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PubMed1996

Proposed MIC quality control guidelines for National Committee for Clinical Laboratory Standards susceptibility tests using seven veterinary antimicrobial agents: ceftiofur, enrofloxacin, florfenicol, penicillin G-novobiocin, pirlimycin, premafloxacin, and spectinomycin.

The present multicenter study proposes broth microdilution quality control (QC) ranges for the antimicrobial agents ceftiofur, enrofloxacin, florfenicol, penicillin G-novobiocin, pirlimycin, premafloxacin, and spectinomycin, which are used in veterinary practice. Six separate laboratories tested replicates of National Committee for Clinical Laboratory Standards (NCCLS)-recommended QC organisms (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) on medium lots both common and unique to all laboratories. The proposed ranges were within 3 or 4 log2 dilution steps of the modal MICs for all organism-antimicrobial agent pairs, depending on their MIC distributions. With > or = 94.7% of all MIC results being within the proposed QC ranges, all combinations tested comply with NCCLS guidelines and all have been accepted by the NCCLS subcommittee developing susceptibility testing procedures for veterinary laboratories.

Anti-Bacterial Agents↗

PubMed1999

Comparison of three methods to assess therapeutic quality control of treatment with vitamin K antagonists.

During treatment with vitamin K antagonists, International Normalized Ratios (INR) are determined periodically to maintain a therapeutic level of anticoagulation. We evaluated two existing methods for therapeutic quality control (linear interpolation and equidivision), with regard to their validity and reproducibility. In addition, we proposed and evaluated a (hybrid) method that takes into account potential effects of dosage modifications when INRs are far out of the target range. Validity was assessed by deleting intermediary INR results and estimating this INR based on the two surrounding INRs with each of the three methods. The estimated INRs were then compared with the observed INR. Reproducibility of time spent in an INR range was evaluated for each of the three methods by deleting at random increasing proportions of INRs and comparing these estimates with the situation without deletions. We found that estimates of time spent in INR categories obtained with equidivision were most reproducible, but least valid. The hybrid method showed slightly higher validity and reproducibility in comparison with linear interpolation. Since these differences were small, linear interpolation is preferable to the hybrid method, since the calculations involved are easier.

Fibrinolytic Agents↗

PubMed2005

[Discussion on design and quality control of clinical trials of traditional Chinese medicine on the basis of Fuhuang Tablets clinical study].

OBJECTIVES: To assess the efficacy of Fuhuang Tablets in treating internal hemorrhoid hemorrhage and discussing the design and quality control of clinical trials of traditional Chinese medicine. METHODS: According to two-center, randomized, blinded and controlled study, 144 patients with internal hemorrhoids were divided into 2 groups. Seventy-two patients were treated with Fuhuang Tablets (4 tablets t.i.d. per os) and the other 72 patients were treated with Zhining Tablets (4 tablets t.i.d. per os). Symptoms and signs of the patients were recorded and evaluated at the third and seventh day of treatment respectively. RESULTS: At the third day of treatment, the overall response rates of Fuhuang Tablets-treated group and Zhining Tablets-treated group were 58.57% and 27.78% respectively, with statistic difference between the two groups (P<0.05). At the seventh day of treatment, the overall response rates of Fuhuang Tablets-treated group and Zhining Tablets-treated group were 91.43% and 81.94% respectively, with no statistic difference between the two groups. The laboratory test results and life signs of the 144 patients were normal before and after the treatment. CONCLUSION: Fuhuang Tablets are effective and safe in treating internal hemorrhoid hemorrhage.

Adolescent↗

PubMed1992

Toxic trace elements in Chilean seafoods: development of analytical quality control procedures.

Chile is a well known producer and exporter of shell fish. These seafoods, like other specimens of marine origin, are susceptible to environmental and other contamination by trace elements, including toxicants. Therefore, adequate analytical quality assurance is mandatory before accepting analytical results. In this context, the use of at least two independent methods of determination and validation with certified reference materials (CRM) provides acceptable criteria for judging the reliability of the data. This paper describes sample treatments and analytical procedures for Cd, Cu and Hg determinations in mollusc samples. Three independent analytical techniques, namely differential pulse anodic stripping voltammetry, neutron activation analysis and atomic absorption spectrometry, were used. CRM standards of the IAEA, NIST and BCR were analyzed to evaluate quality assurance. Following the quality control phase, the concentrations of cadmium, copper and mercury in fresh and canned mollusc samples Tagelus dombeii and Semelle solida (Navajuelas and Almejas chilenas respectively) from different locations were determined.

Chile↗

PubMed2002

Quality control of brachytherapy equipment in the Netherlands and Belgium: current practice and minimum requirements.

BACKGROUND AND PURPOSE: Brachytherapy is applied in 39 radiotherapy institutions in The Netherlands and Belgium. Each institution has its own quality control (QC) programme to ensure safe and accurate dose delivery to the patient. The main goal of this work is to gain insight into the current practice of QC of brachytherapy in The Netherlands and Belgium and to reduce possible variations in test frequencies and tolerances by formulating a set of minimum QC-requirements. MATERIALS AND METHODS: An extensive questionnaire about QC of brachytherapy was distributed to and completed by the 39 radiotherapy institutions. A separate smaller questionnaire was sent to nine institutions performing intracoronary brachytherapy. The questions were related to safety systems, physical irradiation parameters and total time spent on QC. The results of the questionnaires were compared with recommendations given in international brachytherapy QC reports. RESULTS: The answers to the questionnaires showed large variations in test frequencies and test methods. Furthermore, large variations in time spent on QC exist, which is mainly due to differences in QC-philosophy and differences in the available resources. CONCLUSIONS: Based on the results of the questionnaires and the comparison with the international recommendations, a set of minimum requirements for QC of brachytherapy has been formulated. These guidelines will be implemented in the radiotherapy institutions in The Netherlands and Belgium.

Belgium↗

PubMedDate not supplied

[Design of a program of quality control of nursing in an intensive care unit].

Although in the last few years care quality programs have started to be used in services, these are still few in nursing equipment. Our aim is to show the process we have followed to design a nursing care quality program in ICU. We developed the stages of process, where a list of general activities performed in the service was created to establish a priority later, as it was necessary, due to the high number of aspects or activities to monitor, to choose those we would use to start the quality control program. The ultimate order was settled with the following activities: 1. Surveillance of the infection. 2. Accidental withdrawal of tubes and catheters. 3. Pressure ulcers.

Humans↗

PubMed2006

Tunnel placement in anterior cruciate ligament (ACL) reconstruction: quality control in a teaching hospital.

Correct placement of the femoral and tibial bone tunnels is decisive for a successful anterior cruciate ligament (ACL) reconstruction. Our method of tunnel placement was evaluated as part of quality control at a teaching hospital. The emphasis was placed mainly on investigating the influence of surgical experience on tunnel placement, and the effect of tunnel position on the clinical outcome. Seventeen surgeons with different levels of experience (between 0 and >150 ACL reconstructions) performed endoscopic ACL repair in uniform technique from August 2000 to August 2003 on 50 patients (18 women, 32 men, age range 18-43 years). The patients were available to clinical and radiological follow-up after an average of 19 months. The clinical outcome was classified according to the International Knee Documentation Committee (IKDC) standard evaluation form. The femoral tunnel was evaluated according to the quadrant method of Bernard and Hertel; the position of the tibial bone tunnel was assessed according to the criteria of Stäubli and Rauschnig. The IKDC score revealed 47 (94%) patients with a normal (A) or nearly normal (B) knee joint at follow-up. According to the quadrant method, the femoral canal was situated on average at 29% in the saggital plane. The tibial tunnel was situated on average at 43% of the a.p. diameter of the tibial condyle. Statistical analysis of our data showed no significant correlation between tunnel placement and surgical expertise. However, a highly significant correlation was found (alpha<0.01) between the femoral position of the tunnel in the sagittal plane and the IKDC score. The more anterior the femoral canal, the poorer the IKDC score. The method of tunnel placement in ACL reconstruction being investigated here only showed slight dependence on surgical experience, whereby good short-term clinical outcomes were achieved. Therefore, the method is suitable for application at a teaching hospital. A far too anterior femoral tunnel placement will probably lead to a decline in the clinical result.

Adult↗

PubMed1985

A set of X-ray test objects for quality control in television fluoroscopy.

The history of performance testing in Leeds of television fluoroscopic systems is briefly outlined. Using the visual, physical and technological requirements as a basis, a set of nine test objects for quality control in television fluoroscopy is described. The factors measured by the test objects are listed in the introduction; the test objects and their function are fully described in the remainder of the paper. The test objects, in conjunction with a television oscilloscope, give both subjective and objective information about the X-ray system. Three of the test objects enable the physicist or engineer to adjust certain aspects of the performance of the X-ray system. The set of nine test objects is available commercially.

Fluoroscopy↗

PubMed1989

[Sterilization and quality control].

The dental profession has always considered the sterilization of surgical instruments as an important element in the prevention of infection. During the last decade the concern with blood and to a lesser degree with saliva in the transmission of infection, due primarily to the hepatitis and HIV viruses, has resulted in many corporate organizations releasing recommendations to reinforce the use of sterilization techniques and disinfection techniques when sterilization is not applicable or justifiable. As a result of the fact that the two terms are often intermingled, the authors review the fact that each one pursues different objectives and put the emphasis on sterilization by briefly reviewing the principal advantages and disadvantages of each method of sterilization presently available for use in dental offices. Subsequently, they stress the importance of introducing quality control in any infection prevention program, in order to assure that the sterilization process is not at the mercy of human error or mechanical failure. The pharmaceutical industry, food chains and hospital centres have for more than 40 years realized the importance of using chemical indicators and especially biological testing. Only biological testing can put one's mind at ease, for the professional in a dental office and the patient receiving care, that the instruments or objects that one comes in contact with are truly sterile. The dental profession did not wait for the discovery of the hepatitis B and HIV viruses to become preoccupied with the spread of disease and have sterilized their surgical instruments for many years.(ABSTRACT TRUNCATED AT 250 WORDS)

Communicable Disease Control↗

PubMedDate not supplied

Cathode ray tube quality control and acceptance testing program: initial results for clinical PACS displays.

The use of picture archiving and communication systems (PACS) and primary soft-copy interpretation in radiology is growing rapidly. The authors present a cathode ray tube (CRT) acceptance test and quality control (QC) program developed over a 5-year period on the basis of experience with multiple PACS and CRT vendors. The CRT QC procedures address monitor cleanliness and setup, qualitative image quality, and quantitative luminance and color measurements. Required materials include a photometer with luminance and color probes and 100%-video, flat-field window and test images from the Society of Motion Picture Test Engineers (SMPTE). Luminance was found to change over time for all gray-scale CRTs examined, which necessitated quarterly recalibration. The phosphor color of these monitors was also found to change, but changes were consistent and slow enough to warrant only annual measurements. Color measurements were found to be especially useful at initial setup and for CRT replacement. Use of this program allowed standardization of absolute luminance of individual CRTs, matching of phosphor color for multimonitor workstations, and systematic tracking of image artifacts. Implementation of a QC program is strongly recommended owing to the dynamic nature of CRT displays.

Color↗

PubMed1988

External quality control in the determination of neonatal bilirubin. An approach to the improvement of results.

The reliability of bilirubin analyses is especially important in cases of neonatal hyperbilirubinaemia. However, when the means of the results of external quality control surveys and the method-dependent stated values for control sera were compared with reference method values, differences of up to 10% were found. Further inaccuracy arose from interlaboratory imprecision, which showed coefficients of variation of at least 7%, and from greater or lesser interference from contamination of samples with haemoglobin. The present work investigates whether the current situation can be improved by available means.

Bilirubin↗

PubMed1977

Preparation and use of a quality control hemolysate for microchromatographic determinations of hemoglobin A2.

Compared with other methods for determining hemoglobin A2 (Hb A2) levels, the new microchromatography procedures are fast, easy laboratory technics useful for quantitating Hb A2 that can be readily monitored for quality control of results. A reliable method for preparing a stable hemolysate control for monitoring the accuracy and precision of Hb A2 microchromatographic procedures is described. The recombination of purified hemoglobin fractions in known concentrations and the addition of potassium cyanide and carbon monoxide produce a control solution that gives stable hemoglobin A2 values for at least 40 weeks. Variability among six reference laboratories was small.

Chromatography↗

PubMed1993

Quality control of bacterial enumeration.

Standard bacterial suspensions can be used to assess test method performance, via control charts, and inhibition of recovery when analyzing water samples. Variability in standard suspensions prepared from different strains and species and the use of frozen environmental samples for quality control for spore and bacteriophage analyses are also discussed.

Bacteria↗

PubMed2005

Implementation of the European protocol for quality control of the technical aspects of mammography screening in Bulgaria.

The results from the national pilot project on implementation of the European protocol for the quality control (QC) of the technical aspects of mammography screening as well as the European protocol for dosimetry in mammography in Bulgaria are presented. A QC programme for mammography equipment and a standardised measurement protocol were created. The full QC programme was tested on four mammography units of different types and ages. A national survey was performed for entrance surface air kerma (ESAK) on 20 units using a 45 mm PMMA standard phantom. Average glandular dose (AGD) was calculated using the conversion coefficients from the European dosimetry protocol. The survey demonstrated considerable differences in the technical condition of the mammography units that resulted in varying image quality. The measured values of ESAK showed significant variations. Doses for approximately 45% of the units were found to be below the European reference level. The values for AGD ranged from 0.35 to 3.47 mGy. The main problems found were film processing, optical density (OD) control settings and AEC adjustment. The results showed the importance of film OD measurements parallel to dose measurements. The X-ray mammography in the country needs optimisation. Comprehensive quality assurance programme should be adopted in all departments covering permanent QC of the equipment, image quality and breast dose.

Breast↗

PubMed2005

PROQUR: a tool for quality control, epidemiological surveillance, patient follow-up and clinical research activities related to prostate cancer.

Prostate cancer is a leading cancer in Western Europe and epidemiological surveillance is essential to better understand the disease and its treatment. A database for quality control starting with the diagnostic procedure transrectal ultrasound guided core biopsy of the prostate was designed with the aim of monitoring side-events to the procedure, direct printing of reports and forms related to the diagnostic procedure, the National Cancer Registry and the National Prostate Cancer Quality Registry. The programme is flexible, and new folders related to specific research activities can be attached. The programme is easy to handle and aimed at facilitating the daily work of the urologist, epidemiological surveillance and disease progression. We suggest the programme should become a common tool and platform for a standardised approach in diagnostic, therapeutic, administrative reporting to the National Cancer Registry and National Prostate Cancer Quality Registry, and research on prostate diseases in the urologic community in Sweden and eventually abroad.

Adult↗

PubMed1988

Replicate tests for the detection and correction of errors in anti-human globulin (AHG) tests: optimum conditions and quality control.

Replicate blind AHG tests with weak IgG anti-D sensitised red cells revealed that 32% of workers caused 5 per cent or more false negative errors by using excessive agitation in reading techniques. The common quality control procedure of adding strongly sensitised cells to all negative AHG tests cannot reveal this type of error. Furthermore, strongly sensitised control cells may create an illusion of safety because AHG giving a false negative test with weak antibody in a serum sample may still show a reassuringly strong positive in the control test. "In-house" assessment of all staff and automatic cell-washers by blind replicate tests is recommended as an effective way of improving AHG test performance, thus reducing many of the errors involving false negative AHG tests seen year after year in External Proficiency Trials.

Antibodies↗

PubMed2006

Refractometry for quality control of anesthetic drug mixtures.

Injectable anesthetic drugs used in rodents are often mixed and further diluted to increase the convenience and accuracy of dosing. We evaluated clinical refractometry as a simple and rapid method of quality control and mixing error detection of rodent anesthetic or analgesic mixtures. Dilutions of ketamine, xylazine, acepromazine, and buprenorphine were prepared with reagent-grade water to produce at least 4 concentration levels. The refraction of each concentration then was measured with a clinical refractometer and plotted against the percentage of stock concentration. The resulting graphs were linear and could be used to determine the concentration of single-drug dilutions or to predict the refraction of drug mixtures. We conclude that refractometry can be used to assess the concentration of dilutions of single drugs and can verify the mixing accuracy of drug combinations when the components of the mixture are known and fall within the detection range of the instrument.

Acepromazine↗

PubMed1990

Predicting effects of quality-control practices on the cost-effective operation of a stable, multitest analytical system.

The cost-effective operation of an analytical system depends on quality-control (QC) practices such as the QC procedure itself (control rules, number of control measurements); the batch size or the run length; and the use of bracketed, nonbracketed, or pre-control modes of operation. Predictive value models that predict the defect rate and test yield of each test, as well as of the system as a whole, have been used to study these practices and to develop strategies for improving the quality and productivity of a multitest analyzer. Quality was optimized for most tests by achieving high error detection and low false rejection by the QC procedures. For a few tests where ideal QC performance could not be achieved, predictive models indicate that high quality is achieved, predictive models indicate that high quality is achieved as long as the observed stabilities (low frequencies of errors) of the measurement procedures are maintained. In our laboratories, productivity gains of 2.9% ($17,400/year) were achieved by changing QC procedures. Predictive models indicate that further gains are possible by increasing batch size and changing from bracketed to nonbracketed control operation. In general, the common practice of bracketed control on stable analytical systems may need to be re-examined owing to its effect on the cost of operation.

Chemistry, Clinical↗