalysis, specimen handling, preservation, biological, preservation, boric acid, boric acid/borate, refrigeration, storage, time factors, transportation, transport time, time delay, time factor, timing, urine specimen collection, catheters, indwelling, urinary reservoirs, continent, urinary catheterization, intermittent urethral catheterization, clean voided, midstream, Foley, suprapubic, bacteriological techniques, and microbiological techniques. MAIN RESULTS: Both boric acid and refrigeration adequately preserved urine specimens prior to their processing for up to 24 h. Urine held at room temperature for more than 4 h showed overgrowth of both clinically significant and contaminating microorganisms. The overall strength of this body of evidence, however, was rated as low. For urine specimens collected from women, there was no difference in rates of contamination for midstream urine specimens collected with or without cleansing. The overall strength of this evidence was rated as high. The levels of diagnostic accuracy of midstream urine collection with or without cleansing were similar, although the overall strength of this evidence was rated as low. For urine specimens collected from men, there was a reduction in contamination in favor of midstream clean-catch over first-void specimen collection. The strength of this evidence was rated as high. Only one study compared midstream collection with cleansing to midstream collection without cleansing. Results showed no difference in contamination between the two methods of collection. However, imprecision was due largely to the small event size. The diagnostic accuracy of midstream urine collection from men compared to straight catheterization or suprapubic aspiration was high. However, the overall strength of this body of evidence was rated as low. For urine specimens collected from children and infants, the evidence comparing contamination rates for midstream urine collection with cleansing, midstream collection without cleansing, sterile urine bag collection, and diaper collection pointed to larger reductions in the odds of contamination in favor of midstream collection with cleansing over the other methods of collection. This body of evidence was rated as high. The accuracy of diagnosis of urinary tract infection from midstream clean-catch urine specimens, sterile urine bag specimens, or diaper specimens compared to straight catheterization or suprapubic aspiration was varied. AUTHORS' CONCLUSIONS: No recommendation for or against is made for delayed processing of urine stored at room temperature, refrigerated, or preserved in boric acid. This does not preclude the use of refrigeration or chemical preservatives in clinical practice. It does indicate, however, that more systematic studies evaluating the utility of these measures are needed. If noninvasive collection is being considered for women, midstream collection with cleansing is recommended, but no recommendation for or against is made for midstream collection without cleansing. If noninvasive collection is being considered for men, midstream collection with cleansing is recommended and collection of first-void urine is not recommended. No recommendation for or against is made for collection of midstream urine without cleansing. If noninvasive collection is being considered for children, midstream collection with cleansing is recommended and collection in sterile urine bags, from diapers, or midstream without cleansing is not recommended. Whether midstream collection with cleansing can be routinely used in place of catheterization or suprapubic aspiration is unclear. The data suggest that midstream collection with cleansing is accurate for the diagnosis of urinary tract infections in infants and children and has higher average accuracy than sterile urine bag collection (data for diaper collection were lacking); however, the overall strength of evidence was low, as multivariate modeling could not be performed, and thus no recommendation for or against can be made.

Effectiveness of practices for improving the diagnostic accuracy of Non ST Elevation Myocardial Infarction in the Emergency Department: A Laboratory Medicine Best Practices™ systematic review.

OBJECTIVES: This article is a systematic review of the effectiveness of four practices (assay selection, decision point cardiac troponin (cTn) threshold selection, serial testing, and point of care testing) for improving the diagnostic accuracy Non-ST-Segment Elevation Myocardial Infarction (NSTEMI) in the Emergency Department. DESIGN AND METHODS: The CDC-funded Laboratory Medicine Best Practices (LMBP) Initiative systematic review method for quality improvement practices was used. RESULTS: The current ACC/AHA guidelines recommend using cardiac troponin assays with a 99th percentile upper reference limit (URL) diagnostic threshold to diagnose NSTEMI. The evidence in this systematic review indicates that contemporary sensitive cTn assays meet the assay profile requirements (sensitivity, specificity, PPV, and NPV) to more accurately diagnose NSTEMI than alternate tests. Additional biomarkers did not increase diagnostic effectiveness of cTn assays. Sensitivity, specificity, and NPV were consistently high and low PPV improved with serial sampling. Evidence for use of point of care cTn testing was insufficient to make recommendation, though some evidence suggests that use may result in reduction to patient length of stay and costs. CONCLUSIONS: Based on the review of and the LMBP(TM) A-6 Method criteria, we recommend the use of cardiac troponin assays without additional biomarkers using the 99th percentile URL as the clinical diagnostic threshold for the diagnosis of NSTEMI. We recommend serial sampling with one sample at presentation and at least one additional second sample taken at least 6h later to identify a rise or fall in the troponin level. No recommendation is made either for or against the use of point of care tests. DISCLAIMER: The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention/the Agency for Toxic Substances and Disease Registry (CDC/ATSDR).

From Technical Assistants to Critical Thinkers: The Journey to World War II.

A review of professional literature was conducted to examine the history of the education of medical laboratory practitioners. This comprehensive review included historical educational milestones from the birth of medical technology to the advent of World War II. During this time period standards were developed by clinical pathologists for laboratory personnel and training programs. In addition, a formal educational model began to form and by the 1940's two years of college was required for matriculation into a medical technology program. Intertwined within the educational milestones are imprints of the evolution of critical thinking requirements and skills within the profession. For the first laboratory practitioners, critical thinking was not developed, discussed, or encouraged as duties were primarily repetitive promoting psychomotor skills.

From Technical Assistants to Critical Thinkers: From World War II to 2014.

A review of professional literature was conducted to examine the history of the education of medical laboratory practitioners. This comprehensive review included historical educational milestones from World War II to present day. During this time period the standard of two years of college required for matriculation into a medical technology program increased to four years. Critical thinking skills promoted in the educational model and applied in practice expanded from an analytic and psychomotor orientation to include those requiring extensive situational interpretation and negotiation. By the end of the twentieth century, the clinical laboratory had experienced significant scientific and technologic transformations necessitating greatly expanded roles for the medical laboratory practitioner. Though the educational requirements and education model have changed minimally since the 1970's, the knowledge and skills required for the next generation of medical laboratory practitioners continue to escalate. The second decade of the 21st century portends a transformation in medical laboratory practitioner education commensurate with the rapid advancement of science, technology, communications, and the precepts of evidence-based practice.

Autonomy and Privacy in Clinical Laboratory Science Policy and Practice.

Rapid advancements in diagnostic technologies coupled with growth in testing options and choices mandate the development of evidence-based testing algorithms linked to the care paths of the major chronic diseases and health challenges encountered most frequently. As care paths are evaluated, patient/consumers become partners in healthcare delivery. Clinical laboratory scientists find themselves firmly embedded in both quality improvement and clinical research with an urgent need to translate clinical laboratory information into knowledge required by practitioners and patient/consumers alike. To implement this patient-centered care approach in clinical laboratory science, practitioners must understand their roles in (1) protecting patient/consumer autonomy in the healthcare informed consent process and (2) assuring patient/consumer privacy and confidentiality while blending quality improvement study findings with protected health information. A literature review, describing the current ethical environment, supports a consultative role for clinical laboratory scientists in the clinical decision-making process and suggests guidance for policy and practice regarding the principle of autonomy and its associated operational characteristics: informed consent and privacy.

Capturing professionalism in pre-service education: professionalism tool development and implementation.

Recognizing that all health professions educational programs seek to graduate students possessing characteristics embodying the nebulous concept of professionalism, educators in four imaging and radiation science programs and a clinical laboratory science program collaborated to create a measurement tool for professionalism in pre-service education. The Student Professional Behavior Evaluation Tool and the process for its development and implementation are described.

Grounded theory in medical laboratory science expert practice development.

Grounded theory and methods related to expert practice development in medical laboratory science were described using data from a large national survey of medical laboratory scientists (MLS) overlaid on findings from analysis of expert practice domains reported in nursing literature. An extensive focus group/expert review iterative process followed by a survey of MLS practitioners produced 25 critical thinking (CT) behaviors important in expert practice. Factor analysis was applied to discern common threads or themes linking the CT behaviors. The 25 important CT behaviors were reduced to a 7-factor structure representing constructs underlying the individual, observable CT behaviors. This 7-factor structure in MLS was compared to the 7 practice domains identified in expert nursing practice. The comparison yielded commonality between MLS and nursing in CT behaviors observed in the 7 expert practice domains of both professions: professional techniques, caring communication, growing professionally, setting priorities, practicing with judgment, anticipating/revising, and creating unique meaning. Emergent grounded theory is that (1) critical thinking is a metaprocess that facilitates learning by interlinking the more basic processes associated with different learning orientations: cognitivist, behaviorist, humanist (affective), and situated/contextual learning, (2) CT behaviors are observable events following from the CT metaprocess, and (3) observations of CT behaviors increase as practice advances from novice to expert. Identification and definition of CT behaviors, i.e., practice competencies, along the continuum of novice to expert can serve as the foundation for MLS curriculum and instructional design as well as measurement and evaluation in both formal and continuing education settings.

Evidence based practice and advanced competencies in a MHS-CLS program.

The goals, curriculum, implementation, and immediate impacts of an entry-level Master of Health Science in Clinical Laboratory Science (MHS-CLS) degree are described as compared to the baccalaureate program (BS-CLS) in the same institution. The MHS-CLS program was instituted in fall semester, 2008; the inaugural class graduated in spring semester 2010. To document the need for the MHS-CLS, program statistics, such as the number of students entering the current BS-CLS program with previous baccalaureate degrees, numbers of students graduating with biology and chemistry degrees in the United States, CLS workforce shortages and pending retirement statistics were used. The shortage of CLS practitioners able to perform and publish evidence-based practice research also supported program need. The MHS-CLS curriculum includes advanced courses, advanced competencies incorporated into existing BS-CLS courses, and a capstone research project in evidence based practice.

A typology of evidence based practice research heuristics for clinical laboratory science curricula.

A typology of EBP research heuristics was defined relative to clinical laboratory science levels of practice. Research skills requisite for CLS baccalaureate level are associated mainly with quality control of analytic processes. Research skills at master's level are associated with pre- and post-analytic investigations, as well. Doctoral level CLS practice portends to utilize research skills facilitating quality investigations at the systems level.

The doctorate in clinical laboratory science: an executive summary.

This article describes, in informational bullets, the concept of the doctorate in clinical laboratory science. The intent of the article is to support the marketing of these new practitioners and to provide the conceptual frame and links to data for proposals required to implement educational programs for them.

Evaluating distance learning in health informatics education.

The purpose of this study was to compare academic performance between distance-learning and on-campus health informatics students. A quantitative causal-comparative research design was utilized, and academic performance was measured by final GPA scores and Registered Health Information Administrator certification exam scores. Differences in previous academic performance between the two groups were also determined by comparing overall admission GPA and math/science admission GPA. The researchers found no difference in academic performance between the two groups when final GPA scores and total certification scores were compared. However, there were statistically significant differences between the two groups in 4 of the 17 sub-domains of the certification examination, with the on-campus students scoring slightly higher than the distance students. Correlation studies were also performed, and the researchers found significant correlations between overall admission GPA, math/science admission GPA, final GPA, and certification scores.