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Solvent use and time to pregnancy among female personnel in biomedical laboratories in Sweden.

OBJECTIVES: To elucidate possible effects on fecundability from chemical, biological, and physical agents in laboratories, a retrospective study based on a questionnaire was conducted among female personnel who worked in Swedish biomedical research laboratories. Female personnel in non-laboratory departments were used as a reference group. The maximum number of women included in the analyses was 560. This corresponded to 2519 menstrual cycles. These women had given birth at least once during the period 1990-4. METHODS: Time to pregnancy was used to estimate the fecundability-that is, probability of conception of a clinically detectable pregnancy per cycle. The fecundability ratio (FR) between exposed and unexposed cycles was calculated with a discrete time analogue of the Cox's proportional-hazards model. The FR estimates below unity indicate subfecundity. RESULTS: Work with organic solvents in general in laboratory work, gave a decreased adjusted fecundability ratio (FR) of 0.79 (95% confidence interval (95 % CI) 0.68 to 0.93). Moreover, work with acetone and use of viruses also showed decreased FRs, 0.72 (0.53 to 0.97) and 0.66 (0.49 to 0.90), respectively. CONCLUSIONS: The results of the present study give some indications of reduced fecundability for work with specific agents in laboratories, and support previously reported findings of a negative influence of organic solvents on fecundity among female laboratory personnel.

Adult↗

Lung function decline in laboratory animal workers: the role of sensitisation and exposure.

BACKGROUND: Little is known about the relation between allergic sensitisation and subsequent long term lung function changes in working populations exposed to sensitising agents. AIMS: To investigate whether exposure and work related sensitisation to laboratory animals are associated with lung function decline. METHODS: The relation between exposure and sensitisation to laboratory animal allergens and changes in lung function was investigated in a longitudinal study (median follow up 2.0 years) among 319 laboratory animal workers. Subjects who had been working with laboratory animals for less than 4 years (n = 102) were analysed separately, since an earlier cross sectional analysis had suggested a strong healthy worker effect in more experienced workers. RESULTS: In multiple regression analyses both sensitisation and exposure appeared to contribute independently to lung function decline in subjects who had been working with laboratory animals for less than 4 years, adjusting for gender, age, smoking, and atopy. Lung function decline was most pronounced in sensitised subjects who continued to be in contact with the animals to which they were sensitised, with estimated average excess declines in FEV1, FVC, and MMEF of 83 ml/y (p < 0.05), 148 ml/y (p < 0.01), and 7 ml/s/y (p = 0.9). CONCLUSIONS: We conclude that exposure to laboratory animals is a significant risk factor for accelerated lung function decline, and that sensitised workers are especially at risk.

Adult↗

Feedback of laboratory usage and cost data to clinicians: does it alter requesting behaviour?

In a 1 year prospective study we evaluated the effect of feedback of laboratory data on the requesting behaviour of physicians in general medicine. Data on within-hours and out-of-hours clinical chemistry laboratory usage and revenue expenditure for inpatients and outpatients, expressed in terms of clinical workload, were supplied monthly to a group of three consultant physicians in general medicine. With these data the physician could monitor his performance over a period of time and compare it with that of his peers. Two consultants in general medicine who received no information served as controls. Over a period of 6 months, there was a 25%, 13% and 18% decrease in tests (P less than 0.01), requests (P less than 0.05) and revenue expenditure (P less than 0.01) per outpatient visit, respectively, in the intervention group of physicians following the introduction of feedback when compared to their baseline period and to the control group. The decrease (P less than 0.01) was in the commonly requested and 'seemingly cheap' tests. There was no significant change in laboratory use and expenditure on inpatients. The feedback of laboratory data was acceptable to the physicians, raised their awareness of laboratory usage and costs and decreased laboratory workload and expenditure.

Feedback↗

A comparative study of six commercial lipoprotein(a) assays in seventeen laboratories within the British Isles.

Seventeen laboratories in the British Isles participated in a study to compare six different commercially available immunoassays for serum lipoprotein(a) (Lp(a)) and to establish reasons for the variations in the measurement of serum Lp(a) concentrations. Pooled serum was distributed neat and after dilution at a central laboratory. In addition, the central laboratory sent unpooled serum sampled monthly from six healthy volunteers to each of the participating laboratories for 12 months. The assays all gave linear dilution curves which were parallel, although the reported values varied twofold. There were major differences in the values assigned to different manufacturers' calibrants which was not explained by whether the units employed were whole Lp(a), the protein moiety of Lp(a) or simply apolipoprotein(a). The coefficient of variation for the reported value of Lp(a) over 12 months was 33%. The component variation was 10% after adjustment for inter-laboratory and intra-laboratory variation. Some individuals clearly had a greater tendency to variable serum Lp(a) concentrations than others, but all the assays responded to this in the same way. Thus, the assays tested probably measured the same analyte. The problem of calibration could largely be addressed if agreement were reached by the manufacturers. Even with improvements in analytical precision it should be realized that multiple measurements of serum Lp(a) levels are necessary if the true mean value is to be appreciated. Individuals showing wide variation in serum Lp(a) may reward further study if its role is to be established.

Clinical Laboratory Techniques↗

The importance of laboratory data for comparing outcomes and detecting 'outlier' wards in the treatment of patients with pneumonia.

OBJECTIVES: To evaluate whether routine laboratory data can improve the ability to compare risk-adjusted outcomes of different medical wards, and to detect 'outlier' wards with significantly better or worse outcome. METHODS: Patient data were taken from the Combined Patient Database Systematic Management and Research Tool, a database created by merging different computerized sources at a tertiary care hospital. All patients admitted to internal wards with the diagnosis of pneumonia during the years 1991-1995 were included (n = 2734). The outcome variable was mortality 30 days post-admission. We used three comorbidity measures based on ICD-9-CM codes as possible predictors of mortality: secondary diagnoses; the Health Care Financing Administration severity index; and the Charlson comorbidity index. Models were created using logistic regression. To each model, laboratory data gathered in the first 48 hours after admission were added. To identify 'outlier' services we determined whether the patients' ward was an independent predictor of mortality. The area under the receiver operator curve (ROC) of the models was used for comparisons. RESULTS: The area under the ROC was 0.65-0.72 for the models based on age and comorbid diagnoses. The addition of laboratory data improved markedly the discriminatory ability of each of the models, as reflected by an increase in the area under the ROC to 0.83-0.84. An 'outlier' ward with a higher risk-adjusted mortality rate was identified only by the models that included laboratory data. CONCLUSION: Basic, automated, routinely gathered laboratory data added significantly to the discriminatory power of risk models based on administrative data with abstracted diagnoses. Addition of laboratory data improved the ability to identify providers with possible exceptional quality of care.

Age Factors↗

Correlation of same-visit HbA1c test with laboratory-based measurements: a MetroNet study.

BACKGROUND: Glycated hemoglobin (HbA1c) results vary by analytical method. Use of same-visit HbA1c testing methodology holds the promise of more efficient patient care, and improved diabetes management. Our objective was to test the feasibility of introducing a same-visit HbA1c methodology into busy family practice centers (FPC) and to calculate the correlation between the same-visit HbA1c test and the laboratory method that the clinical site was currently using for HbA1c testing. METHODS: Consecutive diabetic patients 18 years of age and older having blood samples drawn for routine laboratory analysis of HbA1c were asked to provide a capillary blood sample for same-visit testing with the BIO-RAD Micromat II. We compared the results of the same-visit test to three different laboratory methods (one FPC used two different laboratories). RESULTS: 147 paired samples were available for analysis (73 from one FPC; 74 from the other). The Pearson correlation of Micromat II and ion-exchange HPLC was 0.713 (p < 0.001). The Micromat II mean HbA1c was 6.91%, which was lower than the 7.23% from the ion-exchange HPLC analysis (p < 0.001). The correlation of Micromat II with boronate-affinity HPLC was 0.773 (p < 0.001); Micromat II mean HbA1c 6.44%, boronate-affinity HPLC mean 7.71% (p < 0.001). Correlation coefficient for Micromat II and immuno-turbidimetric analysis was 0.927 (p < 0.001); Micromat II mean HbA1c was 7.15% and mean HbA1c from the immuno-turbidimetric analysis was 7.99% (p = 0.002). Medical staff found the same-visit measurement difficult to perform due to the amount of dedicated time required for the test. CONCLUSION: For each of the laboratory methods, the correlation coefficient was lower than the 0.96 reported by the manufacturer. This might be due to variability introduced by the multiple users of the Micromat II machine. The mean HbA1c results were also consistently lower than those obtained from laboratory analysis. Additionally, the amount of dedicated time required to perform the assay may limit its usefulness in a busy clinical practice. Before introducing a same-visit HbA1c methodology, clinicians should compare the rapid results to their current method of analysis.

Adolescent↗

Frequency of laboratory test utilization in the intensive care unit and its implications for large-scale data collection efforts.

OBJECTIVE: Mapping local use names to standardized nomenclatures such as LOINC (Logical Observation Identifiers Names and Codes) is a time-consuming task when done retrospectively or during the configuration of new information systems. The author sought to identify a subset of intensive care unit (ICU) laboratory tests, which, because of their frequency of use, should be the focus of efforts to standardize test names in ICU information systems. DESIGN: The author reviewed the ordering practices in medical, surgical, and pediatric ICUs within a large university teaching hospital to identify the subset of laboratory tests that represented the majority of tests performed in these settings. The author compared the results of his findings with the laboratory tests required to complete several of the most frequently used ICU acuity scoring systems. RESULTS: It was found that between 104 and 202 tests and profiles represented 99% of all testing in the three ICUs. All the laboratory studies needed for six commonly used ICU scoring systems fell into the top 21 laboratory studies and profiles performed in each ICU. CONCLUSION: The author identified a small subset of the LOINC database that should be the focus of efforts to standardize test names in ICU information systems. Mapping this subset of laboratory tests and profiles to LOINC vocabulary will simplify the process of collecting data for large-scale databases such as ICU scoring systems and the configuration of new ICU information systems.

APACHE↗

A survey of laboratory practice in the clinical authorization and reporting of results.

BACKGROUND: The aim of this survey was to determine the practice of authorization and reporting of results in clinical biochemistry laboratories in the UK. METHOD: Questionnaires were distributed to the heads of clinical biochemistry departments through the National Audit Committee of the Association of Clinical Biochemists. The standards surveyed were based on guidelines for the reporting of results produced by the Royal College of Pathologists and the relevant Clinical Pathology Accreditation standards. RESULTS: Completed questionnaires were received from 137 laboratories. Workload ranged from 15,000 to 750,000 requests per annum (median 276,883). Most laboratories (98%) release results electronically to at least some wards in real-time. Areas where difficulties were identified included identifying requests that had posed specific questions and access to clinical information at the authorization stage, recording clinical advice given, and ensuring comments remained attached to printed reports or were on the same screen on computer reports. All but six laboratories had consultant advice available, including out of hours, but only 17% had an arrangement for clinical authorization to occur out of hours. CONCLUSION: Only 45 laboratories (33%) were able to achieve 100% compliance with the standards that currently exist, but many others showed evidence of good practice. The practical obstacles still to be overcome include limitations in the capabilities of laboratory computer systems, the lack of accessible electronic clinical records, the difficulties of covering work out of hours and insufficient appropriately trained staff.

Chemistry, Clinical↗

Pediatric laboratory medicine: current challenges and future opportunities.

The practice of pediatric laboratory medicine involves unique challenges related to development, nutrition, growth, and diseases during different periods of infancy, childhood, and adolescence. This article discusses key aspects of pediatric laboratory medicine faced by clinical pathologists, clinical laboratory scientists, and clinicians, including point-of-care testing, preanalytic variables, analytic factors, age-specific reference intervals, esoteric laboratory tests, clinical impact, andfuture opportunities. Although challenging, pediatric laboratory testing offers many opportunities for improved patient care, clinical- and laboratory-based research, and education.

Chemistry, Clinical↗

Enhancing the financial performance of a health system laboratory network using an information system.

We describe the improvements created by successful implementation of a laboratory information system for a multi-institutional integrated delivery system, including an analysis of the financial results. Conditions at the outset of the project, methods of management and project design, selected aspects of services redesign and consolidation, integration of services among the sites and their effects on laboratory staff and productivity are illustrated. A method for and example of measuring the financial outcomes in the sense of quantifiable improvements in operating expenses and new revenue for a whole health system clinical laboratory computer system are discussed. In this health system, the measurable financial improvements facilitated by an information system were the ability to control operating expenses and to grow the hospital laboratory network through the development of an outreach program. With organizational commitment to process innovation and improvement, using team processes and customer-driven decision-making criteria, the financial performance of our consolidated laboratory network was enhanced substantially. A fully implemented laboratory information system is considered the major enabler of positive change when combined with a genuine commitment from all levels of staff and leadership. Over time, this system's financial return is several times that of the information system investment.

Clinical Laboratory Information Systems↗

Population-based study of repeat laboratory testing.

BACKGROUND: Test repetition could be a readily modifiable component of laboratory utilization. Laboratory test repetition has not been rigorously studied at a population-based level. Our objective was to determine the prevalence of, and charges associated with, repetition of eight common laboratory tests. METHODS: We performed a cross-sectional study using high-quality, population-based clinical databases that included adults in Eastern Ontario, Canada, between September 1999 and September 2000 for incidence of repeating eight common laboratory tests (hemoglobin, sodium, creatinine, thyrotropin, total cholesterol, HDL-cholesterol, ferritin, and hemoglobin A(1C)). Tests were classified as potentially redundant if repeated within the test's baseline testing interval. For creatinine, sodium, and hemoglobin, only tests repeated in the community were considered. For a sensitivity analysis, we varied the repeat interval by 25%, excluded tests repeated by different physicians, and excluded repeats of normal tests. RESULTS: Almost 4 million tests were conducted during the study year. Most tests (76%) were conducted on patients in the community. More than one-half of all people in the population had at least one laboratory test, with an overall testing rate of 367 tests per 100 people per year. Repeat testing within 1 month accounted for 30% of all utilization (109 repeat tests per 100 people per year). Repetition was more common in hospitalized patients, varied extensively among tests, and was concentrated in a limited number of people. For the eight tests included in the study, charges of potentially redundant repetition in adults totaled between 13.9 and 35.9 million dollars (Canadian) annually. CONCLUSIONS: Laboratory test repetition is very common, makes up a significant component of overall test utilization, and is costly.

Adolescent↗

Inter-laboratory evaluation of the COBAS INTEGRA 400 analytical system.

COBAS INTEGRA 400 is a random-access analytical system consolidating assays for clinical chemistry analytes, electrolytes, serum proteins, drugs of abuse and therapeutic drugs. Analytical performance and practicability of the instrument were evaluated in seven laboratories over a 2-year period in parallel with system development. Good within-run and total imprecision for all assays was observed with a few exceptions for specimen pools with low concentration or activity. The coefficients of variation for total imprecision were well below 3.0% for clinical chemistry analytes and electrolytes, and below 5.0% for serum proteins and therapeutic drugs. Method comparisons demonstrated a good agreement with the various systems used for comparison, with slopes varying typically from 0.94 to 1.05, and Spearman correlation coefficient generally > 0.975. Accuracy was verified by recovery of controls and certified reference materials within 90 to 110% of target values. Assay ranges were linear within +/- 5%. No carry-over on reagent or sample pipetting systems was observed. Manufacturer-specified interference limits and onboard stabilities of reagents were confirmed. A time study for calculating direct personnel times and total processing time was carried out in three laboratories under different conditions including consolidated, STAT and dedicated use. On a scenario-independent basis, the total working time was shorter on the COBAS INTEGRA 400 than on routine systems in all three laboratories. Personnel time, in particular, was significantly reduced when compared to routine instruments. In general, system practicability was judged very positively in all laboratories. Owing to its versatility, the instrument is best placed as a consolidated workstation in small- to medium-sized laboratories or as an instrument for special determinations such as serum proteins, drugs, urinalysis or emergency analyses in large laboratories.

Blood Proteins↗

EC4 European Syllabus for Post-Graduate Training in Clinical Chemistry and Laboratory Medicine: version 3 - 2005.

The EC4 Syllabus for Postgraduate Training is the basis for the European Register of Specialists in Clinical Chemistry and Laboratory Medicine. The syllabus: Indicates the level of requirements in postgraduate training to harmonise the postgraduate education in the European Union (EU); Indicates the level of content of national training programmes to obtain adequate knowledge and experience; Is approved by all EU societies for clinical chemistry and laboratory medicine. The syllabus is not primarily meant to be a training guide, but on the basis of the overview given (common minimal programme), national societies should formulate programmes that indicate where knowledge and experience is needed. The main points of this programme are: Indicates the level of requirements in postgraduate training to harmonise the postgraduate education in the European Union (EU); Indicates the level of content of national training programmes to obtain adequate knowledge and experience; Is approved by all EU societies for clinical chemistry and laboratory medicine. Knowledge in biochemistry, haematology, immunology, etc.; Pre-analytical conditions; Evaluation of results; Interpretations (post-analytical phase); Laboratory management; and Quality insurance management. The aim of this version of the syllabus is to be in accordance with the Directive of Professional Qualifications published on 30 September 2005. To prepare the common platforms planned in this directive, the disciplines are divided into four categories: Indicates the level of requirements in postgraduate training to harmonise the postgraduate education in the European Union (EU); Indicates the level of content of national training programmes to obtain adequate knowledge and experience; Is approved by all EU societies for clinical chemistry and laboratory medicine. Knowledge in biochemistry, haematology, immunology, etc.; Pre-analytical conditions; Evaluation of results; Interpretations (post-analytical phase); Laboratory management; and Quality insurance management. General chemistry, encompassing biochemistry, endocrinology, chemical (humoral), immunology, toxicology, and therapeutic drug monitoring; Haematology, covering cells, transfusion serology, coagulation, and cellular immunology; Microbiology, involving bacteriology, virology, parasitology, and mycology; Genetics and IVF.

Chemistry↗

Preanalytical variability: the dark side of the moon in laboratory testing.

Remarkable advances in instrument technology, automation and computer science have greatly simplified many aspects of previously tedious tasks in laboratory diagnostics, creating a greater volume of routine work, and significantly improving the quality of results of laboratory testing. Following the development and successful implementation of high-quality analytical standards, analytical errors are no longer the main factor influencing the reliability and clinical utilization of laboratory diagnostics. Therefore, additional sources of variation in the entire laboratory testing process should become the focus for further and necessary quality improvements. Errors occurring within the extra-analytical phases are still the prevailing source of concern. Accordingly, lack of standardized procedures for sample collection, including patient preparation, specimen acquisition, handling and storage, account for up to 93% of the errors currently encountered within the entire diagnostic process. The profound awareness that complete elimination of laboratory testing errors is unrealistic, especially those relating to extra-analytical phases that are harder to control, highlights the importance of good laboratory practice and compliance with the new accreditation standards, which encompass the adoption of suitable strategies for error prevention, tracking and reduction, including process redesign, the use of extra-analytical specifications and improved communication among caregivers.

Clinical Laboratory Techniques↗

Should pediatric echocardiography be performed in adult laboratories?

OBJECTIVES: Current health care management has resulted in a change in referral patterns. The present study was undertaken to define the efficacy and value of pediatric echocardiography performed and interpreted in adult laboratories. METHODS: We reviewed the findings in 100 consecutive pediatric patients 1 month to 18 years of age referred for possible heart disease and evaluated previously by echocardiography performed in an adult laboratory. Technical adequacy and interpretation of the echocardiogram at the outside facility was correlated with our final diagnosis. RESULTS: Of the studies, 32 (32%) were performed in hospital laboratories, and 68 (68%) in physician offices. A total of 52 (52%) of the 100 patients arrived with an outside diagnosis in agreement with our final diagnosis. Technical difficulties were reported in 14 (14%) studies by the original laboratory; we felt that 32 (32%) studies were inadequate. Interpretation or communication between the outside echocardiography laboratory, primary care physicians, and patients' family was erroneous in 32 (32%) cases. Repeat echocardiography was necessary in 38 (38%) patients (6 because of planned surgery). If initial referral had been to our own institution, 25 to 30 patients would not have undergone echocardiography. CONCLUSIONS: Slightly more than half of echocardiography studies performed in pediatric patients in adult laboratories were technically adequate and interpreted correctly with proper physician-family communication. Many patients require repeat studies on further referral. A significant number would be spared echocardiography if they were sent to a pediatric cardiology center initially.

Adolescent↗

[Analysis of productivity, quality and cost of first grade laboratories: blood biometry].

OBJECTIVE: Assessment of productivity, quality and production costs and determination of the efficiency of top grade clinical laboratories in Mexico. METHODS: Ten laboratories were selected from among the total number (52) existing in Mexico City, and the Donabedian model of structure, process and results were applied. Blood count was selected as a tracer. RESULTS: The principal problems found were: inadequate distribution of trained human resources, poor glass material, inadequate analytic process and low productivity. These factors are reflected in the unit costs, which exceed reference laboratory costs by 200%. Only 50% of the laboratories analyzed generate reliable results. Only 20% of the laboratories studied operate efficiently. CONCLUSIONS: To solve the problems identified requires integral strategies at different levels. A specific recomendation for the improvement of quality and productivity is an assessment of the cost/benefit of creating a central laboratory and using the remaining sites exclusively for the collection of samples.

Biometry↗

The state and territorial public health laboratory: program activities, organization and prospects for the future.

During the past two years we have studied the characteristics of state and territorial public health laboratories in an attempt to develop guidelines for considering reorganization of laboratory services in Massachusetts. Only a few recent monographs have dealt with this topic and, to our knowledge, the functional and organizational characteristics of these laboratories have not been reviewed. The state public health laboratory system affords an excellent example of applied laboratory science or technology organized to provide basic public health services. In this paper the programs and organization of the state public health laboratory are reviewed, and a functional basis more responsive to society's current needs is suggested.

Economics, Medical↗

Variability and laboratory factors affecting the sperm chromatin structure assay in human semen.

During the past decade, the sperm chromatin structure assay (SCSA) has become an important tool for assessing semen quality in the human andrology laboratory. The SCSA uses the metachromatic properties of the fluorescent dye acridine orange (AO) in combination with flow cytometry to determine the sperm DNA susceptibility to denaturation in situ. The objective of this study was to evaluate laboratory factors affecting the SCSA and the variation between replicates. Semen ejaculates from 3 healthy volunteers were analyzed using the SCSA protocol as described by Evenson and Jost (2000), determining the X-mean, Y-mean, DNA fragmentation index (DFI), standard deviation of DFI (SD-DFI), and high DNA stainability (HDS). In experiment 1, the effects of thawing time, time of day, day, laboratory technician, donor, and incubation period before analysis were investigated. In experiment 2, the effects of sheath fluid, AO equilibration buffer, day, laboratory technician, donor, and incubation period before analysis were investigated. A significant difference was found between the 3 donors with respect to the X-mean, Y-mean, DFI, SD-DFI, and HDS. It was shown that incubation of the semen samples on ice postthaw had a significant effect on the X-mean, Y-mean, DFI, and SD-DFI. The laboratory technician conducting the analysis accounted for up to 15.4% for the variation of the SCSA measurements. The time of day affected the variation for the Y-mean (23.5% of the total variation of the Y-mean), and the day affected the variation for the X-mean (82.8% of the total variation of the X-mean). Incubation on ice for 5 to 25 minutes postthaw had a significant effect on the DFI and SD-DFI in both experiments. This study shows that several protocol steps in the SCSA affect the results obtained from the assay. Precise protocol description and standardization of the SCSA are therefore essential to achieve high agreement within and between different laboratories.

Chromatin↗