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PubMed2005

[Reference materials for quality control of water analysis].

The ability to carry out analytical determinations meeting the needs which have prompted them is the first priority of a laboratory independent of its specific area of competence. In this framework the key concepts inspiring the quality management of a laboratory are discussed with particular emphasis on the quantification of analytes in water, the availability to this end of certified and work reference materials, their use for the quality control of measurements and the participation in proficiency testing for quality assurance and sampling procedures. A laboratory managed in conformity with such criteria allows analytical methods to be validated and generates valid, defensible and comparable experimental information on the qualitative and quantitative presence of organic and inorganic substances in water.

Accreditation↗

PubMed1983

Contemporary quality control practices for antimicrobial susceptibility tests: a report from the microbiology portion of the College of American Pathologists (CAP) surveys program.

The evaluation of quality control (QC) practices from the College of American Pathologists (CAP) Microbiology Surveys demonstrates a trend away from daily controls similar to that first noted in 1980. Previous recommendations for more relevant cost-containment oriented weekly QC procedures are discussed, and the 1982 CAP Surveys statistics confirm earlier comparability between the daily and weekly QC participant groups. Each QC practice subgroup (daily or weekly) had nearly identical mean disk inhibitory zone diameters, and the performance accuracy on two 1982 challenge strains were very similar. Generally, disk zone diameter from those laboratories using weekly QC were smaller, but the frequency of minor and major (false-resistant) errors was only slightly increased. The authors recommend the conversion to weekly QC of disk or dilution antimicrobial susceptibility tests after an acceptable daily QC performance has been established (See criteria in discussion).

Drug Resistance, Microbial↗

PubMed1998

[Identification of alloantibodies associated with an autoantibody: profile of 2 quality control programs in French blood transfusion facilities].

The French Blood Transfusion Society working group Immunohaematology and the French Blood Transfusion Center of Lille performed two quality control exercises-96-01 and 97-02-in order to evaluate identification performances of alloantibodies associated with an autoantibody recognizing a high frequency antigen. Concerning control 96-01, 83 (75%) of the 110 blood transfusion centers participating at this exercise sent results. The alloantibody screening was correct for 78 of them (94%). Sixty-one (78%) blood transfusion centers correctly identified the specificities (anti-RH1 + anti-FY1). Concerning control 97-02, 82 (94%) of the 87 blood transfusion centers participating in this exercise sent results. The alloantibody screening was correct for 69 (88%) of them. Fifty-three blood transfusion centers (77%) correctly identified the specificities (anti-RH3 + anti-FY1). These exercises allowed us to confirm the main procedures used in routine for national scale testing. The analysis of the results has underlined the importance of these tests for assessing the quality of these examinations, and highlighted the means to be carried out in order to improve them.

Antibodies, Anti-Idiotypic↗

PubMedDate not supplied

Quality control in diagnostic radiology at Mayo Clinic.

During the past five years in the department of diagnostic radiology at Mayo Clinic, a quantitative quality control program has been developed and expanded. Its goal is to assure consistent image quality while minimizing exposure to radiation and reducing costs wherever possible. The key to the program is the collection of quantitative data, ie, each parameter is evaluated by an objective, not a subjective, measure which is accurate and repeatable even if the measurement is made by various persons. Operating levels and control limits have been established for all measurements, with the control limits set so changes are quantitatively noted before changes occur in the images presented to the diagnostic radiologists.

Hospital Departments↗

PubMed1997

Quality control study of the Italian Group of Cytometry on flow cytometry DNA content measurements: II. Factors affecting inter- and intralaboratory variability.

A multicentric national quality control study has been organized under the auspices of the Italian Group of Cytometry to find a possible influence of some procedural steps in DNA flow cytometry measurements on DNA index (DI) values and to identify the main parameters affecting the interlaboratory variability. To 40 participating laboratories we provided suspensions containing unknown mixture of different cell types: an homogeneous thymocyte population used to check instrument linearity; one mixture composed of two cell types characterized by DI = 1.00 and 1.10; and another composed of three different cell types with relative DIs of 1.00, 1.26, and 1.62, respectively. Possible effects due to staining protocols were studied, allowing the participants to stain cellular DNA according to the procedure routinely adopted in each laboratory, in addition to a standardized procedure with a fixed PI solution. As far as the influence of instrument linearity on DI values is concerned, we did not find any correlation with the DI variability observed, even if the use of a standardized staining protocol could lead to a sensible gain in interlaboratory DI reproducibility. Twenty-five of 40 (65%) laboratories were able to discriminate the near-diploid subpopulation, and a coefficient of variation of less than 4% was the minimum condition necessary to recognize the DI = 1.1 population. In samples containing two aneuploid subpopulations, 25 of 35 (71.4%) laboratories showed a high reproducibility with the standard staining protocol and 22 of 38 (57.9%) with the free staining protocol. However, a sensible improvement in interlaboratory reproducibility emerged with respect to the previous trial.

Animals↗

PubMed1993

Chorionic villus sampling: quality control--a continuous improvement model.

OBJECTIVE: Our purpose was to describe Vanderbilt University Medical Center's experience in establishing a chorionic villus sampling program and the importance of quality control along with a continuous improvement model on the first 1000 cases. STUDY DESIGN: A continuous improvement model was established with emphasis on a multidisciplinary team approach and quality assurance process. A computerized data base was used for continuing analysis of complications and for allowing facile access to pertinent information. RESULTS: A continuous improvement model allowed for an improved process and outcome for patients, personnel, and referring health care providers. Follow-up for initial symptoms after chorionic villus sampling was obtained on 98.5% of patients. Pregnancy follow-up, including birth data, was obtained on 93%. CONCLUSION: A continuous improvement mode from the project's onset resulted in an improved process and outcome, information helpful for accessing spontaneous abortion rates and pregnancy outcomes (including the incidence of limb abnormalities and factors associated with abortions) and recommendations for training personnel.

Abortion, Spontaneous↗

PubMed2001

[Preparation and quality control of cross-linked agarose coated activated charcoal (CAAC-II) used as adsorbents for hemoperfusion in artificial liver support].

The preparation and the quality control of cross-linked agarose coated activated (CAAC-II) were described. The crosslinking reagent epichlorohydrin was removed. Investigations indicate that the trace elements such as Pb, Cd, As, Cr, Fe and heavy metals, the pH, NH4+, SO4(2-), and ultraviolet absorbance in sample have met the requirements in Chinese Pharmacopeia and some other relevant standard promulgated by the Ministry of Health. No epichlorohydrin was detected in CAAC-II.

Capsules↗

PubMed2002

[The medical gas central supply system and its quality control].

This paper introduces the principles of the medical gas central supply system and its structure, Classification, standards, flow chart and its advantages, and its quantity guarantee and quality control.

Equipment Design↗

PubMed2004

A new quality control method based on a moving average of "latent reference values" selected from patients' daily test results.

The average of normals(AON) method is a quality control(QC) method that uses measured values of patients' samples instead of QC samples. Because this method is easily affected by fluctuations in the patient population and is insensitive to short-term changes in test values, we developed an alternative method based on the moving average(MA) of latent reference values(LRVs) which are the test results of patients whose other related test results are all within reference intervals. We evaluate the new methodology(MALRV) using seven commonly measured biochemical tests. The LRV of each test were selected with reference to four other items that had the highest coincidences of abnormality. The optimum amount of data needed to compute the MA is determined as that making the coefficient of variation(CV) of the consecutive MA over a study period less than 5.0%. The MALRV is computed each time a new LRV is encountered to monitor quality status continuously. The MALRV CV was within 5.0% when sample sizes were between 20 and 110. When shift and trend simulations were performed with the patient data, the corresponding alterations were detected. MALRV is a useful measure for detecting short-term alterations in patient test results, supplementing the conventional QC chart method.

Clinical Laboratory Techniques↗

PubMed2004

Disk diffusion quality control guidelines for NVP-PDF 713: a novel peptide deformylase inhibitor.

NVP-PDF713 is a peptide deformylase inhibitor that has emerged as a candidate for treating Gram-positive infections and selected Gram-negative species that commonly cause community-acquired respiratory tract infections. This report summarizes the results of a multi-center (seven participants) disk diffusion quality control (QC) investigation for NVP PDF-713 using guidelines of the National Committee for Clinical Laboratory Standards and the standardized disk diffusion method. A total of 420 NVP-PDF 713 zone diameter values were generated for each QC organism. The proposed zone diameter ranges contained 97.6-99.8% of the reported participant results and were: Staphylococcus aureus ATCC 25923 (25-35 mm), Streptococcus pneumoniae ATCC 49619 (30-37 mm), and Haemophilus influenzae ATCC 49247 (24-32 mm). These QC criteria for the disk diffusion method should be applied during the NVP-PDF 713 clinical trials to maximize test accuracy.

Amidohydrolases↗

PubMed2003

Headspace solid-phase microextraction-gas chromatography-mass spectrometry applied to quality control in multilayer-packaging manufacture.

A method based on headspace solid-phase microextraction-gas chromatography-mass spectrometry is proposed for the quality control of multilayer packaging and its manufacturing process. Volatile organic compounds (VOCs) are produced in the manufacturing process of the packaging. They can cause organoleptic problems or modify the properties of the packaging depending on the nature and the amount of the VOCs formed. The quantification using packaging samples with a known VOC concentration for the calibration is proposed in order to reduce the analysis time, and the method is validated using a statistical test. Finally, the method is applied to the determination of odour-responsible compounds in multilayer packaging samples obtained under different extrusion-coating conditions, i.e. type of extruder, type of polymer and extrusion speed.

Calibration↗

PubMed1996

Replacement, reduction or refinement of animal use in the quality control of veterinary vaccines: development, validation and implementation.

Various different methods have been developed to replace, reduce or refine the use of animals in batch quality control tests of veterinary vaccines. The development, validation and implementation of those alternatives which lead to a significant reduction in the numbers or the suffering of the animals used must receive priority. Validation is one of the hurdles to the implementation of alternative methods into relevant legislation, so it deserves special attention. For proper validation studies, co-operation between various organisations of both government and industry is necessary. International and national organisations such as ECVAM, FRAME, SIATT, ZEBET and the recently established Netherlands Centre Alternatives to Animal Use (NCA) could contribute significantly to the development, validation and implementation of alternative methods by simulating and co-ordinating research projects, by providing information through databases, and by co-ordinating validation studies.

Animal Testing Alternatives↗

PubMed1988

An optimized quality control procedure for hematology analyzers with the use of retained patient specimens.

The authors propose guidelines for the use of retained patient specimens for the quality control of multichannel hematology analyzers. They demonstrate that control limits for patient specimen replicates may be derived from the long-term standard deviations (s) of commercial whole blood controls. They then use computer stimulation of the Coulter multichannel hematology instrument to determine power functions of various procedures using retained specimens. These power functions show that the use of three patient specimens and +/- 2 s limits are optimal for the detection of systematic error. They recommend that three different, previously analyzed normal range specimens be periodically analyzed, e.g., at eight-hour intervals. The differences between the current and original measurements should then be calculated and compared with their +/- 2 s limits. If at least two of the three differences for any directly measured parameter exceed the +/- 2 s limits, there will be a high probability of significant analytic error. Because the power functions of the derived red blood cell parameters, hematocrit, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration demonstrate relatively low error detection capabilities, the authors recommend that these parameters not be monitored with the retained patient specimen procedure.

Hematology↗

PubMed1992

Studies on the quality control of stroma-free hemoglobin.

Analytical methods for phospholipids and blood group antigen were developed using HPLC-UV and EIA, respectively, for the quality control of SFH. These methods had sensitivities superior to those of conventional assays. In addition, the HPLC method could isolate PS, which might play an essential role in blood coagulation. The above analytical methods were applied to evaluate three representatives SFH preparation methods, 36,000xg centrifugation followed by the filtration with a 0.22 um filter, ultrafiltration with a 100 kd membrane, and filtration with the BMM-40 nm membrane. Both the BMM method and the ultrafiltration method were shown to remove more than 99.7% of phospholipids, and more than 99.99% of blood group antigen. On the other hand, the centrifugation preparation still contained much of both components. The BMM filter was originally developed as a virus removal filter. The virus removal efficiency of the BMM-40 nm was examined with a genetic technique, the PCR method. The BMM-40 nm was demonstrated to remove HB viruses with an efficiency of eight log or more. These results indicate that the BMM is a useful filter to prepare a stroma-free, virus-reduced hemoglobin solution.

Antigens↗

PubMedDate not supplied

[Quality control of total parenteral nutrition in the 1991-1992 biennium].

OBJECTIVE: To assess the degree of compliance with standards defined for Total Parenteral Nutrition (TPN) quality control in our hospital in the two-year period 1991-1992. MATERIAL AND METHODS: All available information was assessed concerning 52 patients (32 men and 17 women) for whom a TPN course was prescribed in relation with certain pre-set indications. These patients received a total of 1140 TPN units with the TPN lasting an average of 21.9 days (range, 1-73 days). Monitoring was done by the Nutrition and Diet Section. The degree of compliance was assessed with the standards model proposed by the Providence Medical Center, Portland (USA) (PMCP) with 24 parameters (PM): indications, initiation in the first 24 hours, nutritional assessment in the first 24 hours, period of the TPN, metabolic complications (14 PM), septic complications (3 PM), nutritional consequences (2 PM) and TPN losses. All parameters were appraised and admitted, except for urea, which was corrected to standard values of our Laboratory (< 44 mg/dl), with Transferrin evaluation instead of iron binding capacity (TIBC), taking as compliance standard a figure of > 190 mg/dl. All analytical calculations were carried out in our Central Laboratory Service. RESULTS: Of all the parameters, the following were discarded, not being calculated on a routine basis: total CO2, serous magnesium, urinary uric nitrogen, nitrogen balance, positive hemocultures, catheters and TPN losses. Levels of compliance varied between 31.9% and 100%, with 8 parameters within the standards (Initiation, 100%; evaluation in first 24 hours, 100%; extent, 100%; creatinine, 100%; total bilirubin, 92.2%; cholesterol, 99.5%; transferrin, 35.9%). Seven parameters fell short (Na, 88.1%; K, 92.9%; Cl, 89.3%; Urea, 54.4%; Glucose, 96.4%; P, 94.1%; Triglycerides, 71.9%). CONCLUSIONS: We infer from our study that there is a need to make use of a large part of the indicators described in the literature as indicators for quality guarantee of a TPN program, and the use of new parameters must be assessed in normal monitoring.

Adolescent↗

PubMed1999

Accuracy in naturally occurring anabolic steroid assays in cattle and first approach to quality control in Italy.

This study assessed the accuracy of 16 commercial and three self-produced kits and drew the basis for using an external quality control (EQC) system. The commercial kits were mainly developed for blood sex steroid determination in humans but also have been used in cattle. Parallelism, recovery and precision tests were performed for progesterone (P4), testosterone (T) and oestradiol (E2) assays. Moreover, anonymous QC samples were sent to be analysed to some Italian laboratories. All kits showed a fair degree of parallelism (P < 0.01), even though 2/7 kits for T and 1/6 kits for E2 determination showed a regression coefficient (r2) lower than 0.98. For P4, an acceptable range of accuracy was achieved in the recovery test only by 1/6 kits; two kits showed fair or great overestimation and two kits considerable underestimation. For T, an acceptable range of accuracy was achieved only by 1/7 kits. For E2, 4/6 kits presented a variable degree of underestimation and two kits showed great overestimation. In the intra-assay precision test quite good repeatability was achieved only using samples with high hormone concentrations. While assaying samples with low concentrations we found a number of RSD > 10%. Moreover, the laboratories participating in the EQC produced statistically different (P < 0.05) results, particularly for high and medium concentrations. In conclusion, the use of commercial kits for screening naturally occurring sex steroid concentrations in cattle blood, in the case of suspected illegal treatments, requires preventive validation procedures and the development of an opportune EQC system.

Anabolic Agents↗

PubMed1990

[Log book registration of farms for slaughtering pigs in the Integrated Quality Control Project. I. Use of drugs and vaccines].

Log book recording was done for twelve months on approximately 100 pig finishing farms in an Integrated Quality Control (IQC) project. This recording was designed to gain a better understanding of the extent and nature of the medication and vaccination on these farms. Vaccination against Aujeszky's disease was done on the majority of farms. This vaccination mainly consisted in a single, frequently intramuscular, injection. Vaccinations against swine influenza and infections due to Actinobacillus (Haemophilus) pleuropneumoniae were merely sporadic. The animals were dewormed in 58 per cent of the finishing periods, whereas they were given preventive treatment for sarcoptic mange in 23 per cent of the finishing periods. Not a single pig was treated with antibiotics and/or chemotherapeutic agents in 12.5 per cent of the finishing periods. The majority of finishing periods in which treatment was not carried out, were those having closed pig herds. To the extent that the farms were supplied with piglets by more breeders, there were fewer finishing periods during which treatment was omitted. The great majority of cases in which individual therapy was given, were treated for respiratory disorders. On 27 per cent of the farms, more than 10 per cent of the animals per finishing period were treated for respiratory disorders. Group medication was much less frequent: intestinal disorders did not have to be treated on 31 per cent of the farms, and 16 per cent did not require treatment for respiratory disorders. In the great majority of cases in which group treatment was required, this was given during the first sixty days of the finishing period. In view of the fact that there are marked differences in the degree to which pigs have to be medicated on the farms, recording the use of veterinary drugs on farms, could fulfil the function of a signal. On the basis of these signals, measures may be suggested in herd management programmes to ensure an effective and minimum use of veterinary drugs. Using a log book will also enable the pig farmer to estimate whether groups of animals may be sent to the slaughter-house without involving risks to public health.

Animal Husbandry↗

PubMed1989

The questionnaire--a quality control method for online searching?

The quality of the online search service in a university medical school/large hospital library was investigated by user survey. The use of a questionnaire as a tool to measure quality was assessed. The survey indicated that most users were satisfied with the quality of the service. User ratings for all search performance criteria were high and most readers found online searches to be good value for money. Information about user groups, frequency of searching, search applications, pre-search work and user expectations was obtained. The most important aspect of a computer search to the reader was 'savings in your time'. Three types of user were described based on search output analyses and reading levels. Some areas where the existing service could be improved were identified. The introduction of a standard questionnaire for monitoring the quality of computer searches and other library services was proposed.

Consumer Behavior↗