The intrauterine turnover of thiamin in preterm and full-term infants

A quality assurance program of the Chagas' disease laboratory network of Argentina has been conducted by the National Reference Center since 1988, with the aim of assessing the reliability of serologic test results. Chagas' disease is endemic in Argentina, but the prevalence of seropositivity for Trypanosoma cruzi among 18- to 20-year-old men decreased from 5.8% in 1981 to 1.8% in 1994. About 600 laboratories form the Chagas' disease laboratory network, with main central laboratories in each of the 24 provinces in Argentina. The quality assurance program promotes regular use of good laboratory practice and internal and external quality control to improve performance of the participants; it also provides technical assistance and guidelines. Eventual corrective measures are discussed in workshops. Results of the first external evaluation by proficiency testing of serum panels and confirmation of results for 58 of the main laboratories reveal that from 1988 to 1994 the rate of agreement has increased.     

Clinical microbiology quality assurance program: a Taiwan experience

Quality assurance programs have been established during the last two decades in developed countries to promote high quality performance in clinical laboratories. In Taiwan, such a program for clinical microbiology laboratories has been in place since July 1987. It has been supported by the Department of Health, Executive Yuan, R.O.C. and was set up by the authors. The manpower status, facilities and equipment, and performance of clinical laboratories were investigated during the first year and standards of laboratory quality were recommended. Since then, under a continuing education program, we have conducted seminars, symposia, workshops, short-courses or panel discussions approximately 4 times a year. There have been about 150 participants per session and they have come from local hospitals (primary care hospitals), regional hospitals (secondary care hospitals) and medical centers (tertiary care hospitals). Proficiency test specimens or external unknown specimens were sent to all the laboratories twice a year and approximately 3 specimens were used each time for the evaluation of each laboratory's diagnostic capability and quality of service. Results indicated that there were tremendous improvements in the quality of laboratory performance. At the same time, several laboratory manuals describing the methods of quality control of clinical specimens, test procedures, media and reagents, personnel management and a compilation of reports etc. were published as guidelines of basic requirements for each level of the laboratories. For local hospital laboratories in remote areas, several regional hospitals or medical centers with high quality laboratories were selected to serve as back-ups. Our evaluation has shown that the performance and quality of service provided by most clinical microbiology laboratories in Taiwan have now reached nearly the level of those found in the so-called "developed countries".     

Appropriate laboratory use of microbiological testing for quality control and nosocomial infection control

Useful information from clinical microbiological tests is required for clinical diagnosis and treatment of infectious disease, whereas concern about the quality of information is still low. To provide reliable information in clinical microbiological testing, it is necessary to control the quality of clinical specimens, because of its random character. Through effective use of laboratory testing database, it will be possible to shift away our vague management of pre-analytic phase of quality control so far to its established system based on objective evaluation. During the past 4 years, after the introduction of microbiological tests and information system in our hospital, the characteristics of sputum have become worse contrary to our expectations. This suggests that quality control needs successive improvements, even in service departments such as clinical laboratories. Application of laboratory testing database to nosocomial infection control is considered to be a performance of post-analytic phase of quality control from the viewpoint of effective use of laboratory data. We presented in this paper our practical application of the database to the short-term and long-term control of nosocomial infection.     

External Quality Assessment of stat test intralaboratory turnaround times. Pilot study from the Members of the Working Group for the Standardization and Promotion of Turnaround Time Control under the Auspices of the Comitato Italiano per la Standardizzazione dei Metodi Ematologici e di Laboratorio

We describe procedures, results and prospects of a pilot program in External Quality Assessment (EQA) of the stat test intralaboratory turnaround times. Our goals are to promote quality by systematic monitoring and comparison of performances by laboratories, continuous investigation into the state of the art of the processes from receipt of sample to transmission of results and creation of a data base for standardization of measures and definition of consensus values for turnaround time. Of 30 laboratories invited to participate, 25 took part, agreeing to record times of arrival and transmission for all determinations of three analytes (blood hemoglobin, serum/plasma potassium and plasma prothrombin time) for seven consecutive days and to continue for one or more further periods of seven days as necessary if there were less than 300 determinations for each analyte. Within a preset time limit, data were sent by e-mail on an Excel file and we sent back two reports per analyte, showing: i) the graph for time vs. percentage of tests completed and several measures of turnaround time; ii) results of all laboratories in graph form, allowing each laboratory to identify only its own data. The high proportion of participating laboratories among those invited (83%) encourages us to implement the EQA program systematically, on a half-yearly basis, extending it to all laboratories wishing to participate in Italy or elsewhere in Europe.     

User's requests (from a practitioner's perspective)

As a practitioner, I have to rely on outside clinical laboratories and affiliated hospitals to perform laboratory tests. In this abstract, I describe specific problems I have encountered with third-party laboratories, and propose solutions for these problems to optimize use of laboratory tests. BLOOD TESTS: The most frequent problem in ordering blood tests is the lack of detailed information regarding sampling conditions. I often have to call laboratories to check whether the sample should be serum or plasma, what volume is needed, whether the sample should be cooled, etc. I propose that clinical laboratories should provide practitioners' manuals that describe specific sampling information. ULTRASONOGRAPHY: Most laboratories do not keep the data from ultrasonographic tests. The lack of these is most problematic when test results are interpreted differently by laboratories and by practitioners. Retaining the data would also help private laboratories improve the quality of the test by enabling them to compare their interpretations with others'. ANNUAL MEDICAL SCREENING: Even if an abnormal finding is detected at medical screening clinics, the final diagnosis is usually not sent back to the screening facilities. This is highly recommended to establish an official system that mediates the feedback to screening centers. MRI: Due to miscommunication between practitioners and radiologists, the test is sometimes performed inappropriately. A thorough consultation should occur before the test to clarify specific goals for each patient. PATHOLOGICAL TESTS: Interpretation of results is often inconsistent among laboratories. Independent clinical laboratories tend to report results without indicating sample problems, while pathology departments at affiliated hospitals tend to emphasize sample problems instead of diagnosis or suggesting ways to improve sample quality. Mutual communication among laboratories would help standardize the quality of pathological tests.     

铝酸钠溶液在线自动检测系统

分析了实施铝酸钠溶液在线自动检测系统的目的和必要性,描述了该系统的测定原理、总体结构及试运行情况,程序运算得到的溶液浓度值与化验室分析值的误差一般不超过±2 5%,精度满足生产工艺要求。     

Evaluation of a dual-color flow cytometry immunophenotyping panel in a multicenter quality assurance program

A basic immunophenotyping panel that employed dual-color combinations of fluorescein isothiocyanate (FITC) and phycoerythrin (PE) conjugated monoclonal antibodies (mAb; FITC-CD45/PE-CD14, FITC-IgG1/PE-IgG2, FITC-CD3/PE-CD8, FITC-CD3/PE-CD4, FITC-CD3/PE-CD16 + PE-CD56, and PE-CD19) was utilized in a quality assurance program to determine whether the 4 laboratories participating in a multicenter AIDS study obtained similar lymphocyte subset percentage values for T cells, B cells, NK cells, and CD4+ and CD8+ T cells. Over a 1 1/2 year period, 78 shared peripheral blood specimens were prepared and analyzed in each laboratory. The CD45bright CD14- percentage for each specimen was used to correct that individual's lymphocyte subset values. Interlaboratory coefficients of variation (CV) for the human immunodeficiency virus type I (HIV) seronegative (n = 38) and HIV-seropositive (n = 40) specimens using this panel were < 3% for total T cells; < 5% for CD4+ T cells and CD8+ T cells; < or = 17% for B and NK cells; and < 8% for CD4T/CD8T ratios. The 6-tube basic immunophenotyping panel has several notable features: a) for clinical studies, it permits comprehensive evaluation of an individual's major lymphocyte subsets, i.e., T, B, NK, and CD4+ and CD8+ T cells; b) for interlaboratory proficiency testing programs, it allows the detection of differences among laboratories in measurements of several functionally distinct cell populations; and c) for within-sample quality assurance, it provides several quality control checks, including the lymphosum, i.e., the sum of an individual's corrected T+B+NK values, a sum that was generally 100 +/- 5% on the HIV-seronegative specimens analyzed in this study.     

Control of avian encephalomyelitis: a historical account

Avian encephalomyelitis control methods were not developed until the 1950s although the disease had been discovered and described over 20 yr earlier. Inability to transmit the infection by other than intracerebral inoculation, lack of suitable immunologic methods, the unknowing use of immune chickens or embryos for experimental studies, and reliance on a highly adapted strain of virus rather than fresh field isolates were the main reasons for a general lack of progress. In the absence of supportive experimental data, at least two commercial breeding organizations turned to the use of a crude chicken brain-propagated virus for vaccination of breeder replacement flocks in the 1950s. This control procedure turned out to be practical and efficacious. Development of suitable embryo infection methods and immunologic tests and the chance finding that antibody-free flocks were essential for experimental studies led to the development of embryo-susceptibility tests to identify immune breeder flocks and formed the basis for another commercially applied control program, the testing and selection of only immune flocks for hatching purposes. The application of the new testing methods coupled with a switch from the adapted Van Roekel strain of virus to fresh field isolates for experimentation resulted in a rapid unraveling of the epizootiology and pathogenesis of the disease and also to the development of a safe and effective vaccine that was licensed for administration to breeder replacements in 1962.     

Organization of laboratories in the German Democratic Republic

The effectivity of the clinical medicine becomes increasingly dependent on the efficiency of medico-experimental subjects, to which belong pathological chemistry and clinical biochemistry as well as haematology. The scientifically proved increasing demands made on the laboratories concern the quality of the results of investigations, constantly increasing numbers of investigations as well as a considerable enlargement of the investigation programmes. Adequate developments of workman are not to be expected. The requirements are to be met by the increase of the working productivity, for which a good organisation of work the use of mechanisation and automatisation means for the elaboration of large series of investigations are the prerequisite. A high degree of centralisation ascertains the effectivity of the adequate investments. Exceeding the ascertained foundations for a project of organisation of the laboratory work in the GDR in the next time still various problems must be solved which especially influence the organisation. Among others they concern the necessary investigation programme for the general practitioner in an out-patient practice, moreover the establishment of investigation programmes for several levels of care, the necessary quality (precision and exactness) of the results of investigations, the suitableness of stripe tests and the influence of preanalytic factors and especially of the biorhythmics on the findings of investigations. The tendencies described are accompanied by the danger that the reciprocities between clinic and laboratory becoming increasingly more necessary for the interpretation and classification of laboratory findings into the symptom complex become rather loose. Therefore, it will be one of the most important tasks of future to develop together reorganisation and collaboration.     

Inter-laboratory difference among eleven clinical laboratories in the Okayama City area

The aim of the present study was to find the cause of inter-laboratory differences in laboratory test data and to examine whether control assessment helps to reduce inter-laboratory differences. Blood and serum samples of one healthy subject and one subject with liver cirrhosis were analyzed by 11 laboratories in the Okayama City area. No differences were found in the assay units of 26 tests surveyed. However, considerable differences were observed in test data, reference interval, and clinical level (CL), though most laboratories pointed out that the test data for the normal subject was within the reference intervals and those for the patient with liver cirrhosis showed abnormalities in tests for liver function. The difference in reference intervals was serious in the tests of direct bilirubin (D-Bil), thymol turbidity test (TTT), alkaline phosphatase (ALP), gamma-glutamyltranspeptidase (GGTP) and choline sterase. Marked differences in CLs were found in the tests of D-Bil, TTT, ALP, GGTP, creatine phosphokinase, amylase, heavy density lipoprotein cholesterol and white blood cell count. However, three hepatologists independently suggested that such inter-laboratory differences would not seriously affect a clinical decision on the disease status of the cirrhotic patient. Most tests that showed a trend error in a recent quality control survey appeared to have the same trend in the present study. These results indicate that inter-laboratory differences occur at various levels and control assessment are helpful in establishing, and therefore reducing, the level of inter-laboratory differences.     

Workshop on screening for cancer of the uterine cervix in Central America

This article describes the objectives and content of a workshop held in Managua, Nicaragua, during November 1995, on screening for cervical cancer. The aims were to discuss cost-effective models of screening in countries with a high incidence of cervical cancer and to reach a consensus on principles for screening that is balanced with a country's resources. The workshop aimed to develop a planning framework and to identify program strengths and weaknesses by country. In 1990 there were 25,000 deaths due to cervical cancer in Central America; even so, most countries attach a low priority to cervical cancer screening. Workshop plenary sessions were devoted to discussions about the natural history of cancer of the cervix and the implications for screening, the high costs of human papillomavirus (HPV) tests, approaches to national registries of cervical cancer, screening issues in Central America, downstaging, laboratory quality control issues, treatment of abnormalities, recruitment of women, and IEC. This report includes individual country program reports for Nicaragua, Panama, Haiti, the Dominican Republic, Guatemala, Honduras, and St. Vincent and the Grenadines. Participants concluded that priority should be placed on education about cancer and cancer of the cervix and education of primary health care professionals. It was agreed that all participating countries should begin pilot programs adapted to resource availability, with the idea of a later nationwide expansion. Health care professionals who treat women during the prime reproductive years should use the opportunity to identify women at high risk of invasive cancer. There is overcoverage of women aged under 35 years and insufficient coverage of women aged 35-64 years. Health programs need to enlist the help of women's groups in creating a need and demand in communities. Cytology laboratories need to provide quality services.     

Multivariate approach to quality control in clinical chemistry

When monitoring analyzer performance in the clinical setting, laboratories are required to test multiple concentrations of control material on a daily basis. Because of the nature of laboratory testing, there is the potential for correlation between the concentrations of control material being monitored. Although traditional clinical quality-control approaches make an underlying assumption of independence with respect to the control concentrations, this will not always be the case. The presence of correlation in some circumstances suggests the use of a new approach for evaluating clinical laboratory monitoring data: the multivariate control chart. Such a chart (the chi2 chart) is evaluated and compared with traditional quality-control approaches used in the laboratory setting. Results indicate that the multivariate approach provides an attractive alternative to many traditional methods of quality assurance when control concentrations are correlated.     

The quality of impressions for crowns and bridges received at commercial dental laboratories

OBJECTIVE: To determine the quality of impressions for crown and bridge work made in general dental practice. DESIGN AND SETTING: All impressions for crown and bridge work which had been sent to four commercial dental laboratories in the UK were assessed by two examiners, each laboratory being visited on two occasions. MATERIALS AND METHODS: 290 cases which had been received by the laboratories on the days of the visits were assessed for a number of factors related to quality. There was no selection or rejection--all impressions received were examined. RESULTS: Flexible plastic trays were used for the majority of working impressions for crown and bridge work in general dental practice (72%), many had been re-used (> 13%), defects in the recording of the prepared teeth were common, and cross infection control was not routine. CONCLUSIONS: Quality standards for impressions for crown and bridge work in general dental practice in the UK are a cause for concern if the sample of cases seen in this study is typical.     

Corrosion Response of a Decommissioned Deteriorated Bridge Deck

This paper summarizes the results of field tests on the decommissioned Montreal Dickson Bridge, undertaken over a grid of 0.25 by 0.25?m on four randomly selected 5 by 6?m deck patches, and the associated laboratory tests as part of a detailed research program aimed at determining why the bridge deteriorated so rapidly. The basic cause of deterioration was determined to be the lack of quality control (concrete mix composition, placing, compaction, and curing) and the resulting higher permeability of the concrete cover and the associated chloride ion ingress. As a consequence, the resistivity of the concrete was low and reflected in a high steel bar mass loss due to corrosion at several locations on the bridge after a period of only 35 years.     

Reliability and feasibility of a near patient test for C-reactive protein in primary care

BACKGROUND: The applications of new diagnostic technologies such as near patient tests are relevant to the further development and potential of primary care. Through their use, doctors in the community may increase the accuracy of their diagnoses and improve their ability to monitor disease. A reliable indicator of disease activity in various clinical conditions is C-reactive protein (CRP) and a near patient test for this is now available, although there is little information on its use outside hospitals. AIM: A study was set up to evaluate the feasibility of using a novel near patient test for CRP in primary care to validate the results against the laboratory "gold standard' for CRP (Beckman Array) and to compare results with the usual inflammation test used in general practice. METHOD: Prospective recording of CRP as a near patient test on an "intention to investigate' basis, with validation of results against the Beckman Array system for CRP and hospital laboratory erythrocyte sedimentation rate results, in six general medical practices in Birmingham. Main outcome measures were change in local laboratory usage, characteristics of patients chosen for testing, use of quality control, and comparison of readings with results from the same sample sent to an independent laboratory. RESULTS: Tests of CRP levels were rarely requested before the study was undertaken. During the 3-month study period, 181 near patient tests were carried out, 146 (81%) to establish a diagnosis and the remainder for disease monitoring. Out of the tests, 67% were performed by general practitioners, mostly during the consultation itself. Using a cut-off level of 10 mg I-1, the near patient test and the Beckman Array gave results which agreed in 84% of cases. The sensitivity and specificity of the near patient test results were 97 and 79%, respectively. The predictive value of a positive result was 59% and that of a negative result was 99%. Cohen's Kappa was 62% and the overall mean bias for results in the range of the test was 6.11 mg I-1 (SE = 3.07 mg I-1). Each test took 6 min on average to perform, including all preparations, blood letting, performing the test and averaging the time for quality control estimations. The cost per test averaged pounds 1.72, rising to pounds 4.17 including labour, capital costs, quality controls and consumables (general practitioner performing the assay at average frequency found in this study). CONCLUSIONS: Measurement of CRP is rarely used in primary care and awareness of its value could be raised. This near patient test proved feasible for use by general practitioners and practice nurses. Its reliability compared with a laboratory result was satisfactory overall, and excellent with adequate operator technique.     

"Ocean-to-Ocean Project": a transcontinental external quality assessment trial in clinical chemistry realized throughout Eurasia

More than 800 diagnostic laboratories situated throughout the Eur-Asian continent--from the Pacific Coast up to the North Sea littoral--were involved in a common survey of External Quality Assessment (EQA). It consisted of the simultaneous measurement of up to 30 analytes of 'general' clinical chemistry using the same batch of control material. The laboratories were associated in four EQA institutions: SKZL (The Netherlands), OQUASTA (Austria), SEKK (Czech Republic) and BKKSystem (Community of Independent States). The results demonstrated the feasibility of such a large-scale survey and provided a realistic idea about the state-of-the-art of laboratory diagnosis in these countries: Besides some local specific problems, such as poor quality of water or the forced use of reagents and calibrators from different sources, there are general problems hindering an efficient process of 'harmonization' in laboratory medicine, namely, the high methodological dispersion especially in the case of enzymes and of some organic analytes. At the same time there is a potential necessity for more concentrated implementation of internal quality assessment into the routine work of laboratories.     

Influence of fungi associated with bananas on nutritional content during storage

Clinical diagnosis is one of the areas in which flow cytometry (FCM) has gained wide popularity and FCM now plays a crucial role in several aspects of medical hematology. It has progressively replaced many traditional laboratory tests due to its greater accuracy, sensitivity and rapidity. Unfortunately, among the very large number of its potential applications, only a minority of flow cytometric protocols have been standardized. Numerous factors are responsible for variation in analytical conditions and may affect results obtained by FCM. All these variables can be schematically divided into three major groups: factors related to the biological samples, immunological and accessory reagent factors and factors associated with the use of instruments. The quality control program must monitor and evaluate all aspects of the procedure. This includes the following main aspects: 1) performance of the flow cytometer, 2) specimen collection, transportation and maintenance of its integrity, 3) reagents, particularly monoclonal antibodies and 4) sample measurements, data acquisition and their interpretation. Procedures described here are designed to assess all the settings which affect the reliability, reproducibility and sensitivity of the cytometer in order to ensure identical conditions on a daily basis.     

Components of laboratory accreditation

Accreditation or certification is a recognition given to an operation or product that has been evaluated against a standard; be it regulatory or voluntary. The purpose of accreditation is to provide the consumer with a level of confidence in the quality of operation (process) and the product of an organization. Environmental Protection Agency/OCM has proposed the development of an accreditation program under National Environmental Laboratory Accreditation Program for Good Laboratory Practice (GLP) laboratories as a supplement to the current program. This proposal was the result of the Inspector General Office reports that identified weaknesses in the current operation. Several accreditation programs can be evaluated and common components identified when proposing a structure for accrediting a GLP system. An understanding of these components is useful in building that structure. Internationally accepted accreditation programs provide a template for building a U.S. GLP accreditation program. This presentation will discuss the traditional structure of accreditation as presented in the Organization of Economic Cooperative Development/GLP program, ISO-9000 Accreditation and ISO/IEC Guide 25 Standard, and the Canadian Association for Environmental Analytical Laboratories, which has a biological component. Most accreditation programs are managed by a recognized third party, either privately or with government oversight. Common components often include a formal review of required credentials to evaluate organizational structure, a site visit to evaluate the facility, and a performance evaluation to assess technical competence. Laboratory performance is measured against written standards and scored. A formal report is then sent to the laboratory indicating accreditation status. Usually, there is a scheduled reevaluation built into the program. Fee structures vary considerably and will need to be examined closely when building a GLP program.     

Effects of Induced Vibrations on Early Age Concrete

The purpose of this investigation was to conduct a laboratory test program on how much induced vibrations on concrete during the period between initial set and final set affect the attainable strength of concrete. To achieve this purpose, a laboratory test program was conducted. The laboratory program consisted of casting 144 76?mm by 152?mm (3×6?in.) concrete cylinders and subjecting them to one of two levels of vibration for either 1 or 2?min at five different ages ranging in time from before, during, and after the setting period for the concrete. The levels of vibration correspond to typical frequencies of vibratory soil compactors and the peak particle velocity produced by the compactors. Both compression and splitting tensile tests were performed. The results of the laboratory study indicate that vibratory soil compaction should not be considered a significant hazard to foundation strength as long as the vibrations are within the limits in this study.