Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “quality control”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources
PubMed1977

Improved quality control of blood acid-base equilibrium using the daily mean of patients' results: a validation study.

The efficiency of the daily mean of patients' results as a quality control tool for acid-base equilibrium has been studied in three one-month periods. Results for the first two periods were obtained in a stable patient population using tonometry in one period, direct measurement of PCO2 in the other; the third period corresponded to another patient population in which PCO2 was determined by direct measurement. These comparisons allowed demonstration that both methodology and patient populations influenced the optimal truncation limits used to exclude extreme values. Furthermore, the efficiency of the daily mean in itself was poor. Using a cusum plot of the differences of each daily mean from the monthly mean of the daily means, however, dramatically improved this efficiency. So modified, quality control using the daily mean of patients' results represents a useful tool, since the whole analytic process, from blood sampling to result, is checked.

Acid-Base Equilibrium↗
PubMed1983

Disk agar diffusion susceptibility testing with 30-micrograms ceftazidime disks: confirmation of interpretive breakpoints and quality control guidelines.

Ceftazidime is a wide-spectrum, beta-lactamase-stable cephalosporin with remarkable potency against Pseudomonas spp., Enterobacteriaceae, and some gram-positive species. The reevaluation of the 30-micrograms ceftazidime disk diffusion tests with commercially prepared disks confirms the proposed susceptibility breakpoint zone of greater than or equal to 17 mm (minimal inhibitory concentration correlate, less than or equal to 8.0 micrograms/ml) and the resistance breakpoint zone of less than or equal to 13 mm (minimal inhibitory concentration correlate, greater than or equal to 32 micrograms/ml). Major and minor interpretive errors were only 4.4%, and these errors could be further reduced to 1.1% by not testing gram-positive organisms, particularly enterococci and Staphylococcus spp. On the basis of the results from a multilaboratory quality control study, the following zone diameter quality control guidelines are suggested: Escherichia coli ATCC 25922, 27 to 31 mm; Staphylococcus aureus, ATCC 25923, 16 to 20 mm; Pseudomonas aeruginosa ATCC 27853, 24 to 28 mm.

Agar↗
PubMed1996

A three-center European external quality control study of PCR for detection of cytomegalovirus DNA in blood.

The presence of cytomegalovirus (CMV) in the blood has important consequences for patient management, and an external quality control study of its detection by the PCR was conducted by the Infectious Disease Working Party of the European Group for Blood and Marrow Transplantation. Forty-eight coded peripheral blood samples from bone marrow transplant recipients were processed in parallel in three European centers by using the routine in-house PCR assay. Protocols varied in choice of primers, specificity and amplificability controls, and sample processing. Results for 38 of 47 samples agreed, 35 being negative and 3 positive. Of the 12 samples reported as positive by a least one center, only 3 were found to be positive by all three centers, 1 was found to be positive by two centers, and the remaining 8 were found to be positive by one center only. The nine discrepant samples appeared to contain around 1,000-fold less viral DNA than the three concordant positive samples. CMV detection was affected both by the number of leukocytes from which DNA was extracted and by the number of cell equivalents added per PCR. External quality control schemes for CMV PCR are clearly necessary in order to compare data from different centers, and recommendation for standardizing the PCR detection of CMV in blood leukocytes are made.

Bone Marrow Transplantation↗
PubMed2006

[Quality control of hospital preparations: results concerning capsules production in a child hospital].

In France, lack of paediatric drugs leads pharmacies to produce many hospital preparations in order to meet prescribers'needs. To ensure the quality of these preparations, the pharmacy department of the Armand Trousseau Child Hospital set up a quality control system of its capsules. It integrates both European Pharmacopeia's requirements (Mass and Content uniformity test) and more strict internal quality specifications. They include exactitude of the average content compared to the awaited content, coefficient of variation of the contents and, "modified" content uniformity test. These criteria and the percentage of nonconformity are used as indicators to assure quality follow-up of the preparations. We reviewed quality control records for five hospital preparations produced over the last three years. We highlighted that lower dosage showed a higher percentage of nonconformity compared to higher dosage. Type of active ingredients was a key factors too (1,0% and 14.8% of non conform batches for ursodesoxycholic acid and for morphine hydrochloride respectively). Analysis showed that the essential character of content test because mass test is not predictive of the conformity of the batch. Content test was the main criterion to judge batches conformity. Thus, it will be generalized to all our preparations. These study results helped us to implement new procedures to assure an ongoing improvement of our practices of preparation.

Capsules↗
PubMed2002

Quality control assessment of influenza and RSV testing in Europe: 2000-01 season.

The Quality Control Assessment (QCA) was initiated to evaluate the quality of the influenza and respiratory syncytial virus (RSV) testing in the national reference centres belonging to the European Influenza Surveillance Scheme (EISS) network. Samples were coded and sent in two panels of 12 samples within a two week interval to 16 laboratories during the 2000-01 winter season. The antibodies titration by HI test was reported by 60% of the laboratories (n=16), and the results were correct for 56% of them. One false detection of influenza B antibodies was reported by one laboratory, and for the others the sensitivity varied widely. The sensitivity of the tests for the detection of influenza virus varied for A(H3N2) from 10 to 100,000 TCID50/ml. The influenza A subtyping was performed by 87% of the laboratories, and 31% gave correct results. The characterisation of the variants was undertaken by six laboratories and half of them fully achieved it. Fifty six percent of the laboratories used RT-PCR for the diagnosis; the results were specific and the sensitivity equivalent to the cell culture.

Antigens, Viral↗
PubMed1998

Internal quality control of the malaria microscopy diagnosis for 10 laboratories on the Thai-Myanmar border.

On the Thai-Myanmar border, where multidrug resistance to anti-malaria medications is a major problem, a quality control program for diagnostic laboratories has been set up. This study examines the "passive" screening performed in 10 laboratories. Monthly evaluation of the quality of thick and thin smear practice, Giemsa staining and microscopy took place during the year 1994. Considering the general context and the methodology applied, the evaluation of performance and strategy of the malaria diagnostic test showed satisfactory results for all 10 laboratories. Performance of technics = 64% (62-66) to 96% (95-97); Sensitivity = 92.6 (91.5-95.5) to 96.6% (95.8-99.0); Specificity = 93.5% (91.4-95.5) to 98.3% (97.6-99.0); Predictive Positive Value = 92.0% (90.9-93.1) to 98.3% (97.6-99.0); Predictive Negative Value = 94.3% (93.0-95.6) to 98.5% (98.0-99.0). The study underlines the importance of a reliable quality control method for microscopy diagnosis of malaria in hyperendemic areas, with Plasmodium falciparum as the main species. A high level of input from the international laboratory technician, performing training, follow-up and evaluation was required. The need for adequate training of national technicians and supervisors, especially regarding long-term sustainability, is stressed. The type of program presented can be used as a model for similar projects in developing countries.

Clinical Laboratory Techniques↗
PubMed2005

Fluorescence detection combined with either HPLC or HPTLC for pharmaceutical quality control in a hospital chemotherapy production unit: application to camptothecin derivatives.

In order to achieve the analytical assessment of the manufactured batches of chemotherapy preparations, post-production quality control has been developed. The common use of camptothecin derivatives (i.e. irinotecan (CPT-11) and topotecan (TPT)) as part of protocols in Institut Gustave Roussy (IGR) has led to develop an efficient analytical method that could assess an increasing number of samples with high throughput, good specificity and practicality. Due to the difference of concentration between batches containing irinotecan or topotecan, HPLC and HPTLC both combined with fluorescence detection were investigated. Those two techniques made identity, purity and quantitation assays possible. The chromatographic conditions that were chosen allowed identification of each drug through their rate of flow (Rf), 0.10 and 0.35, or their retention time (tR), 2 and 7 min for topotecan and irinotecan, respectively. A calibration curve was plotted for each molecule and validated by three quality controls (high, medium and low). Coefficients of variation of repeatability (CVr) and intermediate precision (CVi) were determined for both methods. Considering their values and the concentration ranges (from 100 to 500 mg/L for HPTLC and from 0.1 to 1 mg/L for HPLC), it was decided to perform analysis using HPTLC for irinotecan preparations and HPLC for topotecan preparations. These inferences seemed appropriate regarding the number of preparations to be assayed.

Antineoplastic Agents↗
PubMed1992

Achieving the Health Care Financing Administration limits by quality improvement and quality control. A real-world example.

With the enactment of the Clinical Laboratory Improvement Amendments of 1988 (CLIA 88), the federal government is now using proficiency testing as the primary indicator of laboratory quality. Laboratories with proficiency test failures are now at risk of a variety of harsh penalties including large monetary fines and suspension of operations. To minimize the risk of failed proficiency testing, we initiated a continuous quality improvement program in our general chemistry laboratory in conjunction with the use of a new survey-validated quality control product. This article describes the quality improvement program and our success in reducing the long-term random error in general chemistry. Despite our improvement program, significant analytical errors (greater than 30% of the CLIA limits) still exist in analytes measured by our chemistry analyzer. These errors are present in nearly the same analytes measured by other common chemistry analyzers indicating the need for improvement in their design and manufacture.

Blood Chemical Analysis↗
PubMed2004

Conserved ERAD-like quality control of a plant polytopic membrane protein.

The endoplasmic reticulum (ER) of eukaryotic cells serves as a checkpoint tightly monitoring protein integrity and channeling malformed proteins into different rescue and degradation routes. The degradation of several ER lumenal and membrane-localized proteins is mediated by ER-associated protein degradation (ERAD) in yeast (Saccharomyces cerevisiae) and mammalian cells. To date, evidence for the existence of ERAD-like mechanisms in plants is indirect and based on heterologous or artificial substrate proteins. Here, we show that an allelic series of single amino acid substitution mutants of the plant-specific barley (Hordeum vulgare) seven-transmembrane domain mildew resistance o (MLO) protein generates substrates for a postinsertional quality control process in plant, yeast, and human cells, suggesting conservation of the underlying mechanism across kingdoms. Specific stabilization of mutant MLO proteins in yeast strains carrying defined defects in protein quality control demonstrates that MLO degradation is mediated by HRD pathway-dependent ERAD. In plants, individual aberrant MLO proteins exhibit markedly reduced half-lives, are polyubiquitinated, and can be stabilized through inhibition of proteasome activity. This and a dependence on homologs of the AAA ATPase CDC48/p97 to eliminate the aberrant variants strongly suggest that MLO proteins are endogenous substrates of an ERAD-related plant quality control mechanism.

Amino Acid Substitution↗
PubMedDate not supplied

Intraoperative evaluation of laparoscopic insufflation technique for quality control in the OR.

OBJECTIVE: With increasing technology and computerized systems in the OR, the physician's responsibility is growing. For intraoperative evaluation of insufflation techniques, a data acquisition model for quality control study of potential insufflation problems is necessary. METHODS: A computer-based, online data acquisition model was designed with a Pentium notebook, PCMCIA data acquisition board PCI-460-P1 and a Visual Designer 3.0 measurement program (both Intelligent Instrumentation, Inc., Tucson, AZ), temperature meters Therm 2280-1 and 2283-2 (Ahlborn, Holzkirchen, Germany) and temperature probes 401 AC and 402 AC (YSI, Inc., Yellow Springs, OH) and T-430-2R (Ahlborn, Holzkirchen, Germany). Gas flow was measured with laminar flow element LFE 1 and flow meters Digima premo 720 (both Special Instruments, Noerdlingen, Germany). During 73 standard laparoscopic procedures, gas flow (L/min) in the insufflation hose, pressure (mm Hg) in the hose and abdomen as well as temperature (degrees C) in the hose, abdomen and rectum were measured continuously at 3 Hz rate. RESULTS: Actual values measured show a wide range often not identical with insufflator presetting. Pressure in the abdomen is usually less than hose pressure. Intra-abdominal pressure peaks (< or = 50 mm Hg) occurred during insufficient anesthesia, while leaning on the abdomen, during trocar insertion and other manipulation. Blood-irrigation fluids found in the hose (n=3/73) can lead to bacterial contamination. Negative pressure (-50 mm Hg) was measured due to Endobag removal. Negative flow (< or = 15 L/min) was caused by pressure on the abdomen, insufflator regulation and an empty CO2 gas tank. Gas temperature in the hose equals room temperature but can decrease in the abdomen to 27.7 degrees C due to high gas flow, large amounts of gas used and prolonged insufflation. Further insufflation-related problems were documented. CONCLUSIONS: This computer-based measurement model proved to be useful for quality control study in the OR. Results demonstrate the need for intraoperative evaluation of insufflation techniques for laparoscopy. Although no obvious complication related to insufflation problems occurred, some findings potentially question patient security.

Computer Graphics↗
PubMed2003

Using mobile information technology to build a database for anesthesia quality control and to provide clinical guidelines.

The paper describes a mobile information system to collect patient information for anaesthesia quality control. In this system we use handheld computers, to collect patient data at the bedside with a daily synchronization of the data of the anaesthesiologist's handheld with the anaesthesia database center, later used for quality control analysis. Further, we design mobile clinical guidelines to be used on the same handhelds.

Anesthesia↗
PubMed1992

Sperm hyperactivation as quality control for sperm penetration assay.

The sperm penetration assay (SPA) is subject to considerable variation, and controls are needed to verify the accuracy of the results. It is proposed that sperm hyperactivation (HA) can serve as a quality control check for the SPA. The objective was to determine if there was an association between the SPA outcome and sperm HA measured at various times during the SPA procedure. The data showed a significant correlation between percent sperm HA and percent zona-free oocyte penetration by sperm preincubated for three hours prior to sperm-oocyte interaction (short preincubation). Some sperm hyperactivity was observed in liquefied raw semen samples, but this was insignificantly related to SPA results. Low correlation was observed between SPA results and sperm HA determined immediately after centrifuge washing of sperm. The results suggest that it is possible to utilize sperm HA measured immediately after the sperm-oocyte interaction period as a quality control check of SPA results.

Female↗
PubMed1991

The quality control of cell banks using DNA fingerprinting.

Reproducibility in animal cell culture technology requires careful preparation and characterisation of banks of cell cultures. The two standard techniques used in the quality control of such banks are isoenzyme analysis and cytogenetics which require complex and time-consuming procedures to enable cell line identification. However, DNA fingerprinting is potentially a more powerful method of analysis which can detect mutation and intra-species cross-contamination. At the European Collection of Animal Cell Cultures (ECACC) multilocus fingerprint analysis using probes 33.6 and 33.15 has been assessed in the quality control of cell banks. This method has confirmed consistency between master and working banks, has proven useful over a wide species range and can differentiate closely related cell lines. The key advantage of this method is its ability to detect cross-contamination by cell lines from a wide range of species using a straightforward and economical test. In addition the reproducibility of DNA fingerprints indicates their possible role in cell line authentication procedures which are important for patent and product licence applications.

Animals↗
PubMed2000

Daptomycin susceptibility tests: interpretive criteria, quality control, and effect of calcium on in vitro tests.

Daptomycin MICs were determined for 844 Gram-positive bacteria in three concentrations of Ca(++) and compared with the MICs of vancomycin and teicoplanin. Daptomycin was twofold to fourfold more active against most species when tested in 50 microg/ml of Ca(++) than in 25 microg/ml. In 50 microg/ml of Ca(++) daptomycin was more active against methicillin-resistant staphylococci and vancomycin-resistant enterococci than teicoplanin or vancomycin; 100% of these isolates were susceptible to < or =2.0 microg/ml of daptomycin. Different lots of Mueller-Hinton agar were variable in Ca(++) content, and daptomycin disk diffusion zone diameters were affected, i.e., zones were 1 to 15 mm smaller on one lot of agar with only 6 microg/ml of Ca(++) compared to another lot with 28 microg/ml. The previously proposed daptomycin interpretive breakpoints performed satisfactorily when MICs were determined in Mueller-Hinton broth with 50 microg/ml of Ca(++) and when the agar gave appropriate zones with quality control strains. To define those control limits, replicate tests with four quality control strains were performed in ten laboratories using broth microdilution tests (with Ca(++) supplemented broth) and disk diffusion tests on Mueller-Hinton agar without cation adjustments.

Anti-Bacterial Agents↗
PubMed1992

Limited adverse occurrence screening. A medical quality control system for medium sized hospitals.

OBJECTIVE: To determine whether adverse occurrence screening of inpatient discharge summaries by means of a limited number of criteria can provide an effective medical quality control system without requiring substantial additional resources. DESIGN: The medical records department used 14 criteria to screen all inpatient discharge summaries shortly after discharge. Summaries that met particular criteria were sent for medical review. If an adverse patient event was found, appropriate action was determined by a committee of four doctors. SETTING: 200 bed base hospital in country Victoria. PATIENTS: All inpatients discharged over a two year period. MAIN OUTCOME MEASURES: The incidence of negative patient outcomes and the cost of resources required to conduct the program. RESULTS: A reduction in the incidence of some negative patient outcomes was achieved and the nature of postgraduate education meetings was changed. Minimal additional resources were required to run the program. CONCLUSION: Limited adverse occurrence screening has provided a simple, inexpensive and effective medical quality control system in a medium-sized hospital.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

[Study on HPLC fingerprint and quality control of Propolis].

OBJECTIVE: To study on HPLC fingerprint of Propolis and to control it's quality. METHOD: The chromatographic fingerprints of seven samples from different producing areas were determined by RP-HPLC. RESULT: The chromatograms of Propolis from different producing areas were very similar. CONCLUSION: The quality of Propolis can be controlled by determination the HPLC fingerprint.

Chromatography, High Pressure Liquid↗
PubMed1988

Blood gas quality control materials compared to tonometered blood in examining for interinstrument bias in PO2.

Although large differences in mean values and standard deviations of PO2 between models of blood gas instruments have been found in proficiency testing surveys employing commercial ampuled material, it is unknown whether or not equivalent differences would be found between instruments if a primary standard (tonometered fresh human blood) were used instead of ampules (secondary control specimens). Therefore, we compared the biases (differences between means) of six models of blood gas instruments using five varieties of ampuled quality control materials and a single source of tonometered fresh human blood at three levels of PO2 (67.5, 91.4, and 143.6 mm Hg). All materials correlated positively with blood, thus demonstrating consistency of machine biases. The coefficients of variation measuring blood and a perfluorocarbon mixture (abc) were not different, but were higher for aqueous and hemoglobin-containing mixtures. On average, at the PO2 levels tested, the differences among instruments were slightly smaller with abc than with blood, but larger with aqueous and hemoglobin-containing materials. Because abc "tracks" tonometered blood reasonably well at the PO2 levels tested, instrument differences in PO2 detected with abc are also likely to be seen with clinical blood samples. The other four quality control materials probably overestimate instrument differences in measuring PO2.

Blood Gas Analysis↗