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PubMed1999

Proficiency test for screening mammography: results for 117 volunteer Italian radiologists.

OBJECTIVE: To analyse the performance of a large sample of Italian radiologists undergoing a proficiency test for screening mammography. DESIGN: Evaluation of performance indicators according to reference standards determined by a panel of experts (sensitivity (reference standard > or = 80%), recall rate (reference standard < or = 15%)). SETTING: 117 Italian radiologists of varying experience (years of practice 0.5-18, average 5.9; mammograms read 500-51,000, average 13,000), all currently reporting clinical mammography and planning to take part in screening in the near future. RESULTS: Eighty four of 117 (72%) radiologists reached the standard for sensitivity, 88 (75%) reached the standard for recall rate, and only 59 (50%) reached both standards and passed the proficiency test. The probability of passing the test was significantly correlated with mammographic practice (p = 0.015), mammograms read (p = 0.024), and mammograms read/year (p = 0.043). DISCUSSION: The performance of a large sample of Italian radiologists currently reporting clinical mammography was disappointing, indicating the need for proper training of at least 50% of the tested subjects. When implementing organised screening the health authority should set up a proper process for training and accrediting radiologists, and a proficiency test should be part of such a process.

Chi-Square Distribution↗
PubMedDate not supplied

How to find Chinese research participants: use of a phonologically based surname search method.

The frequent use of non-representative, time-consuming and low hit rate sampling methods in the study of minority cultures is of concern. Given the increasing cultural diversity of the Canadian population and the growing Chinese population, a sampling method using phonological rules to distinguish Chinese surnames from non-Chinese ones was developed. Chinese surnames, transcribed according to their pronunciations, follow specific phonological rules. A flowchart was developed using the inclusion and exclusion criteria derived from these rules. Methods to validate Chinese surnames (identified from telephone directory) were external reference source, expert panel, and telephone interview. A total of 266 possible Chinese surnames were selected using the flowchart. External reference source validated 153 surnames, expert panel 53, and telephone interview 23. An overall hit rate of 86.1% (229/266) was achieved, reflecting the validity of the phonological criteria in identifying individuals with a Chinese surname from the general population.

China↗
PubMed2001

Trends in antifungal susceptibility among Swedish Candida species bloodstream isolates from 1994 to 1998: comparison of the E-test and the Sensititre YeastOne Colorimetric Antifungal Panel with the NCCLS M27-A reference method.

A comparative evaluation of the NCCLS macrodilution method, the E-test, and the Sensititre YeastOne Colorimetric Antifungal Panel for the susceptibility testing of fluconazole, itraconazole, amphotericin B, and flucytosine was conducted with 233 blood isolates of Candida species collected between 1994 and 1998 in Sweden. Antifungal susceptibility profiles of Candida albicans and non-C. albicans Candida species remained essentially unchanged within the 5-year study period. The overall agreement rates for the E-test and the NCCLS MICs and for the YeastOne and the NCCLS MICs were > or =86 and > or =87%, respectively, within +/-1 dilution for fluconazole, amphotericin B, and flucytosine, and > or =66 and > or =57%, respectively, for itraconazole. The E-test and the YeastOne panels are equivalent, and both are convenient methods for routine use.

Antifungal Agents↗
PubMed1996

Clinical evaluation of a dried commercially-prepared microdilution panel for antifungal susceptibility testing.

A commercially-prepared dried broth microdilution panel (Sensititre) was compared with a reference microdilution method for antifungal susceptibility testing of two reference yeast strains and 98 clinical isolates of Candida spp. The antifungal agents tested include 5-fluorocytosine (5FC), fluconazole, itraconazole, and D0870. Microdilution testing was performed according to National Committee for Clinical Laboratory Standards (NCCLS) recommendations. Minimum inhibitory concentration (MIC) endpoints were read visually after 48 hours of incubation and were assessed independently for each microdilution panel. The MICs for the reference strains were within published control limits for both reference and Sensititre microdilution panels. Discrepancies among MIC endpoints of no more than two dilutions (two wells) were used to calculate the percent agreement. An acceptable level of agreement between Sensititre and reference panels was observed for all antifungal agents when tested against the 98 clinical isolates. Agreement ranged from 83% for itraconazole to 93% for 5FC. The Sensititre dried microdilution panel appears to be a viable alternative to inhouse prepared microdilution panels and to the NCCLS microdilution reference method.

Antifungal Agents↗
PubMed1992

Working and reference memory in rats in the three-panel runway task following dorsal hippocampal lesions.

Using a three-panel runway task, the influence of dorsal hippocampal lesions on working and reference memory in rats was investigated. Despite 20 postoperative training sessions, rats with hippocampal lesions were unable to perform the working memory task. In the acquisition process of the reference memory task, however, there was no significant difference between hippocampal- and sham-lesioned rats. On the other hand, rats trained preoperatively with a working memory procedure, and then subjected to hippocampal lesions, showed more errors (pushes made on the two incorrect panels of the three panel-gates located at four choice points) than did sham-lesioned rats. The increase in working errors induced by hippocampal lesions was not reduced during 10 subsequent re-training sessions. Hippocampal lesions had no effect on retention of the reference memory performance. The increase in working errors in hippocampal-lesioned rats was significantly reduced by treatment with the cholinesterase inhibitor physostigmine at 0.1 mg/kg and the cholinergic activating drug minaprine at 10 mg/kg. These findings suggest that lesions of the dorsal hippocampus selectively impair the ability to carry out the working memory task whether rats are trained preoperatively or postoperatively, and that the working memory loss in hippocampal-lesioned rats is mediated by lowering of the cholinergic function.

Animals↗
PubMed1998

A comprehensive panel of near-full-length clones and reference sequences for non-subtype B isolates of human immunodeficiency virus type 1.

Non-subtype B viruses cause the vast majority of new human immunodeficiency virus type 1 (HIV-1) infections worldwide and are thus the major focus of international vaccine efforts. Although their geographic dissemination is carefully monitored, their immunogenic and biological properties remain largely unknown, in part because well-characterized virological reference reagents are lacking. In particular, full-length clones and sequences are rare, since subtype classification is frequently based on small PCR-derived viral fragments. There are only five proviral clones available for viruses other than subtype B, and these represent only 3 of the 10 proposed (group M) sequence subtypes. This lack of reference sequences also confounds the identification and analysis of mosaic (recombinant) genomes, which appear to be arising with increasing frequency in areas where multiple sequence subtypes cocirculate. To generate a more representative panel of non-subtype B reference reagents, we have cloned (by long PCR or lambda phage techniques) and sequenced 10 near-full-length HIV-1 genomes (lacking less than 80 bp of long terminal repeat sequences) from primary isolates collected at major epicenters of the global AIDS pandemic. Detailed phylogenetic analyses identified six that represented nonrecombinant members of HIV-1 subtypes A (92UG037.1), C (92BR025. 8), D (84ZR085.1 and 94UG114.1), F (93BR020.1), and H (90CF056.1), the last two comprising the first full-length examples of these subtypes. Four others were found to be complex mosaics of subtypes A and C (92RW009.6), A and G (92NG083.2 and 92NG003.1), and B and F (93BR029.4), again emphasizing the impact of intersubtype recombination on global HIV-1 diversification. Although a number of clones had frameshift mutations or translational stop codons in major open reading frames, all the genomes contained a complete set of genes and three had intact genomic organizations without inactivating mutations. Reconstruction of one of these (94UG114.1) yielded replication-competent virus that grew to high titers in normal donor peripheral blood mononuclear cell cultures. This panel of non-subtype B reference genomes should prove valuable for structure-function studies of genetically diverse viral gene products, the generation of subtype-specific immunological reagents, and the production of DNA- and protein-based subunit vaccines directed against a broader spectrum of viruses.

Adolescent↗
PubMed2005

A multi-centre pilot proficiency programme to assess the quality of molecular detection of respiratory viruses.

OBJECTIVES: To assess the quality of molecular detection of respiratory viruses in clinical diagnostic laboratories. STUDY DESIGN: Respiratory virus proficiency panels were produced from diluted stocks of respiratory viruses provided and tested by four reference laboratories. The panels consisted of strong positive, positive, low positive and negative samples for influenza viruses A and B, respiratory syncytial virus, parainfluenza viruses 1 and 3, adenovirus serotypes 4 and 7, human rhinovirus serotypes 16, 72 and 90, human coronaviruses OC43 and 229E. The panels were sent to 17 participants; results and information on methodology was collected. RESULTS: All laboratories returned results, of which five submitted complete data sets. So, for analysis all results were combined. Samples were correctly identified by participants in 93.75%, 76.75% and 47.03% for the high positive, positive and low positive samples, respectively. One false positive was reported for all data sets (1.1%). The overall score for all assays using different methodologies was 78.8%. Laboratory performance was not dependant on methodology as all in-house methodologies could achieve optimal results, but dependant on careful optimisation and procedures specific to the laboratory. CONCLUSIONS: The first proficiency panel showed that in general all participants performed well. Although, it also highlights areas for improvement for all participants in order to generate robust results for use in clinical diagnostics.

Adenoviruses, Human↗
PubMed2004

Use of TP53 reference materials to validate mutations in clinical tissue specimens by single-strand conformational polymorphism analysis.

BACKGROUND: As genetic information moves from basic research laboratories in to the clinical testing environment, there is a critical need for reliable reference materials for the quality assurance of genetic tests. A panel of 12 plasmid clones containing wild-type or point mutations within exons 5-9 have been developed as reference materials for the detection of TP53 mutations. AIM: The goal of this study was to validate the reference materials in providing quality assurance for the detection of TP53 mutations in clinical specimens. METHODS: We studied 33 gynecological samples, 11 apparently normal samples and 22 malignant tumors of various origins. Mutations were identified using single-strand conformational polymorphism analysis with both slab gel and capillary electrophoresis. All DNA samples were amplified with fluorescently labeled PCR primers specific for exons 5-9 for mutation detection. RESULTS: Of the 33 patient samples tested, mutations and polymorphisms were found in six specimens in three of the five exons scanned; no mutations were found in exons 7 or 9. Both a mutation and polymorphism were found in non-malignant specimens from the control group. The mutations were confirmed by DNA sequence analysis of the regions scanned. CONCLUSIONS: Mutations and polymorphisms were detected in the clinical samples. All of the mutations were silent except for one non-conservative mutation in exon 5, codon 181. This study demonstrates the usefulness of the National Institute of Standards and Technology (NIST) TP53 reference panel in TP53 mutation detection in clinical tissue specimens.

Adolescent↗
PubMed2006

Small pulmonary nodules: effect of two computer-aided detection systems on radiologist performance.

PURPOSE: To prospectively compare the effects of two computer-aided detection (CAD) systems on the detection of small pulmonary nodules at multi-detector row computed tomography (CT) by using a consensus panel decision as the reference standard. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Multi-detector row CT scans were randomly chosen and prospectively evaluated in 25 patients. Two dedicated CAD systems-ImageChecker CT (R2 Technologies, Sunnyvale, Calif) and Nodule Enhanced Viewing (NEV) (Siemens Medical Solutions, Forchheim, Germany)-were used. Results were interpreted by three radiologists with 1, 3, and 6 years of experience. Images were evaluated without and with CAD software. The reference standard was assessed by a consensus panel consisting of all three radiologists and an adjudicator with 8 years of experience. RESULTS: A total of 116 pulmonary nodules (average diameter, 3.4 mm; average volume, 32.05 mm3) were found in all data sets during consensus interpretation, which included findings from the CAD software and all radiologists. Overall sensitivity was 73% with ImageChecker CT and 75% with NEV. Overall sensitivity without CAD was 68% for radiologist 1, 78% for radiologist 2, and 82% for radiologist 3. With ImageChecker CT, sensitivity increased to 79% for radiologist 1, 90% for radiologist 2, and 84% for radiologist 3. With NEV, sensitivity increased to 79% for radiologist 1, 90% for radiologist 2, and 86% for radiologist 3. The average number of false-positive findings was six (range, 0-14) with ImageChecker CT and eight (range, 0-22) with NEV. CONCLUSION: Radiologist performance in the interpretation of multi-detector row CT scans can be improved by using CAD systems, with a reduction in the number of false-negative diagnoses. No statistically significant difference in sensitivity was found between the two CAD systems.

Adult↗
PubMed2006

Effect of dextromethorphan on reference memory assessed in rats by a three-panel runway task.

The effects of dextromethorphan (DM, CAS 6700-34-1), a common over-the-counter cough suppressant, on the reference memory have been investigated by a three-panel runway setup in rats. This study was designed by using a repeated acquisition procedure such as a radialarm maze task or a water maze task. DM (20-40 mg/kg i.p.) produced a significant decrease in the number of errors (pushes made on the two incorrect panels of the three panel gates at four choice points) and latency. Systemically administered scopolamine (CAS 114-49-8) (1 mg/kg i.p.) impaired the performance on both parameters. DM (40 mg/kg i.p.) was effective in reversing the reference memory deficit induced by administration of scopolamine. DM acts as a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptors. Our results suggest that inhibition of NMDA receptors by DM supports its potential positive properties. This finding might present an oppurtunity for the evaluation of this old antitussive drug.

Animals↗
PubMed1999

Deletion 7q in uterine leiomyoma: fluorescence in situ hybridization characterization on primary cytogenetic preparations.

Deletions of the long arm of chromosome 7 constitute one of the most common clonal chromosomal changes associated with uterine leiomyoma cells. Recently, the molecular cytogenetic refinement of 7q deletions in two myoma-derived cell lines, with the use of a panel of 39 ordered 7q DNA probes corresponding to 87 genetic markers, showed results in line with those obtained by loss of heterozygosity (LOH) analysis. Referring to this panel, we extended fluorescence in situ hybridization (FISH) analysis on primary cytogenetic preparations from three myomas with del(7q), thereby avoiding cell passages. This was fundamental in the maintenance of cells with del(7q) in the two cases showing mosaicism (i.e., the presence of an extra normal clone), which are prone to lose the abnormal clone in the very early passages. The data obtained, together with previously published findings on the two leiomyoma-derived cell lines, indicated a commonly deleted region of 11 cM. If the fact that the presence of normal cells may interfere with LOH analysis is taken into account, the FISH approach seems to be a reliable complementing tool for refining the deletion and analyzing the smallest overlapping region in cases with both normal and del(7q) cells.

Chromosome Deletion↗
PubMed2001

Hepatitis C virus testing of plasma pools by nucleic acid amplification technology: external quality assessment.

BACKGROUND AND OBJECTIVES: Since 1 July 1999, in accordance with European regulations, only batches of blood products obtained from plasma pools tested and found to be non-reactive for hepatitis C virus (HCV) RNA are being released. As monitoring the performance of manufacturers involved in plasma pool testing is important to ensure reliable amplification techniques, the Istituto Superiore di Sanità, as the Italian regulatory authority, organized an external quality assessment study. MATERIALS AND METHODS: A reference HCV RNA panel calibrated in international units (IU) was sent to each participant to be tested according to the validated procedure they routinely used in plasma pool testing. The panel consisted of 20 coded samples, four of which were obtained from a negative plasma pool. The remaining 16 samples, prepared by diluting the national reference preparation (ISS HCV RNA 0498), represented four half-log dilution series, each consisting of four samples containing 100, 32, 10 and 3.2 IU/ml of HCV RNA. RESULTS: The overall performance of the laboratories was very satisfactory. All laboratories correctly identified the negative samples. The 100- and 32-IU/ml samples were both detected in 98.4% of the assays, while the 10- and 3.2-IU/ml samples were detected in 73.4 and 50.0% of the assays, respectively. No substantial differences were observed between in-house procedures and commercial kits. CONCLUSION: This external quality assessment study showed that manufacturers of blood products have reached a high level of proficiency that fully complies with the European Pharmacopoeia requirements. This finding is reassuring in the context of the safety of blood products.

Blood Specimen Collection↗
PubMed1989

Observations on phage-typing of Clostridium difficile: preliminary evaluation of a phage panel.

Of the various methods now employed to type Clostridium difficile, the performance of the phage-typing, as proposed by Sell et al., was investigated on a large collection of isolates from various local epidemiological settings. Because those isolates appeared in preliminary trials mostly resistant to the reference phages, the panel was enlarged by including newly isolated phages. The new set was redundant but better suited to the purpose: out of 287 phage sensitivity patterns 8.4% only were resistant in comparison to the 67.6% resistant to the reference one.

Bacteriophage Typing↗
PubMed1988

Observer variation in the pathologic diagnosis of malignant lymphoma in Canada.

Biopsies from "poor prognosis" non-Hodgkin's lymphomas were studied to assess diagnostic variations among pathologists. The original diagnosis and the diagnoses of a nationwide panel of local reference pathologists (LRPs) from 104 cases were reviewed and the technical quality of each biopsy evaluated. Using a modified Rappaport classification, there was agreement in 57% of cases among the panel. This increased to 84% when diagnoses were grouped according to Working Formulation grades. Of the 90 cases in which a comparison of the contributing pathologist's diagnosis and the most common panel diagnosis was possible, there was exact agreement in 51% (kappa = 0.311) of cases and agreement regarding WF grade in 68% (kappa = 0.318). Major panel disagreements occurred in 26 (25%) cases, involving the distinction of metastatic anaplastic carcinoma or Hodgkin's disease from non-Hodgkin's lymphoma in 17 cases and follicular versus diffuse architecture in 16 (overlap present). The contributing pathologist had a major disagreement with the panel in 18 cases (20%), of type and frequency similar to those within the panel itself. Poor fixation (complete or partial) was present in 49 cases (47%); this resulted in significantly fewer majority agreements than in the well-fixed group (25% versus 60%, P = 0.020) and also increased rates of disagreement in the diagnosis of lymphoma versus anaplastic carcinoma. Thus improvements in the technical quality of biopsy material could further improve the diagnostic accuracy of lymphoma diagnosis.

Female↗
PubMed1987

Status displays in automated assembly.

The rapid automation of automotive body assembly operations has resulted in a proliferation of the process steps to be monitored and displayed, thereby making the task of the worker more complex. The progression of assembly and associated machine cycling is controlled by programmable logic controllers whose states are displayed on control panels. The significance of the interface between a worker and several panels used in automated assembly is pointed out. Practical problems with the traditional methods of panel design are discussed. The design and layout of select aspects of such control panels are reviewed with examples in reference to six criteria for panel layout.

Journal Article↗
PubMed2004

Guidelines for critical care medicine training and continuing medical education.

OBJECTIVE: Critical care medicine trainees and faculty must acquire and maintain the skills necessary to provide state-of-the art clinical care to critically ill patients, to improve patient outcomes, optimize intensive care unit utilization, and continue to advance the theory and practice of critical care medicine. This should be accomplished in an environment dedicated to compassionate and ethical care. PARTICIPANTS: A multidisciplinary panel of professionals with expertise in critical care education and the practice of critical care medicine under the direction of the American College of Critical Care Medicine. SCOPE: Physician education in critical care medicine in the United States should encompass all disciplines that provide care in the intensive care unit and all levels of training: from medical students through all levels of postgraduate training and continuing medical education for all providers of clinical critical care. The scope of this guideline includes physician education in the United States from residency through ongoing practice after subspecialization. DATA SOURCES AND SYNTHESIS: Relevant literature was accessed via a systematic Medline search as well as by requesting references from all panel members. Subsequently, the bibliographies of obtained literature were reviewed for additional references. In addition, a search of organization-based published material was conducted via the Internet. This included but was not limited to material published by the American College of Critical Care Medicine, Accreditation Council for Graduate Medical Education, Accreditation Council for Continuing Medical Education, and other primary and specialty organizations. Collaboratively and iteratively, the task force met, by conference call and in person, to construct the tenets and ultimately the substance of this guideline. CONCLUSIONS: Guidelines for the continuum of education in critical care medicine from residency through specialty training and ongoing throughout practice will facilitate standardization of physician education in critical care medicine.

Clinical Competence↗