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PubMed1995

National and regional regulations on minimal requirements, quality control and accreditation for clinical laboratories in Italy.

The national law concerning minimal requirements and quality control for clinical laboratories, dating back to 1984, is a decree of the President of the Council of Ministries (DPCM). Minimal requirements are established regarding general organization of the laboratory, instrumental equipment's, the personnel, the list of analytical tests, the director of the laboratory and its responsibilities, and quality control systems. Concerning regional legislation, since 1978 eighteen regions and the two autonomous provinces of Trento and Bolzano have issued--in the matter of minimal requirements and quality control for clinical laboratories, and point of specimen collection--laws, decrees, resolutions, deliberations, regulations and circulars that have determined in Italy a disparity of situations and a non-homogeneous regulation. The prerogative of the regions has been recently confirmed (laws 502/1992 and 517/1993): the introduction of appropriate procedure for the accreditation of both public and private services who want to operate within the National Health Service is defined as impelling. The homologation to operate may be acquired if the structure or the service actually has the instrumental, technical, and professional endowment corresponding to criteria established on a national basis. The national legislator deemed it necessary to establish a coordination on a national basis to uniform and standardize protocols, operating procedures, and methods of evaluations. The Istituto Superiore di Sanità (ISS) can have a key role in this coordination activity, mainly concerning technical/scientific aspects.(ABSTRACT TRUNCATED AT 250 WORDS)

Accreditation↗
PubMed1999

Escherichia coli ATCC 35218 as a quality control isolate for susceptibility testing of Haemophilus influenzae with haemophilus test medium.

Current National Committee for Clinical Laboratory Standards (NCCLS) susceptibility guidelines for quality control testing with Haemophilus influenzae do not include a beta-lactamase-producing strain that could detect the deterioration of the beta-lactamase inhibitor components of amoxicillin-clavulanic acid, ampicillin-sulbactam, and piperacillin-tazobactam. The objective of the study was to determine if comparable quality control results for Escherichia coli ATCC 35218, a beta-lactamase-producing strain, would be produced for the three beta-lactam-beta-lactamase inhibitor agents with Haemophilus test medium and Mueller-Hinton medium. The criteria used in this study to determine if Haemophilus test medium was acceptable for quality control testing of E. coli ATCC 35218 was that 100% of the results obtained with an antimicrobial agent-methodology combination needed to be within the acceptable NCCLS ranges established with Mueller-Hinton medium. The MIC testing results obtained by the broth microdilution and E-test methods with amoxicillin-clavulanic acid and piperacillin-tazobactam were all within the NCCLS ranges; however, the results obtained with ampicillin-sulbactam by both methods were not within the NCCLS ranges. Acceptable results were obtained by the disk diffusion methodology with ampicillin-sulbactam and piperacillin-tazobactam but not with amoxicillin-clavulanic acid. When performing susceptibility testing with H. influenzae with the beta-lactam-beta-lactamase inhibitors, in addition to quality control testing with H. influenzae ATCC 49247, testing of E. coli ATCC 35218 on Haemophilus test medium is an effective way to monitor the beta-lactamase inhibitors in some antimicrobial agent-methodology combinations.

Culture Media↗
PubMed1983

Results of quality control surveys of radioimmunological determinations of thyrotropin in newborns.

Within the quality control scheme of the Deutsche Gesellschaft für Klinische Chemie, seven quality control surveys of thyrotropin (TSH) determinations in blood dried on filter paper have been carried out since 1980. Ninety-six screening laboratories from 12 European countries took part in these surveys. In a single survey each participant usually analysed four different samples; each of these consisted of three spots of dried blood spiked with defined amounts of thyrotropin. For the evaluations of the surveys the participants were asked to give information about their analytical results, and from these, their diagnostic classifications. The medians of the analytical results correlated well with the given thyrotropin concentrations, but the individual estimations from different laboratories varied greatly. Major discrepancies of classification were also apparent, both in the given thyrotropin concentrations and in the individual estimations. Two special collaborative studies with nine selected laboratories showed on the one hand that analysis of the largest possible part of the dried blood sample can help to optimize the precision of the results; on the other hand, considerable drawbacks related to the reagents and the methods were sometimes observed.

Blood Specimen Collection↗
PubMed1976

Practical aspects of quality control for radioimmunoassays.

Mechanisms for the quality control of radioimmunoassays are described. They are useful in monitoring the possible sources of error which cause medically invalid results: errors in the radioimmunoassay system itself, in the test environment, in the instrumentation, and in the specimen quality. The application of a total control program permits early detection of malfunctions and can be used for the logical assessment of probable causes and solutions.

Indicators and Reagents↗
PubMed1973

In-use evaluation of a commercially available set of quality control cultures.

Increasing awareness of the need for a uniform quality control program prompted an evaluation of a commercially available set (Bact-Chek) of eight organisms. A protocol was designed in which this set of control cultures was tested simultaneously in the clinical microbiology laboratory of a 400-bed hospital (the Berkshire Medical Center) and in the reference laboratories of the Bacteriology Section of the Center for Disease Control. The results indicate that the Bact-Chek organisms are essentially as advertised: they constitute a basic set of cultures for a quality control program in clinical microbiology. Ninety per cent of the media and reagents (excluding mycobacterial media and reagents) in the clinical laboratory were checked with this set of eight cultures. Additional cultures not in the set were used to check the remaining 10% of the media and reagents.

Bacteria↗
PubMed2004

[The EQUAL-ESTRO external quality control laboratory in France].

PURPOSE: The EQUAL-ESTRO laboratory was set up in 1998 to perform external audits of radiotherapy beams for all the European centres. Until the end of the year 2003, it was funded by EC projects. The external quality control is based on measurements performed with thermoluminescent dosimeters (TLD) sent by postal mail to the participating centre in order to be irradiated on axis in reference conditions and in conditions close to clinical conditions for photon and electron beams. The EQUAL-ESTRO laboratory also started in 2002, a new TLD control allowed to check the dosimetry of complex clinical fields for photon beams with multileaf collimator (MLC). New geometric and dosimetric checks have also been developed for brachytherapy. MATERIAL AND METHODS: The participating centre irradiates TLDs (7LiF: Na, mg, Ti, TLD 937 [Philitec]) in water at a dose of 2 Gy, calculated with the TPS used clinically, following the EQUAL-ESTRO protocol. RESULTS: Since the beginning of the activities, 46% of the French radiotherapy centres and 55% of the European radiotherapy centres applied to participate to the EQUAL quality control programme. In France, the EQUAL-ESTRO laboratory checked, from 1998 and June 2004, 283 photon beams, 180 electron beams and 61 photon beams with MLC. For all the French beams checks, the following results have been observed: for the photon beams, the results show that about 1% of the measured doses in the reference conditions on axis have been detected outside the tolerance level (deviation between the measured dose and the stated dose > +/- 5%) after a first or a second check. For points checked in photon beams with wedge filter, 2.5% of the beams checked show a deviation > +/- 5% after a first or a second check. For the electron beams, the check has been set up in January 1999. For the 180 electron beams checked, 5% of the measured doses in the reference conditions have been found outside the tolerance level (> +/- 5%). CONCLUSION: These results show clearly the importance of the quality control in radiotherapy in the frame of an external audit. This audit should now be a part of a quality assurance programme in the radiotherapy centres in addition to the internal quality control as planned in the French law (02/03/2004) concerning the external quality control conditions of the radiotherapy treatment units.

Europe↗
PubMed1990

Applied principles of quality assurance and quality control in the histopathology laboratory.

The principles of quality assurance programs and quality control procedures as they are applied to the histopathology section of the laboratory are reviewed. The basic importance of the Standard Operating Procedure Manual is emphasized and the importance of accurate record keeping in tissue reception and accessioning is noted. A detailed look is taken at the quality control measures applied to the repetitive processing sequences involved in the production of stained tissue slides. The problems of the subjective nature of the final assessment of the finished slide are reviewed.

Canada↗
PubMed1997

[Clinical monitoring. A method for quality control].

Clinical monitoring approximates the quality control standards that have been developed by the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) and utilizes clinical indicators to measure the relative quality of the health care given. This method can be used to compare the quality of desired care against actual day by day care. To demonstrate how it can be applied, an example of clinical monitoring performed in a U.S. hospital is presented.

Humans↗
PubMedDate not supplied

Quality control in the pulmonary function laboratory.

Quality control and proficiency testing are well recognized as means for evaluating equipment accuracy and technical proficiency use of spirometry in physicians' offices, clinics, and industry has brought attention to the need for standardization of calibration and testing techniques in pulmonary function testing. Minimum specifications for equipment accuracy provide the basis for consistency of interlaboratory measurements, and familiarity with operation, calibration, and maintenance procedures enhances personnel proficiency.

Calibration↗
PubMed1983

A grading system for bone marrow cytogenetics and its use as a standard for quality control.

A grading system has been developed to assess the quality of the results of bone marrow cytogenetic procedures. The results of 3 1/2 years use of this grading system are reported. This grading system is a satisfactory internal standard for quality control and is adaptable for use as an external standard. The use of such an internal standard will improve the performance of the cytogenetics laboratory and will validate the quality of the results of cytogenetic examination. The use of an external standard will stimulate the standardization and improvement of cytogenetic laboratory techniques and may be used to develop performance standards for accreditation of both bone marrow and other cytogenetic laboratories. Internal and external quality controls have been used in general medical laboratories for many years, and their use should be instituted by cytogenetic laboratories as well.

Bone Marrow↗
PubMed2005

Broth microdilution susceptibility testing of Campylobacter jejuni and the determination of quality control ranges for fourteen antimicrobial agents.

Quality control ranges were developed for broth microdilution testing of Campylobacter jejuni ATCC 33560 against 14 antimicrobials. Cation-adjusted Mueller-Hinton broth containing 2.5% laked horse blood was the preferred medium, with incubation in a microaerobic atmosphere of 10% CO(2), 5% O(2), and 85% N(2) at 36 degrees C for 48 h or 42 degrees C for 24 h.

Anti-Bacterial Agents↗
PubMed1975

Purification and radiochemical quality control of 131I-19-iodocholesterol.

Radiochemical quality control and purification techniques were developed for 131I-19-cholesterol. The amount of ionic 131I-iodide is rapidly determined using instant thin-layer chromatography. Samples of the labeled steroid that contain greater than 8% of ionic 131I-iodide are purified with one of two techniques, both using a weakly basic ion-exchange resin. The first technique, a batch ion-exchange process, is suitable for removing relatively low concentrations of ionic 131I-iodide; if higher concentrations of this radiochemical contaminant are present, the second or column technique is more suitable.

Cholesterol↗
PubMed1988

Inadequate reporting of analytical quality control in the clinical pharmacological literature.

Quality control parameters were surveyed in the clinical pharmacological literature of 1984 and 1985, as published by the European Journal of Clinical Pharmacology, the British Journal of Clinical Pharmacology, and Clinical Pharmacology and Therapeutics. Papers which included newly developed methods gave details about precision and sensitivity in more than 60% and about accuracy and specificity in nearly 30%. Fewer than one-third of all articles containing analytical methods, described by citation only, gave information about precision and sensitivity in the originating laboratory, and accuracy and specificity were reported by less than 10% of them. These data represent an important deficiency in laboratory information in the clinical pharmacological literature.

Periodicals as Topic↗
PubMed1981

Vitamin B12 quality control trials.

The results of regional quality control trials of vitamin B12 assays are reported. Consideration is given to the materials suitable for such trials. The technical and clinical performance of the participants are assessed together with the methods used. The introduction of a target coefficient of variation has produced better identification of good and bad performance and the use of a reference serum has permitted comparison of assays of different methods. The linearity of most methods is suspect and indicates the need for reference sera of varying concentration. Introduction of kits has not generally improved precision and variation between laboratories shows the use of kits can be improved.

England↗
PubMed1992

Quality control for colposcopy in the Florence screening program for cervical cancer.

The authors report on the quality control for colposcopy adopted in the Florence District screening program. The sensitivity of colposcopy was determined on all cases of CIN III recorded in the local cancer registry in a four-year period. However although this showed that a centralized colposcopic clinic employing a limited number of expert operators is superior to the performance of colposcopy in private practice, such a parameter was impractical for further routine quality control since differences among operators were too small and statistically insignificant. Other parameters for quality control were chosen, namely a) the rate of colposcopically directed biopsies performed, b) the detection rate of CIN II or more severe lesions, and c) the positive predictive value of a directed biopsy for CIN II or more severe lesions. Analysis of these indicators after stratification by cytologic report allows the identification of those operators who need additional training and provides useful information for colposcopists to optimize their diagnostic and operative criteria.

Adult↗
PubMed2006

MRI quality control tools for procedures and analyses.

Quality control in MRI includes acceptance tests on the installation of a new scanner and tests representative of the system's performance during clinical practice. The first tests are time consuming and carried out to evaluate the agreement of the system with the prescribed procurement specifications. The second tests identify the equipment malfunction requiring maintenance are not time consuming and are suited to a busy clinical scanner. The paper evaluates the feasibility of the AAPM protocols (1,2) and proposes procedures and practical tools to achieve this purpose. The MRI images, captured from the scanner and transferred in DICOM (Digital Imaging and Communications in Medicine) format by a local network, are analyzed by computerized worksheets and commercial software.

Calibration↗
PubMed2006

Design and implementation of an electronic data recording and processing system for physics quality control checks in external beam radiotherapy.

Quality control (QC) of external beam radiotherapy equipment ensures that commissioning performance is maintained. Paper based data recording is still used for QC, but this is resource intensive in terms of data calculation and processing. Electronic systems of data recording have many advantages; for example, they facilitate the analysis of data on a regular basis, allowing the user to examine the "health" of each machine; they help review and audit local frequencies of each check and can possibly predict component failure. They also allow for secure calculation of results and automatic charting for routine trend analysis. Initially, data recording at our centre was paper-based for daily, weekly and monthly checks. This paper system has been successfully replaced with an electronic system for QC data recording and processing for linear accelerators and superficial units. The system makes use of personal digital assistants and networked laptops for online recording of data, and networked desktop PCs for offline work. The systems of data recording have been designed using the power of macros within Microsoft Excel, which automatically calculate each QC parameter and charts the data recorded for long-term analysis of trends. As of the beginning of 2006, these systems have been fully implemented. The benefits of implementing such a system are numerous, for example, central storage, backup and archiving of data, for greater security and reducing operator errors in calculations. Other benefits are discussed within the paper. In the future, we hope to develop similar systems of data recording for QC checks on other radiotherapy equipment.

Computers, Handheld↗
PubMed1999

Setting the standards: quality control in the secretory pathway.

A variety of quality control mechanisms operate in the endoplasmic reticulum and in downstream compartments of the secretory pathway to ensure the fidelity and regulation of protein expression during cell life and differentiation. As a rule, only proteins that pass a stringent selection process are transported to their target organelles and compartments. If proper maturation fails, the aberrant products are degraded. Quality control improves folding efficiency by retaining proteins in the special folding environment of the endoplasmic reticulum, and it prevents harmful effects that could be caused by the deployment of incompletely folded or assembled proteins.

Animals↗