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Effect of enhanced feedback and brief educational reminder messages on laboratory test requesting in primary care: a cluster randomised trial.

BACKGROUND: Laboratory services play an important part in screening, diagnosis, and management of patients within primary care. However, unnecessary use of laboratory tests is increasing. Our aim was to assess the effect of two interventions on the number of laboratory tests requested by primary-care physicians. METHODS: We did a cluster randomised controlled trial using a 2x2 factorial design, involving 85 primary-care practices (370 family practitioners) that request all laboratory tests from one regional centre. The interventions were quarterly feedback of practice requesting rates for nine laboratory tests, enhanced with educational messages, and brief educational reminder messages added to the test result reports for nine laboratory tests. The primary outcome was the number of targeted tests requested by primary-care practices during the 12 months of the intervention. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN06490422. FINDINGS: Practices that received either or both the enhanced feedback and the reminder messages were significantly less likely than the control group to request the targeted tests in total (enhanced feedback odds ratio 0.87, 95% CI 0.81-0.94; reminder messages 0.89, 0.83-0.93). The effect of the interventions varied across the targeted tests individually, although the number of tests requested for both interventions was generally reduced. Neither intervention was consistently better than the other. INTERPRETATION: Enhanced feedback of requesting rates and brief educational reminder messages, alone and in combination, are effective strategies for reducing test requesting in primary care. Both strategies are feasible within most laboratory settings.

Clinical Laboratory Techniques↗

Efficient DNA database laboratory strategy for high through-put STR typing of reference samples.

DNA intelligence databases were installed successfully in various countries during the past few years. It is a general trend that laboratories performing STR analysis for DNA databases have to adjust to increased sample through-put, especially when dealing with a high number of reference samples. In contrast to routine forensic casework analysis, where samples of suspects and unknown samples are interpreted with regard to the specific circumstances of the case and are kept distinctly apart from other cases, DNA databases consist of single, primarily unlinked DNA profiles. Problems areas associated with the high number of anonymous DNA profiles are the risk of logistic errors, such as sample mix-up during the laboratory procedure, and the risk of typing errors during manual transcription of data and/or results. Thus, DNA databases clearly require new laboratory strategies to rise to the challenge. This paper presents an efficient automated laboratory strategy on the platform of a laboratory management information system (LIMS) with the Austrian DNA Intelligence Database as example. Two goals were tackled in particular: first, data safety by avoiding both manual interaction during critical laboratory steps (i.e. when DNA is transferred form one tube into another), and errors due to manual transcription of sample information and results. Secondly, efficient sample processing by automizing the laboratory procedure with the help of robotic instruments, thus, giving the DNA staff more time to analyze data.

Austria↗

Laboratory data and treatment outcomes of head and neck tumor patients in the elderly.

OBJECTIVE: To elicit the factors influencing the choice of treatment and the prognosis of elderly patients, we studied the clinical and laboratory data of head and neck tumor patients. The patients were divided into two groups (group A: younger than 75, group B: 75 years of age or older) and the treatment outcomes as well as the features of the laboratory data were analyzed. METHODS: The clinical records of 1350 patients (888 males, 462 females) with head and neck tumors who received their initial treatment at our hospital were reviewed. The collected data including age, the site of the primary lesion, pre-treatment health states, pre-operative laboratory results were examined. According to the treatment policy, we grouped the patients according to whether or not they had received the standard therapy for the disease and then analyzed their treatment outcomes. RESULTS: Standard therapy was not performed in 62 (5.6%) of the 1114 patients in group A and in 43 (18.2%) of the 236 patients in group B. A further analysis performed in group B (elderly patients) revealed that standard therapy was performed in 193 patients, while 43 received non-standard therapy. The prognosis for the non-standard therapy cases was poor. The averages of the laboratory test findings between groups A and B were compared, but no marked differences were observed. However, differences were observed in the ratio of patients whose data were in the normal range between group A and group B. When the laboratory data were compared between the standard and non-standard groups of the elderly, serum albumin and CBC (especially hemoglobin) showed a close relationship to the treatment modality. CONCLUSION: The ratio of patients who did not receive standard therapy was high in the age group of 75 years or older. The prognosis of patients with head and neck tumors is therefore considered to depend on whether or not a patient receives the standard therapy against the disease. The pre-treatment clinical data and the laboratory findings vary markedly among elderly patients 75 years of age or older. Regarding the treatment of head and neck tumors in the elderly, the laboratory data and clinical conditions of each individual patient should be checked carefully and every possible means should be employed in order to allow such patients to receive the standard therapy whenever possible.

Adult↗

Effect of diagnosis-related groups on diagnostic methodology in the hospital laboratory.

Traditionally physicians have ordered clinical laboratory tests for a variety of reasons. The establishment of a federally mandated prospective payment system for Medicare patients based on diagnosis-related groups has, among other things, necessitated a review of these reasons as well as the level of use of clinical laboratory services for a given diagnosis. Diagnosis-related group payment to hospitals is independent from the number of laboratory studies performed as long as the diagnosis-related group diagnosis is substantiated at the time the patient is discharged from the hospital. The cost-effective utilization of present tests as well as the adoption of new diagnostic methodologies depends on the assessment of whether a test possesses the appropriate parameters to be of sufficient diagnostic value. These factors include sensitivity, specificity, prevalence, speed, and the costs associated with false-negative or false-positive results. The assessment of the diagnostic value of present or future laboratory methods will require careful analysis relative to their financial impact both within the laboratory and for the hospital as a whole. The laboratory's knowledge of the diagnosis-related group accounting for the highest percentage of their hospital's costs, the highest volume of their cases, and the highest use of their services can aid in assessment of the appropriateness and level of laboratory services. An analysis of the percentage of microbiology costs associated with these diagnosis-related group categories for a large, tertiary care hospital is discussed.

Adolescent↗

Methicillin-resistant Staphylococcus aureus: how reliable is laboratory reporting?

Microbiology laboratories in Oregon were surveyed in 1981 to determine how often methicillin-resistant Staphylococcus aureus (MRSA) was being reported to physicians in the state. Results of this survey were surprising in three respects. First, the mean percent of S. aureus isolates reported by laboratories as methicillin-resistant was 8.3%. Second, a significant inverse correlation was found between the percent of reported MRSA and laboratory size (p = 0.0001). Finally, laboratories which retested initially resistant isolates reported significantly less MRSA (mean 3.3%, median 1%) than those laboratories which accepted initial results (mean 20%, median 12%) (p = 0.0001). Independent testing by the Centers for Disease Control of isolates reported to be MRSA confirmed that some misidentification was occurring. Participating laboratories were notified of our initial findings and their potentially serious clinical ramifications. Laboratories were resurveyed in 1982, and a significant decrease in the reported MRSA to a mean percentage of 3.4% was observed (p = 0.002). It is unlikely that this situation is unique to Oregon, and similar misreporting of MRSA to physicians in other areas of the country may be compromising the safe and effective treatment of S. aureus infections.

Health Surveys↗

Standardizing global gene expression analysis between laboratories and across platforms.

To facilitate collaborative research efforts between multi-investigator teams using DNA microarrays, we identified sources of error and data variability between laboratories and across microarray platforms, and methods to accommodate this variability. RNA expression data were generated in seven laboratories, which compared two standard RNA samples using 12 microarray platforms. At least two standard microarray types (one spotted, one commercial) were used by all laboratories. Reproducibility for most platforms within any laboratory was typically good, but reproducibility between platforms and across laboratories was generally poor. Reproducibility between laboratories increased markedly when standardized protocols were implemented for RNA labeling, hybridization, microarray processing, data acquisition and data normalization. Reproducibility was highest when analysis was based on biological themes defined by enriched Gene Ontology (GO) categories. These findings indicate that microarray results can be comparable across multiple laboratories, especially when a common platform and set of procedures are used.

Gene Expression Profiling↗

The qualitative assessment of complete dentures produced by commercial dental laboratories.

Comprehensive criteria and simple methods of assessment have been developed for the evaluation of complete dentures supplied by commercial dental laboratories. One hundred laboratories in England and Wales were selected by random sampling. A single identical complete denture case was sent from general practice addresses to each of the selected laboratories and each of the laboratory stages evaluated according to specific criteria. This paper is concerned only with the evaluation of the finished dentures. Half of the cases were treated as NHS cases and half as 'private' cases. The private cases were further subdivided into those where details were left to the laboratory and those where detailed instructions were given for all stages of denture construction. Wide variations were found in both the quality and cost of complete denture laboratory work. Evaluation of some key features of finished dentures suggests that the quality of work was superior for the private cases in which detailed instructions were given to the laboratory. Even for the private (specified) cases, however, important faults were found in a number of cases.

Communication↗

Infectious disease testing related to organ and tissue transplantation: results from a national laboratory survey.

BACKGROUND: The purpose of this national survey in the United States was to determine laboratory practices and policies related to infectious disease testing of tissue and organ donors. METHODS: Supplementary questions were asked of the laboratories that subscribe to the College of American Pathologists' 1996 Donor Center (DC-B) and Viral Markers (W1-B and W2-B) surveys. Only the laboratories that perform infectious disease testing for the purposes of organ and tissue transplantation were asked to respond to the survey. RESULTS: A total of 1563 laboratories participated in the 1996 DC-B, W1-B, and W2-B surveys. A total of 203 (13.0%) laboratories indicated that infectious disease testing was performed for purposes of tissue and organ transplantation. The majority (81. 1%) of respondents were hospital-based laboratories or regional blood centers. Variances existed in policies regarding type of testing, turnaround times, maintenance of frozen samples, confirmatory testing of positive screening tests, and the reporting of results. CONCLUSIONS: Various policies and procedures are practiced by laboratories that perform infectious disease testing related to transplantation, and standard guidelines do not currently exist. More data is needed to assess the variability of infectious disease testing of organ donors, as well as the need for standard guidelines.

Communicable Diseases↗

Elevated evolutionary rates in the laboratory strain of Saccharomyces cerevisiae.

By using the maximum likelihood method, we made a genome-wide comparison of the evolutionary rates in the lineages leading to the laboratory strain (S288c) and a wild strain (YJM789) of Saccharomyces cerevisiae and found that genes in the laboratory strain tend to evolve faster than in the wild strain. The pattern of elevated evolution suggests that relaxation of selection intensity is the dominant underlying reason, which is consistent with recurrent bottlenecks in the S. cerevisiae laboratory strain population. Supporting this conclusion are the following observations: (i) the increases in nonsynonymous evolutionary rate occur for genes in all functional categories; (ii) most of the synonymous evolutionary rate increases in S288c occur in genes with strong codon usage bias; (iii) genes under stronger negative selection have a larger increase in nonsynonymous evolutionary rate; and (iv) more genes with adaptive evolution were detected in the laboratory strain, but they do not account for the majority of the increased evolution. The present discoveries suggest that experimental and possible industrial manipulations of the laboratory strain of yeast could have had a strong effect on the genetic makeup of this model organism. Furthermore, they imply an evolution of laboratory model organisms away from their wild counterparts, questioning the relevancy of the models especially when extensive laboratory cultivation has occurred. In addition, these results shed light on the evolution of livestock and crop species that have been under human domestication for years.

Biological Evolution↗

Quality assurance growing pains: a state perspective on implementing an organizational-wide quality system in environmental laboratories.

To implement an effective and efficient quality system in a network of established environmental testing laboratories requires a committed long-term effort that is potentially fraught with multiple obstacles. This presentation discusses one state's ongoing efforts at implementing such a system. First is the need to convince management of the rationale for a quality systems-based approach versus the traditional QA/QC program. Once development of a quality system has been sanctioned, a team-based approach utilizing project planning tools is a good way to approach the effort. Resources are assigned to the development of key quality system components, and generally a phased-deployment or roll-out works best. Once implementation is underway, assuring operational utilization and compliance with the quality system are vital steps in the process. Important to successful implementation is ongoing assessment and refinement of the quality system. Fundamental and key elements of the laboratory quality system are numerous and need to work in concert with each other. Quality system elements to be discussed in the presentation range from management and QA roles and functions to the typical documentation of laboratory policies and procedures. Numerous QA assessment tools and other vital quality system practices that play an important role in making a complete quality system are addressed. In addition, efforts must be undertaken to integrate the laboratory quality system with other management systems within the organization. The bottom line is that all environmental laboratories need a quality system more now than ever. Data users need it. Customers' expectations for data quality are high. USEPA policy and/or programs call for it. Additionally, good quality systems can benefit the organization in multiple ways and help avoid the "pay-me-now or pay-me-later" syndrome. In conclusion, all environmental testing laboratories (i.e., academic, private, commercial and especially governmental) need to invest in and implement a quality system based on a recognized standard (e.g., NELAC, ISO 17025, ANSI/ASQC E-4). The author recommends pursuing NELAP laboratory accreditation with a NELAP-recognized accrediting authority.

Environmental Monitoring↗

Laboratory and analytical method performance of lead measurements in paint chips, soils, and dusts.

The National Lead Laboratory Accreditation Program (NLLAP) recognizes laboratories capable of analyzing lead in paints, soils, and dusts. NLLAP requires successful participation in the Environmental Lead Proficiency Analytical Testing (ELPAT) program. For paint chip analyses, laboratory-to-laboratory variability is about 10% relative standard deviation (RSD) for lead levels near 0.5%, the HUD definition of lead-based paint. For soil analyses, RSDs are about 9 to 10% near relevant federal soil standards and 16% near the lowest state bare soil standard that currently exists. For dust wipe analyses, RSDs range from 10 to 16% for lead levels near relevant HUD standards. Of participating laboratories, 92 to 93% consistently meet ELPAT performance limits. A variety of analytical methods gives similar results. No conclusive significant differences were found among most frequently used hotplate and microwave sample preparation techniques. In addition, several participating laboratories have successfully used ultrasonic extraction methods, a method suitable for use at abatement sites. The three most frequently used instrumental techniques, flame atomic absorption (FAA), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and graphite furnace atomic absorption show no statistically significant differences in ability to meet ELPAT performance limits. However, small statistically significant biases between these methods sometimes occur. The magnitude of biases is less than 5% of the corresponding laboratory mean near relevant federal standards except for lead levels near the lowest HUD lead wipe standard, where biases can be as high as 8%. Other instrumental methods that have been used successfully include ICP-mass spectroscopy, direct current plasma-atomic emission spectroscopy, dithizone spectrophotometry, and anodic stripping voltametry.

Accreditation↗

Task- and time-dependent weighting factors in a retrospective exposure assessment of chemical laboratory workers.

A chemical exposure assessment was conducted for a cohort mortality study of 6157 chemical laboratory workers employed between 1943 and 1998 at four Department of Energy sites in Oak Ridge, Tennessee, and Aiken, South Carolina. Previous studies of chemical laboratory workers have included members within professional societies where exposure assessment was either limited or not feasible, or chemical processing employees where laboratory and production workers were combined. Because sufficient industrial hygiene records were unavailable for all four sites, weighted duration of employment was used as a surrogate for the magnitude of exposure. Potential exposure indices were calculated for each worker using number of days employed and weighting factors for frequency of contact and year of employment. A total of 591 unique laboratory job titles indicative of a chemical laboratory worker were collapsed into 18 general job title categories. Through discussions with current and retired workers, along with examination of historical organizational charts and job descriptions, the percentage of time with activities involving the direct handling of chemicals in the laboratory was estimated for each job title category. Scaled weighting factors of 1, 0.6, 0.3, and 0.05 were assigned to the job title categories representing 100%, 60%, 30%, and 5% of daily activities handling chemicals, respectively. Based on limited industrial hygiene monitoring data, personal radiation monitoring records, and professional judgment, weighting factors that declined 4% annually were applied to each year to account for improvements in laboratory technique, advancements in instrumentation, improvement in engineering controls, and increased safety awareness through time. The study cohort was separated into three categories of chemical exposures based on department level information: (1) inorganic, (2) mixed inorganic and organic, and (3) unknown. Potential exposure indices ranged from 0.15 to 6824.5 with a median value of 377.5 and a mean equal to 884.2. This exposure assessment method is useful for epidemiologic analyses when quantitative exposure data are absent or insufficient.

Air Pollutants, Occupational↗

INR reporting in Canadian medical laboratories: an update. Thrombosis Interest Group of Canada.

A written survey of all licensed medical laboratories performing coagulation testing in Canada was undertaken in 1996 as a follow-up to a study performed in 1992. The an overall response rate was 77.4% of the laboratories surveyed. During the 4-year period between surveys, the percentage of responding laboratories using some format for international normalized ratio (INR) reporting increased from 57% to 98%. The mean International Sensitivity Index (ISI) of the various thromboplastins used had decreased from 2.07 to 1.63. However, only 35% of responding laboratories used a thromboplastin with an ISI of 1.2 or less as recommended by the American College of Chest Physicians. In 92% of cases, the ISI was said to be specified for the type of instrument, ie, optical density vs mechanical. However, in only 52% of cases was the ISI known to be specific for the particular reagent-analyzer combination used in the individual laboratory. Nine percent of the laboratories were still using an inappropriate denominator for the INR calculation. While 87% of laboratories quoted a therapeutic INR range of 2.0 to 3.0 for venous thromboembolism, there was much greater variation in the range reported for patients undergoing heart valve replacement. The situation in Canada has improved in using the INR system for prothrombin time reporting. However, additional education is required, as is greater use of thromboplastins with a lower ISI.

Animals↗

Salmonella typhi: the laboratory as a reservoir of infection.

As a part of educational and proficiency exercises thousands of students and laboratory personnel have been exposed to Salmonella typhi. In a retrospective study 24 cases of laboratory-acquired typhoid fever in the United states during a 33-month period were identified; laboratory-acquired cases represented only 2.4% of all typhoid cases but 11.2% of the sporadic cases. Twenty-one of the 24 cases occurred when S. typhi was voluntarily introduced into the laboratory for educational proficiency testing or research purposes. Twelve patients were exposed to S. typhi when working with it as an unknown organism; another five were merely present in the laboratory. Obvious breaks in technique were found to be the cause of infection for only seven of the 24 patients, although infection of the others implies that breaks in technique occurred. Laboratory-acquired typhoid fever may severe as a marker for other less severe laboratory-acquired infections; these data suggest that such infections could be common.

Adult↗

Using Q-Probes to improve the quality of laboratory medicine: a quality improvement program of the College of American Pathologists.

This paper will review the reasons for the increasing emphasis on quality assurance in American healthcare and laboratory medicine. This emphasis is driven in part by economic, social and regulatory concerns as well as the traditional commitment to the search for excellence in services provided to patients. The Q-Probes Program of the College of American Pathologists (CAP) represents a response to these pressures and will be described in some detail. The program is based upon the historical success of interlaboratory comparison programs developed and sponsored by the CAP in achieving demonstrable improvement in laboratory performance. These programs are dependent on the gathering of data from large numbers of laboratories in order to establish provisional "benchmarks" of quality practice which serve as a baseline for systematic quality improvement efforts. The Q-Probes Program gathers peer-group specific institutional data concerning defined aspects of quality practice in pathology and laboratory medicine. These highly structured programs provide laboratories and pathology services with a format to collect data for submission to the CAP for analysis and to compare their performance against that of appropriately stratified peer groups. Several representative examples chosen from clinical laboratory medicine and pathology will be presented. We will attempt to demonstrate how individual laboratory and pathology services utilize aggregate data to effect specific changes in practice that lead to improvement in processes of patient care and better patient outcomes.

Blood Specimen Collection↗

Supervised versus independent student laboratories.

The purpose of this study was to determine if classroom laboratory time could be reduced in a basic physical agents course. Fifty-seven junior physical therapy students were randomly assigned to three laboratory sections. All students received identical lectures, demonstrations, course materials, and laboratory manuals. The control group, Section 1, received supervision and assistance during laboratory practice. Students in Section 2 and Section 3 worked independent of instructor supervision but could receive assistance from the instructor in an adjacent room. Students in Section 2 were provided with feedback following periodic assessment by the instructor. Attitudinal questionnaire responses indicated that the students preferred the supervised laboratory section. The presence of the instructor during classroom laboratory practice of basic physical agents did not affect student performance. Comparison of written and practical examination results indicated no significant differences in student performance. Classroom laboratory time for faculty and students was reduced when students worked independently.

Curriculum↗

Acute care/blood gas laboratories: profile of current operations.

A survey of acute care/blood gas laboratories was conducted through the memberships of the Society of Critical Care Medicine ( SCCM ) and the National Association of Medical Directors of Respiratory Care ( NAMDRC ). Data were obtained from 227 laboratories and analyzed for operational characteristics, personnel, analyses performed, and quality assurance procedures. Analyses included blood gases/pH, saturation, P50, oxygen content, hematocrit/hemoglobin concentration, as well as sodium, potassium, calcium, osmometry, and glucose. Application of appropriate quality control was uneven in terms of types and frequencies of procedures. Education of laboratory personnel ranged from high school to graduate degrees, with the greatest numbers having associate-level and baccalaureate-level educations . Certification of laboratory personnel primarily was through the National Board for Respiratory Therapy, although 36% of the personnel had no certification or registration. Aspects of the acute care laboratory identified as needing improvement are educational and certification requirements for laboratory personnel and application of quality control procedures. The database developed from this survey will serve for ongoing assimilation of information related to the operation of acute care laboratories.

Allied Health Personnel↗

A successful experiment to reduce unnecessary laboratory use in a community hospital.

A series of interventions at a 228-bed general hospital provided physicians with feedback at regular intervals concerning the amount of laboratory services employed in treating their patients. Case-mix-adjusted estimates of laboratory tests allowed each physician to compare use of laboratory tests with that of peers in the same department at the same hospital. Physicians with "excess" practice patterns ordered hundreds more laboratory tests than average each year. A multifaceted educational program included the following: 1) meetings were held concerning costs and unnecessary laboratory tests; 2) physicians were given descriptions of their practice patterns relative to their peers as part of both large and small departmental discussions; 3) the feedback was repeated a year later; 4) a consensus conference established guidelines for test ordering; and 5) a sample of patient records was examined for appropriateness of laboratory test ordering. A total of 37% of a sample of tests ordered during the baseline period by physicians with "excess" practice patterns was classified as inappropriate. The intervention resulted in a reduction of 1.8 tests per patient (P = 0.0005). Eight of the nine tests individually showed reductions in use. Charge data from the target hospital showed a statistically significant reduction in laboratory charges per patient in the quarter following program initiation (P = 0.02) and no evidence for change in a group of five comparison hospitals. There was no evidence for reductions in the ordering of essential tests. These results demonstrate a cost-effective approach to reducing unnecessary costs that can be implemented in hospitals with integrated data systems.

Clinical Laboratory Techniques↗