Pollen-monitoring: between analyst proficiency testing

This study presents the results of a Europe-wide training and Quality Control (QC) exercise carried out within the framework of the European Aerobiology Society’s QC Working Group and European COST Action FA1203 entitled “sustainable management of Ambrosia artemisiifolia in Europe (SMARTER)” with the aim of ensuring that pollen counters in Europe are confident in the identification of Ambrosia pollen grains. A total of 69 analysts from 20 countries examined a test slide by light microscopy, which contained Ambrosia pollen and pollen from other Asteraceae that could be recorded in the atmosphere at the same time of year (i.e. Artemisia, Iva, and Xanthium). Daily average pollen concentrations produced by individual participants were compared with the assigned value and the bias was measured by z-score. Both the assigned value and standard deviation for proficiency testing were calculated following the consensus value principle (ISO13528:2005) from the results reported by all the participants in the test. It took a total of 531 days from when the exercise commenced until all 69 analysts reported their results. The most outliers were reported for Artemisia pollen concentrations followed by Xanthium and Iva. The poor results for Artemisia and Xanthium were probably caused by low concentrations on the test slide leading to larger bias due to the unequal distribution of pollen over the microscope slide. Participants performed the best in identifying and quantifying Ambrosia pollen. Performing inter-laboratory ring tests with the same sample is very time consuming and might not be appropriate for large-scale proficiency testing in aerobiology. Pollen with similar morphology should be included in the education process of aerobiologists.     

Canadian experience in cytology proficiency testing

The mandatory Laboratory Proficiency Testing Program (LPTP) of the province of Ontario as applied to cytology laboratories is briefly described. LPTP evaluates reporting of test slides to identify laboratories that have deficiencies. Such laboratories receive an on-site visit, followed by recommendations on means of improvement (especially educational) and subsequent monitoring. Most of the 18 cytology laboratories visited to date have shown an improved level of performance on later tests.     

Sir Francis Galton and proficiency testing in cytopathology

Data from the National Cytology Proficiency Testing Update show that as of January 31, 2006, 9% of 12,786 examinees failed the test on the first attempt. For the second attempt, the failure rate among those who had initially failed remained surprisingly similar, 10%, although common sense would dictate that it should be much higher among those who have already failed the test once and should have lower professional skills. What is the reason for this remarkable improvement in performance? There is a simple explanation: this is a statistical phenomenon, known as "regression toward the mean." Two groups of examinees earn failing scores during proficiency testing: those whose skills are really insufficient and those who are competent but who achieved lower scores due to random variation in the test results. The latter, "misclassified" examinees subsequently "regress" toward the mean during the second test; that is, their test results become more commensurate with their genuine skills. Since the failure rates of all participants during the first and second attempts were similar, we must assume that the majority of the examinees who failed on the first attempt fall into the second, misclassified group, and only a minority have truly insufficient skills.     

Airborne fungal spore monitoring: between analyst proficiency testing

Aerobiologia - This study presents the results of a Europe-wide training and Quality Control (QC) exercise carried out within the framework of the European Aerobiology Society’s QC Working...     

Scientific issues related to the cytology proficiency testing regulations

The member organizations of the CETC feel strongly that there are significant flaws associated with the proposed proficiency test and its implementation. The most immediate modifications include lengthening the required testing interval, utilizing stringently validated and continuously monitored slides, changing the grading scheme and changing the focus of the test from individuals to laboratory level testing, as described above. Integration of new computer-assisted and location-guided screening technologies into the testing protocol is necessary for the testing program to be compliant with the current CLIA law. The regulation also needs to be flexible enough to accommodate new technologies that are implemented in laboratory practice, education and administration of the test. The changes recommended in this document address the most immediate technical and scientific concerns with the current implementation of PT for gynecologic cytology. The CETC will be submitting a subsequent document, following full review of the current regulations, with recommendations for changes, justifications and impact.     

Laboratory performance in a food microbiology proficiency testing scheme

Results from two shipments in a proficiency testing scheme in which almost 200 food microbiology laboratories participated are summarized. Freeze-dried mixtures of bacteria were used as simulated food samples. Four and six samples, respectively, were examined. The statistical procedures used to evaluate the performance of participating laboratories are described. It is shown that laboratories which had been in the scheme for a long time perform, on average, better than those that had been in the scheme for a short time. The former laboratories produced fewer false and outlying results, and were more accurate and precise in their determinations.     

Laboratory performance in a food microbiology proficiency testing scheme.

Results from two shipments in a proficiency testing scheme in which almost 200 food microbiology laboratories participated are summarized. Freeze-dried mixtures of bacteria were used as simulated food samples. Four and six samples, respectively, were examined. The statistical procedures used to evaluate the performance of participating laboratories are described. It is shown that laboratories which had been in the scheme for a long time perform, on average, better than those that had been in the scheme for a short time. The former laboratories produced fewer false and outlying results, and were more accurate and precise in their determinations.     

阪崎肠杆菌能力验证样品均匀性和稳定性的研究

目的制备出以脱脂奶粉为基质的均匀性好、稳定性强的阪崎肠杆菌(Enterobacter sakazakii)能力验证样品。方法研究奶粉基质的粒度、奶粉和菌粉的混合比例,得到阪崎肠杆菌能力验证样品的最佳均匀性条件;研究包装形式及贮存温度对样品稳定性的影响,得到阪崎肠杆菌能力验证样品的最佳稳定性条件。结果要保证样品足够均匀,奶粉最佳粒径范围为120μmD180μm,1 g菌粉最多与300 g奶粉进行混合;贮存温度对样品稳定性有较大影响,高温明显降低样品稳定性;真空包装可以显著提高样品稳定性。结论以奶粉为基质的阪崎肠杆菌能力验证样品的制备能够更准确地考查乳品微生物检验人员的检测水平,为国内微生物能力验证水平的提高奠定了基础。     

Simple bacterial preservation medium and its application to proficiency testing in water bacteriology.

A medium composed of nutrient broth, 1.8% boric acid, and 1% sodium chloride at pH 7.0 was shown to maintain the stability of Escherichia coli cultures for up to 10 days at room temperature. By using this preservation medium for preparing a simulated sample a successful proficiency test survey in water bacteriology was conducted.     

Predicting the stability of freeze-dried Fusobacterium mortiferum proficiency testing samples by accelerated storage tests

Short-term, thermal degradation tests were performed at elevated temperatures of 55, 42, and 35 °C with freeze-dried proficiency testing samples of F. mortiferum. The loss of viable numbers of organisms was predicted for the samples at lower storage temperatures of 27.5 and 4 °C by applying calculated K values for the three elevated temperatures to the Arrhenius relationship. The predicted K values were within 1 SE of the K values obtained by least-squares analysis of the experimental data for the two lower storage temperatures. Application of accelerated storage tests for predicting stability at storage temperatures offers a number of benefits, including cost benefits, in assessing the stability of freeze-dried bacterial preparations used in proficiency testing programs.     

Evaluation of proficiency testing as a method of assessing competence to screen cervical smears

Evaluation of proficiency testing as a method of assessing competence to screen cervical smears Regular proficiency testing of pathologists and cytotechnologists who undertake the analysis of cervical smears has been carried out in cytology laboratories in the North Thames (West) Region since 1989. The protocol followed is one that has been adopted nationally. Since the scheme started, laboratory personnel from 17 cytology laboratories in the Region have participated and seven rounds of testing have been completed. Nine hundred and seventy-one tests were carried out and a pass rate of 96.4% was recorded. Two hundred and forty-seven cytologists took the test on at least one occasion and 63 cytologists took part in all seven rounds. Our results indicate that proficiency testing is capable of detecting cytologists who consistently perform below an acceptable standard and require retraining. They also show that even the most competent screeners can miss an abnormal smear. Seven cytologists who had proved their competence to screen on six occasions, missed an abnormal smear on the seventh, despite the fact that they were screening under test conditions when their vigilance should have been at its peak. Our findings indicate that false-negative reporting will inevitably occur during manual screening, and emphasize the need for further research into the causes and prevention of screening error. Evaluation des tests d'aptitude comme méthode d'appréciation de la compétence à lire les frottis cervico-utérins de dépistage Le passage régulier de tests d'aptitude pour les pathologistes et les cytotechniciens qui prennent en charge l'analyse de frottis cervico-utérins est utilisé dans les laboratoires de cytologie de la région North Thames (West) depuis 1989. Le protocole choisi est l'un de ceux qui ont été adoptés au niveau national. Depuis le début de ce programme, 7 sessions de tests ont été organisées et le personnel de 17 laboratoires de cytologie de la région a participé. Neuf cent soixante et onze tests ont été pratiqués et le taux de participation enregistré est de 96,4%. Deux cent quarante sept cytologistes ont fait le test au moins une fois et 63 cytologistes ont passé les 7 sessions de tests. Nos résultats indiquent que les tests d'apitude sont capables d'identifier les cytologistes qui ont besoin d'une formation car leur résultats aux tests sont régulièrement en dessous des standards acceptables. Ils montrent également que même les “screeners” les plus compétents peuvent passer à côté d'un frottis anormal. Sept cytologistes ayant montré leur compétence pour la lecture des frottis de dépistage sur 6 tests n'ont pas été capable de détecter un frottis anormal sur le septième test, bien que cette lecture ait été faite dans des conditions de test où leur vigilance aurait dû être à son maximum. Ces résultats indiquent qu'il est impossible d‘éviter les faux négatifs au cours du “screening manuel” et confirment la n?essité de poursuivre les recherches sur les causes des erreurs de lecture et sur leur prévention. Die Ergebnisse der Laistungstests als Grundlage für die Fähigkeit gynäkologische Abstriche auszuwerten Regelmässige Leistungstests von Zytopathologen und Zytotechnikerinnen beim Auswerten gynäkologischer Abstriche wurden seit 1989 in den Labors der Nord-Themse Region durchgeführt. Das Testprotokoll entspricht dem landesweit angewandten. Inzwischen nahmen 17 Labors an insgesamt 7 Testrunden teil. Die Gesamtzahl der Tests beträgt 971 wobei 96,4% der Teilnehmer die Tests bestanden. 247 Teilnehmer nahmen an zumindest einem Test, 63 an allen sieben teil. Die Auswertungen ergaben, dass auf diese Weise Zytologen mit unterdurch schnittlicher Leistung identifiziert und einem Zusatztraining zugeführt werden können. Sie zeigen aber auch, dass selbst die Erfahrendsten gelegentlich positive Befunde übersehen. Sieben Teilnehmer begingen diesen Fehler nach sechs fehlerfreien Durchgängen beim siebten Test trotz der bekannten Testsituation. Dies bedeutet, dass Fehler bei nichtautomatischer Auswertung unvermeidbar sind. Die Ursachenforschung muss weitergeführt werden.     

Competency and Risk-relativity

In this paper I discuss the view that the appropriate concept of competence is a decision-relative one: that a person may be competent to make one decision but not another. The argument that I present is that neither of the two competing theories supporting the decision-relative approach, internalism and externalism, can provide a coherent explanation of why a person's competence should be thought to be relative to a particular decision. On the one hand, internalism, which regards competence as exhaustively a matter of the person's understanding, fails to identify the specific skills or content that would warrant linking a specific decision with competence, and thus cannot provide an account of decision-relative that parallels task-relative. On the other hand, externalism, which regards competence as a matter of the person's understanding in relation to external elements such as risk, cannot adequately defend why a person's competence to make a decision should 'track' the level of probable harm that results from the decision.     

Quality control in cytopathology. A system for simultaneous monitoring of accuracy and education and for proficiency testing

Because of its very nature, cytopathology has not lent itself well to quality control. At the University of North Carolina, we practice an internal quality control system based on peer review, interprofessional dialogue and utilization of follow-up information. Recently reported cytology specimens are rescreened and correlated with related surgical specimens. This review is summarized in a weekly conference, at which retrospective accuracy judgments are made for each case under the supervision of the medical director and head cytotechnologist. Diagnostic accuracy is thus monitored. Accuracy is also improved since education is simultaneously monitored. A practical proficiency-testing program built into this system is described.