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PubMed1998

[Guidelines for the evaluation of internal quality control of smears for screening of uterine cancer in France in the structures of Pathologic Anatomy and Cytology. French Association for Quality Assurance in Pathologic Anatomy and Cytology (AFAQAP)--Commission for cervical smears].

A national organized mass-screening effective programme is the only way to reduce the risk of cervical cancer, if properly organized and correlated with a system of Quality Assurance. Since 1900, an Association for Quality Assurance was created by the French pathologists, named "AFAQAP". These pathologists thus demonstrated their interest in this kind of action that should be effective if women and clinicians are also implied. The pathologists have concluded the first part of their programme with these French guidelines for internal quality control of pap smears.

Female↗

PubMed1977

Protective effect of glycerol against the increase in alkaline phosphatase activity of lyophilized quality-control serum.

We studied the effectiveness of glycerol or ethylene glycol in preventing the increase in alkaline phosphatase activity of lyophilized or refrigerated quality-control serum after reconstitution or repeated freezing and thawing. Control serum reconstituted completely from the lyophilized state with subsequent storage at -20 degrees C showed a considerable decrease in alkaline phosphatase activity immediately after thawing, and a gradual increase in activity on allowing it to stand at room temperature. Adding glycerol or ethylene glycol to the reconstituted serum obviated these changes in activity, glycerol being more effective than ethylene glycol. Reconstituted serum with added glycerol maintained maximum activity before refrigeration during either storage for 30 days or on repeated freezing and thawing. Practical applications of this glycerol-supplemented control serum are discussed.

Alkaline Phosphatase↗

PubMed2000

ROP-1, an RNA quality-control pathway component, affects Caenorhabditis elegans dauer formation.

Caenorhabditis elegans dauer formation is an alternative larval developmental pathway that the worm can take when environmental conditions become detrimental. Animals can survive several months in this stress-resistant stage and can resume normal development when growth conditions improve. Although the worms integrate a variety of sensory information to commit to dauer formation, it is currently unknown whether they also monitor internal cellular damage. The Ro ribonucleoprotein complex, which was initially described as a human autoantigen, is composed of one major 60-kDa protein, Ro60, that binds to one of four small RNA molecules, designated Y RNAs. Ro60 has been shown to bind mutant 5S rRNA molecules in Xenopus oocytes, suggesting a role for Ro60 in 5S rRNA biogenesis. Analysis of ribosomes from a C. elegans rop-1(-) strain, which is null for the expression of Ro60, demonstrated that they contain a high percentage of mutant 5S rRNA molecules, thereby strengthening the notion of a link between the rop-1 gene product and 5S rRNA quality control. The Ro particle was recently shown to be involved in the resistance of Deinococcus radiodurans to UV irradiation, suggesting a role for the Ro complex in stress resistance. We have studied the role of rop-1 in dauer formation. We present genetic and biochemical evidence that rop-1 interacts with dauer-formation genes and is involved in the regulation of the worms' entry into the dauer stage. Furthermore, we find that the rop-1 gene product undergoes a proteolytic processing step that is regulated by the dauer formation pathway via an aspartic proteinase. These results suggest that the Ro particle may function in an RNA quality-control checkpoint for dauer formation.

Animals↗

PubMed1995

Image quality control for digital mammographic systems: initial experience and outlook.

This report presents (1) a broad topical review and a tutorial of the possibilities for image quality control (IQC) with digital systems, and (2) results and initial experience for IQC with two commercial digital imaging systems, but with limited discussion on any particular method. Digital imaging systems used for mammographically guided digital stereotactic breast biopsy were evaluated extensively at the University of Arizona. Measurements were made of linearity, sensitivity, signal-to-noise ratio, and square-wave modulation. Images of phantoms such as the American College of Radiology Accreditation Phantom and the contrast detail mammography Phantom were evaluated as well as images of the x-ray source's focal spot. The evaluation also included the cathode ray tubes for the imaging systems. The data collected show that digital imaging systems have an important advantage over film-screen systems because they provide a digital signal as output that can be used for quantitative analysis. As a result, IQC can become a much more quantitative discipline than presently practiced, providing more information on the imaging systems under evaluation, and providing better control over their properties during actual operation.

Computer Terminals↗

PubMed2005

Quality control of involved-field radiotherapy in patients with advanced Hodgkin's lymphoma (EORTC 20884).

PURPOSE: To evaluate the impact of the quality of involved-field radiotherapy (IFRT) on clinical outcome in patients with advanced Hodgkin's lymphoma (HL) in complete remission (CR) after six to eight cycles of mechlorethamine, vincristine, procarbazine, prednisone-doxorubicin, bleomycin, and vinblastine (MOPP-ABV) chemotherapy. METHODS AND MATERIALS: A retrospective review of clinical and radiologic data, radiation charts, simulator films, and megavoltage (MV) photographs was performed. IFRT consisted of 24 Gy to all initially involved nodal areas and 16-24 Gy to all initially involved extranodal sites. Major violations were defined as no or only partial irradiation of an originally involved area, or a total dose <90% of the prescribed dose. RESULTS: Of the 739 patients who were enrolled in the trial between 1989 and 2000, 57% achieved a CR; 152 of 172 patients randomized to IFRT actually received radiotherapy; and in 135 patients, quality control was performed. The overall major violation rate was 47%, predominantly concerning target volumes. The total dose was correct in 81% of the patients. After a median follow-up of 6.5 years, there was no difference in cumulative failure rate between patients with or without major violations. There was no relationship between incidence or site of relapse and major protocol violations. CONCLUSION: In advanced-stage HL patients in complete remission after six to eight cycles of MOPP-ABV, the outcome was not influenced by violation of the radiotherapy protocol.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2003

Antimicrobial susceptibility testing of aquatic bacteria: quality control disk diffusion ranges for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28 degrees C.

Quality control (QC) ranges for disk diffusion susceptibility testing of aquatic bacterial isolates were proposed as a result of a multilaboratory study conducted according to procedures established by the National Committee for Clinical Laboratory Standards (NCCLS). Ranges were proposed for Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658 at 22 and 28 degrees C for nine different antimicrobial agents (ampicillin, enrofloxacin, erythromycin, florfenicol, gentamicin, oxolinic acid, oxytetracycline, ormetoprim-sulfadimethoxine, and trimethoprim-sulfamethoxazole). All tests were conducted on standard Mueller-Hinton agar. With >/=95% of all data points fitting within the proposed QC ranges, the results from this study comply with NCCLS guidelines and have been accepted by the NCCLS Subcommittee for Veterinary Antimicrobial Susceptibility Testing. These QC guidelines will permit greater accuracy in interpreting results and, for the first time, the ability to reliably compare susceptibility test data between aquatic animal disease diagnostic laboratories.

Aeromonas↗

PubMedDate not supplied

Cefmetazole and trospectomycin in vitro susceptibility testing interpretive criteria and quality control guidelines for Neisseria gonorrheae.

Cefmetazole and trospectomycin were tested in a multilaboratory trial to establish Neisseria gonorrhoeae susceptibility testing criteria and quality control (QC) guidelines. Cefmetazole was active against the penicillinase-producing isolates and has an MIC90 of 16 micrograms/ml, the breakpoint MIC previously used for nonfastidious species. However, a single-dose gonorrhea regimen (1 g i.m.) would require a lower less than or equal to 2 micrograms/ml breakpoint with a correlate zone (greater than or equal to 33 mm) consistent with similarly used cephamycins (cefoxitin and cefotetan). An intermediate category was proposed for MICs greater than 2-4 micrograms/m (28-32 mm) pending more clinical experience with higher and/or prolonged cefmetazole dosing regimens. Trospectomycin was active (MIC90, 8 micrograms/ml) against all spectinomycin-susceptible gonococci. A susceptible breakpoint MIC of less than or equal to 16 micrograms trospectomycin per milliliter was proposed with a correlate zone diameter of greater than or equal to 17 mm. An intermediate category was also suggested for trospectomycin at 32 micrograms/ml (14-16 mm). QC guidelines were established for 30-micrograms cefmetazole and 30-micrograms trospectomycin disk diffusion tests and the GC agar base MICs using a multilaboratory study design consistent with National Committee for Clinical Laboratory Standards (NCCLS) M23-T guidelines. Both drugs were stable in GC agar plates for 21 days stored at 2 degrees-5 degrees C.

Cefmetazole↗

PubMed1993

[Review of quality control program for clinical microbiology developed by the Tokyo Metropolitan Government].

UNLABELLED: There are limitations or disadvantages in previous nation wide external quality control (QC) programs. Therefore, the Tokyo Metropolitan Government and the Tokyo Medical Association (TMA) initiated the first regional annual external QC program in 1982. The QC results in chemistry, hematology and immunology have shown rapid improvement. By contrast, some serious problems in microbiology have been revealed. METHODS AND RESULTS: The Tokyo Metropolitan external QC programs consist of so-called "open" and "blind" surveys. Simulated specimens were prepared for open and blind surveys and all laboratories were asked to examine the specimens using routine procedures. All participants were required to report not only their test results such as codes for computer analysis, but also to describe the process. Written answers included the following subjects, procedures, culture characteristics and others: number and type of selective media, incubation conditions, colonial morphology, microscopic and biochemical characteristics of the microorganisms, etc. The survey reports on the identification of some kinds of pathologic organism were inaccurate. Discrepancies between the number of media used for routine procedures and the number used in open survey were detected. CONCLUSIONS: Previous nationwide external QC programs using frozen-dried organisms have been valuable in promoting general improvement in clinical microbiology in Japan, but they have revealed only gross errors. Our 10-year experience has convinced us that additional important information is obtained when using simulated specimens for open and blind surveys. The turnaround time and other aspects of the reporting of results should be monitored. Due to possible legal ramifications of QC surveys, laboratories are now more afraid of making errors than before. The continuing education of laboratory personnel is essential.

Humans↗

PubMed1983

Preparation and characterization of a human serum matrix suitable for quality control or reference materials.

We describe the preparation of a human serum based matrix suitable for inclusion in long-term control materials. The procedure entails the removal of cells, fibrin and lipoproteins from blood to produce a clear, stable material which has been stored frozen at -70 degrees C for up to 14 mth without any apparent deterioration. When incorporated into a quality control material, storage at 4 degrees and -20 degrees C may cause a change in several unstable constituents, but the material remains optically clear. A noticeable reduction in lipoprotein as a result of the preparative procedure is probably responsible for the continued clarity of the matrix. The nature of the matrix has been examined by polyacrylamide gel electrophoresis and does not reveal any unusual protein bands, whereas commercially available materials when similarly examined often reveal protein bands not present in normal serum. The matrix has been used to prepare control material for the Chemical Pathology Quality Assurance Programme Group of the Royal College of Pathologists of Australasia/Australian Association of Clinical Biochemists.

Blood Chemical Analysis↗

PubMedDate not supplied

Pero Vaz de Caminha: an-interchange program for quality control between Brazil and Portugal.

OBJECTIVE: To start an interexchange program for quality control in cervical cytology and discuss conceptual criteria for diagnosis. STUDY DESIGN: Slides were selected in the archives of the 2 institutes and included cases with unsatisfactory, negative and positive results. Sets of slides were changed between the partners every 3 months. At the end of each year a senior cytopathologist was invited to discuss the major discrepancies found in the study. RESULTS: A total of 1,041 cases were analyzed. Full concordance was obtained in 74.4% (774) of cases and discrepancies in 25.6% (267 cases). Full agreement was achieved in 276 (39%) of 707 cases categorized as negative. In 421 negative cases from laboratory A, this concordance represents 65.5% and 96.5% for laboratory B, which submitted 286 negative cases. The main discordance was the high number of atypical squamous cells of undetermined significance cases: 3.1% for A and 128 (33.2%) for B. Samples with discrepancies related to the quality of the material was another controversial issue: of 16 cases from laboratory A, 6 (37.5%) unsatisfactory cases were the same and 10 (62.5%) different. Laboratory B presented 20 unsatisfactory cases, and 14 (70.0%) had other diagnoses. Low grade squamous intraepithelial lesion and high grade squamous intraepithelial lesion concordance ranged from 75% to 80%, and invasive carcinoma has 4 discordances (28.5%), 3 previously screened as high grade squamous intraepithelial lesion and 1 as atypical squamous cells of undetermined significance. The kappa value obtained was 0.65, indicating substantial agreement. CONCLUSION: Our results indicated that atypical squamous cells of undetermined significance diagnoses are the crucial point of controversies and concern the quality of routine diagnosis in cytopathology.

Attitude of Health Personnel↗

PubMed1999

A quality control program for acute pain management in out-of-hospital critical care medicine.

STUDY OBJECTIVE: This study was conducted to evaluate a quality control program for improving pain treatment in the out-of-hospital setting. METHODS: Pain was evaluated for all patients at the beginning (T(0)) and the end (T(end)) of out-of-hospital management. During the first part of the study (part 1, n=108), the administration and choice of analgesics was left to the physician's discretion. Pain protocols were then modified to encourage the use of opioids. The effectiveness of this new pain management was analyzed (part 2, n=105) using pain scales and quality of relief. RESULTS: Seventy percent of patients who expressed meaningful pain did not request analgesia, and 36% did not receive any analgesia in part 1 in contrast to 7% in part 2 of the study. The verbal rating scale and visual analog scale scores were substantially improved at T(end) versus T(0) in both periods, but the improvement was greater in part 2 (mean visual analog scale score at T(end) was 29.3+/-23 mm [+/-SD]) than in part 1 (38.6+/-25 mm). The percentage of patients who expressed satisfactory relief increased in part 2 (67% versus 49% in part 1). The mean dose of intravenous morphine was 7.2+/-6 mg. Adverse effects were rare and minor. CONCLUSION: This program focusing on pain treatment plus implementation of pain protocols (with intravenous morphine) improved pain management in the field.

Adult↗

PubMedDate not supplied

Quality control for biomarker determination in oncology: the experience of the Italian Network for Quality Assessment of Tumor Biomarkers (INQAT).

Biomarker analysis and evaluation in oncology is the product of a number of processes (including managerial, technical and interpretation steps) which need to be monitored and controlled to prevent and correct errors and guarantee a satisfactory level of quality. Several biomarkers have recently moved to clinical validation studies and successively to clinical practice without any definition of standard procedures and/or quality control (QC) schemes necessary to guarantee the reproducibility of the laboratory information. In Italy several national scientific societies and single researchers have activated -- often on a pilot level -- specific external quality assessment protocols, thereby potentially jeopardizing the clinical reality even further. In view of the seriousness of the problem, in 1998 the Italian Ministry of Health sponsored a National Survey Project to coordinate and standardize the procedures and to develop QC programs for the analysis of cancer biomarkers of potential clinical relevance. Twelve QC programs focused on biomarkers and concerning morphological, immunohistochemical, biochemical, molecular, and immunoenzymatic assays were coordinated and implemented. Specifically, external QC programs for the analytical phase of immunohistochemical p53, Bcl-2, c-erb-2/neu/HER2, and microvessel density determination, of morphological evaluation of tumor differentiation grade, and of molecular p53 analysis were activated for the first time within the project. Several hundreds of Italian laboratories took part in these QC programs, the results of which are available on the web site of the Network (www.cqlaboncologico.it). Financial support from the Italian Government and the National Research Council (CNR) will guarantee the pursuit of activities that will be extended to new biomarkers, to preanalytical phases of the assays, and to revision of the criteria of clinical usefulness for evaluating the cost/benefit ratio.

Autoradiography↗

PubMed1987

A set of X-ray test objects for image quality control in digital subtraction fluorography. II: Application and interpretation of results.

In the previous article we introduced a set of test objects for quality control of digital subtraction fluorography (DSF) systems. These test objects have been evaluated using several commercial DSF systems in their clinical environment. In this second article we present test images and results obtained during these trails and explain how the test objects can be used to analyse the imaging performance of DSF systems.

Fluoroscopy↗

PubMed1985

Interpretive standards and quality control guidelines for cefpiramide disk susceptibility tests.

Disk susceptibility tests with 30- and 75-micrograms cefpiramide disks were evaluated with 614 bacterial isolates. Quality control parameters were also evaluated, and control limits for disk tests are recommended. Tests with 75-micrograms disks are recommended, with zone size standards of greater than or equal to 19 mm for susceptible (MIC, less than or equal to 32 micrograms/ml) and less than or equal to 15 mm for resistant (MIC, greater than or equal to 128 micrograms/ml).

Cephalosporins↗

PubMed1980

Outlying values in the National Quality Control Scheme.

A modified statistical method for the detection of outlying values has been applied to five fortnightly sets of data from the National Quality Control Scheme. The overall outlier rate was 2.4%, not varying greatly between analytes. Many of the outliers appear to be due to sample identification errors.

Chemistry, Clinical↗

PubMed2002

Nondestructive quality control for microarray production.

The use of microarrays to monitor gene expression has become a standard research tool at both academic and industrial research institutions. Quality control of common printing defects during DNA deposition onto glass substrates is critical to maintaining data integrity and preventing the needless consumption of precious RNA, labeling reagents, and time. Here we demonstrate a nondestructive method for monitoring the quality of every spot on every chip of a microarray production run. We have identified many common manufacturing defects, while not perturbing the attachment of our oligonucleotide target to the substrate or altering further hybridization. This protocol is simple, fast, and inexpensive.

Carbocyanines↗

PubMed1984

Quality control of susceptibility tests with 5-micrograms trimethoprim disks.

In 1981 and again in 1984, we performed multi-laboratory studies to develop quality control limits for susceptibility tests with 5-micrograms trimethoprim disks. Zone size limits of 21 to 28 mm are recommended for tests with Escherichia coli ATCC 25922, and limits of 19 to 26 mm are recommended for tests with Staphylococcus aureus ATCC 25923. For screening Mueller-Hinton agar, tests with Streptococcus faecalis ATCC 33186 or ATCC 29212 are recommended: zones should be fairly clear and greater than or equal to 22 mm (trimethoprim disks) or greater than or equal to 24 mm (trimethoprim-sulfamethoxazole disks).

Drug Combinations↗

PubMed2000

[Radiographic image magnification as quality control of microcalcification imaging within the scope of histopathological control of breast biopsy tissue].

PURPOSE: Evaluation of specimen radiography as a quality control for the detection of microcalcifications by the pathologist during histopathological examination of breast biopsies. MATERIALS AND METHODS: 29 breast biopsy specimen with microcalcifications were radiographed using the magnification (x4) mammography System DIMA Plus MI I before and after the histopathological examination. Tissue with detected microcalcifications after the histopathological examination was reexamined histologically. RESULTS: In 55% (16/29) of all specimen we could identify missed microcalcifications. In 5 specimens the microcalcifications were missed completely. The radiologically detected areas of residual microcalcifications were reexamined histologically and in one case invasive parts of a carcinoma were detected, which primarily had been diagnosed as an in-situ carcinoma. In 6 cases the radiographs of the intraoperative specimen radiography were sent to the pathologist together with the biopsy. In these cases the rate of complete detection of the microcalcifications increased from 39% to 66%. CONCLUSION: Specimen radiography should be performed not only intraoperatively but also as part of the histopathological examination.

Biopsy, Needle↗