Results: Fourteen trained allergy nurses participated in the proficiency testing. More than 95 % of the nurses, gener‑ ated coefficient of variation less than 40 %, and for around 35 % of testers the CV were below 20 % based on wheal area. Regarding the linearity (coefficient of regression), only two nurses produced tests with a value below 0.85. On the contrary, 79 % of testers demonstrated a coefficient of regression >0.95. Depending on the gentleness of the prick procedure, the inter‑nurse variability in wheal area varied more than twofold corresponding to a 10‑doubling of hista‑ mine concentration. This would never have been detected without using a proficiency testing system.
In the past, proficiency testing programs for antimicrobial susceptibility testing have focused primarily on testing accu- racy. However, equally important is assessment of reporting accuracy. Although there were few testing errors with the S. enterica subsp. enterica serovar Enteritidis and S. saprophyticus isolates, there were multiple reporting errors with these organ- isms. NCCLS guidelines state that certain antimicrobial agents should not be tested or reported for Salmonella species be- cause they may give false-susceptible results. Nonetheless, 136 laboratories tested and reported antimicrobial agents that are inappropriate for Salmonella infections (Table 1). Although salmonellae are tested with the same set of disks or MIC panels used for other gram-negative enteric organisms, labo- ratories must ensure that only the appropriate antimicrobial agents are reported. Some antimicrobial agents, such as the aminoglycosides, are always inappropriate; on the other hand, extended-spectrum cephalosporins, such as cefotaxime and ceftriaxone, are appropriate to report for extraintestinal Sal- monella infections. Thus, it is important to test and report these agents selectively.
It can be seen from the results of the first two rounds of the proficiency testing scheme that laboratories performing the leptospirosis MAT quite often report incorrect results. Some- times participating laboratories reported false-negative results, incorrectly identified the serogroup for which a sample was positive, or failed to identify a positive sample as positive for any serogroup. Participants also reported widely varying titers for a particular sample tested with a specific serovar. Contam- ination, misidentification, and deterioration of antigen cultures are among the factors that can contribute to diagnostic errors by MAT. Laboratories can reduce errors by carefully monitor- ing the identities of cultures and periodically seeking replace- ment cultures from reference laboratories.
The New York State Public Health Law requires all clinical laboratories and blood banks conducting tests on specimens collected within New York State to hold a state clinical labo- ratory permit, unless the tests are conducted as an adjunct to a physician’s medical practice (physician office laboratory). In response to a 1964 legislative mandate, the New York State De- partment of Health initiated an overt proficiency testing (OPT) program as one method of monitoring the overall quality of testing performed by state permit-holding clinical facilities. The program, as of 1998, has grown to include almost 1,000 clinical facilities, both within New York State and in over 30 other states. Of these, 188 hold permits in medical mycology to isolate and identify either yeast-like potential pathogens only (limited permit) or all fungi and aerobic actinomycetes (gen- eral permit) which may be recovered from clinical specimens. After learning of widely publicized problems found in the screening of Papanicolaou smears in cytopathology laborato- ries, Congress enacted the Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88). The statute and enabling regulations initially required, in part, that all sites conducting laboratory tests on human specimens must participate in fed- erally approved OPT programs. While the regulatory burden has been lightened over the years, current CLIA ’88 regula- tions require approximately 40% of all federally registered test facilities to participate in one of 20 OPT programs approved by the Health Care Financing Administration. Proficiency testing has gained wide acceptance as a regulatory tool; the mainte- nance of clinical laboratory operating licenses at state and federal levels are chiefly dependent upon successful OPT per- formance.
At present, the most commonly used difference significance test method contains Z test, t test, F test and chi-square etc. . Statistically, the probability distribution of the most continuous random variables is normal distribution which our daily measurement result basically all obeyed. Proficiency testing analysis is based on the basis of test results is normal distribution . In the statistical analysis of proficiency testing data, t test can be carried out on the samples while the samples can be divided into two groups in order to verify whether there is a significant difference between two samples data, furthermore, if the samples are grouped in two groups above, the F test can be carried out. Accordingly, the test results of the example in this paper can be divided into four groups according to the different test methods, thus, the F test can be adopted to the sample data.
The accuracy of antimicrobial susceptibility data submitted by microbiology laboratories to national and international surveillance systems has been debated for a number of years. To assess the accuracy of data submitted to the World Health Organization by users of the WHONET software, the Centers for Disease Con- trol and Prevention distributed six bacterial isolates representing key antimicrobial-resistance phenotypes to approximately 130 laboratories, all but one of which were outside of the United States, for antimicrobial susceptibility testing as part of the World Health Organization’s External Quality Assurance System for Antimicrobial Susceptibility Testing. Each laboratory also was asked to submit 10 consecutive quality control values for several key organism-drug combinations. Most laboratories were able to detect methicillin (oxacil- lin) resistance in Staphylococcus aureus, high-level vancomycin resistance in Enterococcus faecium, and resis- tance to extended-spectrum cephalosporins in Klebsiella pneumoniae. Many laboratories, particularly those using disk diffusion tests, had difficulty in recognizing reduced susceptibility to penicillin in an isolate of Streptococcus pneumoniae. The most difficult phenotype for laboratories to detect was reduced susceptibility to vancomycin in an isolate of Staphylococcus epidermidis. The proficiency testing challenge also included a request for biochemical identification of a gram-negative bacillus, which most laboratories recognized as Enterobacter cloacae. Although only a small subset of laboratories have submitted their quality control data, it is clear that many of these laboratories generate disk diffusion results for oxacillin when testing S. aureus ATCC 25923 and S. pneumoniae ATCC 49619 that are outside of the acceptable quality control range. The narrow quality control range for vancomycin also proved to be a challenge for many of the laboratories submitting data; approxi- mately 27% of results were out of range. Thus, it is important to establish the proficiency of laboratories submitting data to surveillance systems in which the organisms are tested locally, particularly for penicillin resistance in pneumococci and glycopeptide resistance in staphylococci.
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The WWARN QA/QC programme is a dynamic pro- gramme for the distribution of certified reference stan- dards and proficiency testing samples for anti-malarial drug measurement. It will facilitate clinical pharmacoki- netic and in vitro sensitivity studies around the world. The proficiency testing programme is designed as a cooperative effort to help participating laboratories assess their ability to carry out drug analysis, resolve any potential problem areas and to improve their results - and, in so doing, to improve the quality of anti-malarial pharmacokinetic data published and shared with WWARN. To ensure the quality of pharmacokinetic data, it is important that laboratories use validated and accurate methods, but equally important that results are compared with other laboratories. By utilizing the same source of standards for all laboratories, it is possible to minimize bias arising from poor quality reference stan- dards. By providing anti-malarial drug standards from a central point, it is possible to lower the cost of these standards. This process both assesses and empowers.
ABSTRACT The unprecedented 2015 Ebolavirus (EBOV) outbreak in West Africa was declared a public health emergency, making diagnosis and quality of testing a global issue. The accuracy of laboratory diagnostic capacity for EBOV was assessed in 2014 to 2016 using a proﬁciency testing (PT) strategy developed by the Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) in Bio- security. Following a literature search, EBOV-speciﬁc gene targets were ranked ac- cording to the frequency of their use in published methods. The most commonly used gene regions (nucleoprotein [NP], glycoprotein [GP], and RNA-dependent RNA polymerase [L]) were selected for the design of in vitro RNA transcripts to be in- cluded in the simulated EBOV specimens used for EBOV detection with PCR-based assays. Specimens were tested for stability and found to be stable on long-term storage (1 year) at ⫺ 80°C and on shorter-term storage in lyophilized form (1 week at ambient temperature and a subsequent week at ⫺ 80°C). These specimens were used in three EBOV PTs offered from April 2014 to March 2016. In the ﬁrst and third PTs, all laboratories (3/3 and 9/9, respectively) correctly identiﬁed specimens contain- ing EBOV RNA transcripts, while in the second PT, all but one laboratory (5/6) cor- rectly conﬁrmed the presence of EBOV. The EBOV PT panel was useful for ensuring the competency of laboratories in detecting EBOV in the absence of readily available clinical samples. The simulated EBOV specimen was safe, stable, and reliable and can be used in lyophilized form for future EBOV PT programs, allowing simplicity of transport.
Language testing did not alter self- reported Spanish pro ﬁ ciency or antic- ipated interpreter use. We previously reported that a substantial number of residents inaccurately assess their Spanish skills when compared with objective testing (K.C.L., D.A.T., J.D.C., E.M., S.A.R., R.F.H., E.F.K., J.F., B.E.E., unpublished data, 2011). In this study, of 18 residents who reported themselves to be pro ﬁ cient or ﬂ uent, 33% tested at a “ not pro ﬁ cient ” level, and 78% tested at a “ not highly pro ﬁ cient ” level (K.C.L., D.A.T., J.D.C., E.M., S.A.R., R.F.H., E.F.K., J.F., B.E.E., unpublished data, 2011). Our ﬁ nding that self-assessment rarely changed, even when inconsistent with objective testing results, may help ex- plain the modest impact of language testing. In particular, it provides a po- tential explanation for the ﬁ nding that testing did not change nonpro ﬁ cient res- idents ’ comfort using Spanish in complex or medicolegal scenarios. Those who be- lieved themselves pro ﬁ cient before test- ing continued to trust their abilities, regardless of test results. In addition, many providers reporting clinical Span- ish use did so despite self-reported lack of pro ﬁ ciency. Con ﬁ rmation of lack of
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Washback can be defined as how a test influences the activities which go on in a language classroom before testing, or what Alderson and Wall describe as something that ‘compels teachers and learners to do things they would not necessarily otherwise do because of the test’ (Alderson and Wall 1993, p.115, their emphasis). Washback can be positive and negative in terms of the types of changes in a curriculum that a test can induce. For example, incorporating spoken interaction into a test is likely to lead to washback in the classroom, and encourage teachers and learners to place more emphasis on the skills involved in dialogue, listening comprehension and creating appropriate spontaneous utterances. But washback can also be detrimental to learners’ competences, by focussing for example on inauthentic aspects of a test or indeed on how to pass the test itself. In a wide-ranging review of the empirical investigation of the washback of standardised EFL tests on EFL education in Korea, Choi shares survey data on the washback in elementary, secondary and university language classrooms. For instance, one specific aspect of the negative test washback in
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later used for qualitative studies: when educators or re- searchers need to investigate learners’ particular char- acteristics (e.g., speech error patterns) in the EI tasks. It is also possible to conduct similar qualitative stud- ies, such as examining the relationship between learn- ers’ test performance and their learning experience. In fact, the findings obtained through such qualitative analyses are highly important and necessary for fur- ther testing and grading procedure refinement. Past work in EI testing has identified key features that EI test items need to address: (1) The length (whether con- trolled by morae, syllables, or words) must exceed partic- ipants’ short-term memory capacity, thus precluding rote repetition. (Jessop et al., 2007). (2) Lexical and morpho- logical features must be carefully chosen or else items may be too easy or too difficult for learners to repeat (Tomita et al., 2009). (3) Target features should ideally be placed in the middle position of the sentence (Erlam, 2006). Satis- fying these constraints is crucial for producing optimal EI items (Christensen et al., 2010). EI items must also tar- get salient grammatical features that reflect the goals of the learners at various levels, curriculum designers, instructors, and evaluators. Taking all these requirements into consid- eration when developing EI items is daunting.
The EQA program was developed and implemented after completion of the regional training and had two components: an external proficiency testing (EPT) program and a validation process. Since some of the laboratories had no previous experience with EQA, it was important to ensure that the basic factors that were used to guide this process were understood by all participants, namely: (i) the level of challenge appropriate to participating laboratories; (ii) use as an edu- cational tool to deliver new information and to assist with problem solving when difficulties were encountered; (iii) a means of evaluation for “routine” laboratory procedures; (iv) monitoring of the performance of reagents, technical precision and accuracy, and clerical processes (including accurate documentation), as well as identifying staff training opportunities; and (v) the provision of timely feed- back to all participants, supporting continuous improvement rather than focusing on “testing failure.”
Background and Objective: Proficiency testing schemes as a part of quality system in clinical and research laboratory centers provides the opportunity to evaluate the quality of test results. In this paper, we try to introduce the proficiency testing schemes as a useful method for achieving standardization and homogenization of test results in clinical and research laboratory centers.
ceptible” by BMD testing performed at the Project ICARE central laboratory. Previous proficiency testing surveys have documented carbapenem testing problems (7, 12, 17, 30). However, the extent of the false resistance reported in this study by so many laboratories using a variety of different meth- ods is disturbing, especially for isolates of Enterobacteriaceae. For many of the isolates, the imipenem MICs were ⱕ1 g/ml by Project ICARE BMD testing but ⱖ8 g/ml by hospital laboratory testing. The high number of major errors was not reproducible in the CDC laboratory, even when the same test- ing systems and the same isolates were used. In the accuracy of test methods study, with the exception of imipenem testing of P. aeruginosa by the Vitek system, the five test methods studied produced few very major or major errors. More errors (espe- cially minor errors) occurred with P. aeruginosa than with iso- lates of Enterobacteriaceae, and most minor errors were within one doubling dilution of the BMD result (where evaluable) or within 3 mm of the categorical breakpoint. In this study, more isolates of P. aeruginosa had MIC test results that clustered around the carbapenem breakpoints than did the isolates of Enterobacteriaceae. This could explain the higher percentage of errors observed for P. aeruginosa.
If literacy is socially constructed and consequently part of one’s identity, then the testing of it, according to Street 25 , is predisposed to bias. As a result, Street argues against the use of any form of standardized tests. His reasoning is that within any given standardized exam, there are cultural contexts which privilege only a certain few. Willis 35 agrees with Street on this point, suggesting that reading comprehension tests in particular are a product of dominant groups in society. Willis contends that these groups embed their own ideas of the world into the tests purposely to further advance their belief systems and culture.
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In today’s globalised, technology-supported learning environment it would seem the prudent provider would capitalise on engaging students in multimediated, interactive social- networked virtual learning communities. The availability of this approach, that is able to connect ESL/EFL learners around the world, stands to revolutionise English language learning through its facilitation of meaningful communicative interactions. It allows self- assessment to be built-in and the promotion of positive washback through the construction of learning environments that involve real-life, purposeful tasks. In turn, such an approach facilitates the design of authentic tasks that may be embedded in project- and problem-based learning where students need to communicate to collaborate. NETPAW has clear goals to promote online English language learning and improve English proficiency. It works towards achieving these goals by exemplifying such practices in their ability to reducing paper usage and minimise the use of other non-renewable energies and thus contribute to sustainability. While this exploration of tests shows a trend towards language testing online, testing systems by nature pay less attention to the need for positive washback and improving language pedagogy and learning. However, both TOEFL (iBT) and PTE display impressive information on their online testing approaches, content and marking criteria. Supporting information is available for test preparation and internet-searches show a wealth of additional resources, including videos on YouTube. Major test developers continue to research their tests to consider issues that may impact on uptake such as scope and validity and reliability (ETS, 2007; 2008a; 2008b), and in a business sense they need to respond to economic issues. De Prada (1997) alerts one to the fact that international
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A third feature of interest is segregation. Segregation means a change in the chemical composition of the melt during solidification. Under ideal conditions, the cast object should have a homogeneous composition after solidification. However, this involves diffusion processes that require a certain amount of time that is not provided for in Pt alloys, which by nature solidify very quickly under typical casting conditions. As a consequence, the high melting elements of the alloy concentrate in the dendrite cores while the lower melting elements concentrate in the remaining melt. The actual segregation can be obtained from phase diagrams and depends on the cooling rate and alloy composition. Low melting elements such as Ga or In that were added to some alloys in this study showed strong segregation to the liquid phase. These elements therefore concentrate in the interdendritic regions. The inhomogeneous composition of the cast part is shown most clearly in Figure 1 by the different shades of grey inside the grains. The dendrites appear bright in back- scattered electron images, because they are rich in elements of high atomic mass, namely Pt and Ru that precipitate first from the melt. The elements of low atomic mass that concentrate in the interdendritic regions make these regions appear darker. The segregation appears to be unaffected by HIP (18). It was demonstrated by thermodynamic simulations that the segregation depends strongly on the curvature of the liquidus and solidus surface (24).
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Of the enucleation specimens tested for which there were associated pathology data, the proportion of Class 1 patients shifted to be predominately Class 1B vs. Class 1A, and the proportion of Class 2 tumors was also in- creased compared to the total clinical population. Given the significantly increased LBDs and thicknesses of enu- cleation specimens (i.e. those that necessitated removal of the globe), an increase in Class 2 and Class 1B tumor classification is not unexpected. Importantly, there were no significant differences between Class 1A and 1B tu- mors in terms of cell morphology, ciliary body involve- ment, or extraocular extension, underscoring the utility of molecular testing to delineate risk in these tumors that otherwise share similar pathologic features. Overall, the pathology and molecular class data in our clinically tested cohort reflect published reports that greater LBD and tumor thickness tend to be clinicopathologic features associated with more aggressive tumors [9, 20, 22, 23], and these riskier phenotypes are most frequently seen in Class 1B or Class 2 tumors. An advantage of gene ex- pression profiling is that it reflects objective, intrinsic tumor biology, whereas measurements of LBD in particu- lar can be subjective due to variation between observers and in techniques used for size measurement . Add- itionally, cytopathologic analysis can be impaired by a high rate of insufficient cellularity from FNABs . Several Table 4 Statistical comparisons between molecular class and tumor pathology in enucleated cases
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Malaria parasite infections that are only detectable by molecular methods are highly prevalent and represent a potential transmission reservoir. The methods used to detect these infections are not standardized, and their operating characteristics are often unknown. We designed a proficiency panel of Plasmodium spp. in order to compare the accuracy of parasite detection of molecular protocols used by labs in a clinical trial consortium. Ten dried blood spots (DBSs) were assembled that contained P. falciparum, P. vivax, P. malariae, and P. ovale; DBSs contained either a single species or a species mixed with P. falciparum. DBS panels were tested in 9 participating laboratories in a masked fashion. Of 90 tests, 68 (75.6%) were correct; there were 20 false-negative results and 2 false positives. The detection rate was 77.8% (49/63) for P. falciparum, 91.7% (11/12) for P. vivax, 83.3% (10/12) for P. malariae, and 70% (7/10) for P. ovale. Most false-negative P. falciparum results were from samples with an estimated <5 parasites per l of blood. Between labs, accuracy ranged from 100% to 50%. In one lab, the inability to detect species in mixed-species infections prompted a redesign and improvement of the assay. Most PCR-based protocols were able to detect P. falciparum and P. vivax at higher densities, but these assays may not reliably detect parasites in samples with low P. falciparum densities. Accordingly, for- mal quality assurance for PCR should be employed whenever this method is used for diagnosis or surveillance. Such efforts will be important if PCR is to be widely employed to assist malaria elimination efforts.
As Wray (2002) rightly emphasizes, collocations are of particular importance for learners who wish to achieve a high degree of competence in the second language, but they are also important for learners with less ambitious aspirations, as they enhance not only accuracy but also fluency. Accordingly, teaching collocations should be emphasized in EFL courses at all levels since “the correct usage of collocations contributes greatly to ones’ idiomaticity and nativelikeness” (James, 1998, p. 152). However, in spite of the growing recognition of collocational knowledge as both indispensable and problematic for foreign language learners, it seems that contextualized vocabulary (i.e., collocations) has not received due attention among language teachers and researchers so far, especially in our country. Indeed, a search in the Iranian Research Institute for Scientific Information and Documentation database for research studies done in this area did not yield any results. Accordingly, the current study aimed at investigating the learners’ oral use of collocations and uncovering the relationship between the collocational knowledge and the speaking proficiency, thus adding one more ring to the still chain of the research on lexis in general and of collocations in particular. More precisely, this
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