National Proficiency Testing Research Articles

National Survey on Internal Quality Control for HbA1c Analytical Instruments in 331 Hospital Laboratories of China

The narrow gap of HbA1 value of mass fraction between "normal" (< 6.0%) and "diabetes" (≥ 6.5%) necessitates tight control of inter-assay standardization, assay precision, and trueness. This survey was initiated to obtain knowledge of the current situation of internal quality control (IQC) practice for HbA(1c) in China and find out the most appropriate quality specifications. Data of IQC for HbA(1c) in 331 institutions participating in the national proficiency testing (PT) programs in China were evaluated using four levels of quality specifications, and the percentages of laboratories meeting the quality requirement were calculated to find out the most appropriate quality specifications for control materials of HbA(1c) in China. The IQC data varied vastly among 331 clinical laboratories in China. The measurement of control materials covered a wide range from 4.52% to 12.24% (inter-quartile range) and there were significant differences among the CVs of different methods, including LPLC, CE-HPLC, AC-HPLC, immunoturbidimetry, and others. Among the four main methods, CE-HPLC and AC-HPLC achieved a better precision. As we can see, the performance of laboratories for HbA(1c) has yet to be improved. Clinical laboratories in China should improve their performance with a stricter imprecision criteria.

French national proficiency testing study for the standardisation of the CFU-GM progenitor assay

The Laboratory Controls Division of the French Health Product Safety Agency (ANSM) had organized annual external quality control (EQC) of Hematopoietic Stem Cells (HSC) preparations from 2000 to 2013. From this experience, it appeared that it was necessary to prepare new technical guidelines for the clonogenic assay. Indeed the present guidelines did not give sufficient tools of validation. The analysis of data collected from the EQC allowed to produce recommendations which have been placed in public inquiry for three months in 2013. In order to evaluate these ones, a Proficiency Testing Study was conducted with 29 control laboratories of HSC. To that end, samples of fresh cord blood, culture medium and cell culture procedure were sent to participants. Three conditions were proposed: seeding 200 cells CD34+ per dish (compulsory requirement) with initial cord blood then according to laboratories practices, seeding at another cell concentration and/or after erythrocyte removal. For the reference condition, coefficients of variation are inferior to 40%, while discrepancies vary much more for the two other conditions (with a maximum value of 116.6%). In order to carry on the assessment of erythrocyte removal procedures initiated during this study, we performed additional testing of sedimentation. They have shown that this simple and fast method can be used with reliability but only in intra-laboratory conditions. Alongside, comments received during the public inquiry were studied. The answers were documented by analyzing data from EQC that showed an improvement of reproducibility of results obtained in 2011-2012. Eventually, the recommendations were adjusted according to our studies and will be evaluated by the Committee of biological products of the French Pharmacopoeia. All our results showing that the clonogenic assay can be used reliably to evaluate the quality of hematopoietic grafts should allow to base the publication of these recommendations in early 2014.

Comparison of Immunoassay Screening Tests and LC-MS-MS for Urine Detection of Benzodiazepines and Their Metabolites: Results of a National Proficiency Test

For most diverse purposes, different immunoassay (IA) screening methods are usually used to detect benzodiazepines and their metabolites in urine. In this study, we compared the main IAs used in forensic toxicology (Cloned Enzyme Donor Immunoassay, CEDIA®; Enzyme-Multiplied Immunoassay Technique, EMIT®; Fluorescent Polarization ImmunoAssay, FPIA®; Kinetic Interaction of Microparticles in Solution, KIMS® and Immunochromatographic Techniques, IMC) with liquid chromatography-tandem mass spectrometry (LC-MS-MS). Twelve urine specimens were analyzed by 178 laboratories in Italy that participated in a National Proficiency Test, providing both qualitative and semi-quantitative results. Each IA was evaluated by the parameters: true positive, true negative, false positive (FP), false negative (FN), sensitivity (SENS), specificity (SPEC), positive predictive value, negative predictive value (NPV) and accuracy. SPEC was affected by a high FP rate for all IAs. The lowest SENS and NPV were provided by FPIA due to a high number of FN cases. Comparing IA semi-quantitative data with LC-MS-MS results, an overestimation of benzodiazepine amount is noted. This paper draws attention to the problem of the careless use of IA tests for forensic purposes as they may provide FP and/or FN results that can lead to errors of great severity.

Use of CD157 in FLAER-based assays for high-sensitivity PNH granulocyte and PNH monocyte detection

Recent Flow Cytometric guidelines to detect Paroxysmal Nocturnal Hemoglobinuria (PNH) in white blood cells recommend using FLAER-based assays to detect granulocytes and monocytes lacking expression of GPI-linked structures. However national proficiency testing results continue to suggest a need for improved testing algorithms, including the need to optimize diagnostic analytes in PNH.CD157 is another GPI-linked structure expressed on both granulocytes and monocytes and here we assess its ability to replace CD24 and CD14 in predicate 4-color granulocyte and monocyte assays respectively. We also assess a single tube, 5-color combination of FLAER, CD157, CD64, CD15, and CD45 to simultaneously detect PNH clones in granulocyte and monocyte lineages.Delineation of PNH from normal phenotypes with 4- or 5-color CD157-based assays compared favorably with 4-color predicate methods and PNH clone size data were similar and highly correlated (R(2) >0.99) with predicate values over a range (0.06%-99.8%) of samples. Both CD157-based assays exhibited similar high levels of sensitivity and low background levels in normal samples.While CD157-based 4- and 5-color assays generated closely similar results to the predicate assays on a range of PNH and normal samples, the 5-color assay has significant advantages. Only a single 5-color WBC reagent cocktail is required to detect both PNH granulocytes and monocytes. Additionally, sample preparation and analysis time is reduced yielding significant efficiencies in technical resources and reagent costs. All 4- and 5-color reagent sets stained stabilized whole blood PNH preparations, used in external quality assurance programs.

Use of CD157 in FLAER-based assays for high-sensitivity PNH granulocyte and PNH monocyte detection.

Background: Recent Flow Cytometric guidelines to detect Paroxysmal Nocturnal Hemoglobinuria (PNH) in white blood cells recommend using FLAER-based assays to detect granulocytes and monocytes lacking expression of GPI-linked structures. However national proficiency testing results continue to suggest a need for improved testing algorithms, including the need to optimize diagnostic analytes in PNH. Methods: CD157 is another GPI-linked structure expressed on both granulocytes and monocytes and here we assess its ability to replace CD24 and CD14 in predicate 4-color granulocyte and monocyte assays respectively. We also assess a single tube, 5-color combination of FLAER, CD157, CD64, CD15 and CD45 to simultaneously detect PNH clones in granulocyte and monocyte lineages. Results: Delineation of PNH from normal phenotypes with 4- or 5-color CD157-based assays compared favorably with 4-color predicate methods and PNH clone size data were similar and highly correlated (R2 >0.99) with predicate values over a range (0.06% - 99.8%) of samples. Both CD157-based assays exhibited similar high levels of sensitivity and low background levels in normal samples. Conclusion: While CD157-based 4- and 5-color assays generated closely similar results to the predicate assays on a range of PNH and normal samples, the 5-color assay has significant advantages. Only a single 5-color WBC reagent cocktail is required to detect both PNH granulocytes and monocytes. Additionally, sample preparation and analysis time is reduced yielding significant efficiencies in technical resources and reagent costs. All 4- and 5-color reagent sets stained stabilized whole blood PNH preparations, used in external quality assurance programs. © 2013 Clinical Cytometry Society.

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Aim Expeditious flow cytometry crossmatch (FCXM) assay giving consistent inert-lab results is critical for successful and safe national organ sharing. In order to understand the degree and nature of variability in FCXM testing across Canada, national proficiency testing (PT) program was established. In the 1st PT survey, the focus was on studying the factors that contribute to FCXM result variability. The 2nd survey examined the effects of assay standardization and optimization. Methods Both surveys consisted of 3 sera, 2 donor cells and MESF beads. Donor HLA typing and serum HLA antibody profiles were provided to aid XM interpretation. Questionnaire was sent to obtain specific protocol information. XM data (channel & MESF values) and questionnaire responses were collected from 13 participating labs and analyzed. In survey 1, labs were asked to perform FCXM as per local lab protocol. In survey 2, labs were provided with optimized FCXM protocol (Liwski et al. ASHI 2011), pronase/DNase procedure and common reagents (pronase, DNase, & anti-IgG-FITC). Labs were asked to test FCXM using their own protocols with specific modifications vs optimized FCXM protocol. Results In survey 1, significant inter-lab FCXM result variability was seen. MESF scale was helpful in result comparison. Technique, cell number and serum volume were main factors contributing to observed variation. Pronase use was critical for B cell XM. In PT part 2, the findings showed that standardization (cell number/serum volume and pronase use) significantly improved result consistency. Use of optimized protocol and common α-IgG-FITC further improved results. Optimized assay compared favourably with conventional methods, while decreasing XM time by 1 h. Conclusions Significant variability in FCXM methods and results were seen. Standardization of FCXM protocol improved result concordance. Optimized FCXM protocol will improve risk assessment precision, facilitate equitable national organ sharing and optimize low risk transplant allocation.

Quality assurance for measurements of the radioactivity in the area of the“Horia Hulubei” National Institute for Physics and Nuclear Engineering, IFIN-HH

This paper presents one part of the activities deployed by the Laboratory for Environment and Personnel Dosimetry (LDPM) of IFIN-HH, namely the radiological monitoring of the environment within the Institute's area and its surrounding influence zone, according to the program approved by the National Regulatory Body for Nuclear Activities, CNCAN. The representative reports regard the radioactive content of soil, surface and underground water, cultivated and spontaneous vegetation, aerosols and atmospheric fallout, sediments. The common requirement is that the measured quantities be precise and the reported values be reliable and credible. This goal is achieved by maintaining a Quality System, verified within the obtaining and maintaining of the laboratory accreditation, according to the international standard ISO/IEC 17025:2005.The LDPM is accredited by the Romanian accreditation body, RENAR, member of the European Accreditation, EA and is designed by CNCAN as a notified testing laboratory. Many measurements were performed in collaboration with the Radionuclide Metrology Laboratory (RML) from IFIN-HH, RENAR accredited and CNCAN notified for calibration and for testing in the field of radioactivity measurement. This paper proposes a short presentation of the important aspects in our activity:i.description of equipment, sampling methods, processing and measurement of environmental samples;ii.validation of equipment and methods by participation in international and national proficiency tests;iii.a five year follow chart, containing the results in measurement of samples;iv.a recent application, with a wide impact in Romanian mass media: the credible daily report on the possible influence of Fukushima accident over the Romanian environmental radioactivity.

A Close Look at the Relationship between Multiple Choice Vocabulary Test and Integrative Cloze Test of Lexical Words in Iranian Context

In spite of various definitions provided for it, language proficiency has been always a difficult concept to define and realize. However the commonality of all the definitions for this illusive concept is that language tests should seek to test the learners’ ability to use real-life language. The best type of test to show such ability is considered to be the integrative test and cloze test is in turn regarded to constitute nearly all the factors needed for language use ability. However, the greatest obstacle of cloze tests or in general pragmatic tests is their administrative and scoring constraints for a large number of testees. Discrete-point tests, as the easiest and most common type of tests used for valid national and international proficiency tests, have always been doubtfully questioned as to whether they indicate the learners’ ability to use language in real-life situation, but due to their tangible shortcomings, no absolute answer can be provided. The study aims at shedding light at the idea of the extent to which the discrete items of vocabulary proficiency show the learners’ vocabulary proficiency in the real world of language use. Hence, the study seeks to calculate the correlation between discrete-point and integrative language proficiency tests of vocabulary administered to 21 Iranian freshmen studying English as a Foreign Language.

Quality regulations and accreditation standards for clinical chemistry in Turkey

Objective The purpose of this paper is to review the current status of laboratory quality regulations and accreditation standards in Turkey. Design and method This paper is written based on the current regulations, information collected by available websites and congress proceedings, and personal communications. Results A total of 14 private and one public laboratory have been accredited according to ISO 15189 voluntarily. The total number of the JCI accredited hospitals is 24. One hospital has been accredited by HQS. A few medical laboratories have been accredited according to ISO 17025, whereas a lot of them have ISO 9001 certification from Turkish Accreditation Agency, TURKAK. There are no comprehensive laboratory standards and/or regulations to maintain a mandatory minimum quality of laboratories. External QC is not mandatory and there is no national proficiency testing program. It is a requirement to get a license to open a laboratory. There are residency programs for clinical chemistry and clinical microbiology. The Association of Clinical Biochemists, KBUD, is the youngest society in the field of clinical chemistry and is a leader in quality and accreditation activities. KBUDEK is an external QC program of KBUD. KBUD has organized four national and an international symposiums on quality and accreditation in addition to annual congresses and courses. Conclusion The new standard and regulation should be designed and applied to all laboratories to increase the quality of laboratory service in Turkey. It will be useful if the ISO 15189 standard can be incorporated into the national standards and regulations.

The role of CAP in standardisation of pathology practice, including our laboratory accreditation program, predictive markers (HER2, ER, PR) and pathology report standardisation

Proficiency testing: The College of American Pathologists (CAP) Surveys Program began in 1949, two years after the founding of the College and the first Board initiative to establish a national proficiency testing program. The program was very well received by the US laboratory community and since that time the numbers of laboratories and product offerings have grown steadily. Currently 25000 laboratories are enrolled and test for approximately 1000 analytes. The Surveys Program is primarily peer group based, however, there are considerable educational efforts devoted to establishing best practices to encourage harmonisation in the field. Harmonisation is roughly defined as a narrowing of variability for tests. Proficiency testing in anatomic pathology was initiated in 1990 for gynaecological cytopathology and will soon be rolled out for HER2, ER and PR. Laboratory Accreditation Program (LAP): The CAP is unique in laboratory accreditation services utilising peer review for the vast majority of inspections. This assures that the inspectors are up to date and also ‘in the trenches’ in modern laboratory practice. The requirements of CAP’s LAP program are the most stringent in the industry and are recognised widely as the gold standard. Currently, the CAP certifies over 6500 laboratories in the USA and worldwide. Standardisation of practice and reporting: The first foray of the CAP into standardised reporting came with the development by CAP of the cancer protocols in 1986. These protocols and checklists have become the gold standard in cancer reporting and are now required by the American College of Surgeons (USA) and the American Joint Commission on Cancer (AJCC) for accredited cancer programs. Recently, the CAP has or will publish (in Archives of Pathology and Laboratory Medicine) guidelines for pathology reporting in areas of molecular pathology, surgical pathology and non-gynaecological cytopathology.

Findings of national proficiency test exercise for the determination of trace elements in edible mushroom reference material

This paper presents the results of the proficiency test exercise conducted in Pakistan for the determination of trace elements in mushroom reference material. Thirteen laboratories from different organizations of the country submitted trace elemental data on Al, As, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hg, K, Li, Mg, Mn, Na, P, Pb, Rb Sc, Si, Sm, Sr, Th, Zn. Results for Al, As, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, K, Mg, Mn, Na, Rb Sc, and Zn, in the mushroom material were reported by two or more participating laboratories and could be subjected to statistical evaluation. The original data of these trace elements was subjected to a computer program “Histo Version 2.1” provided by IAEA. The four outlier tests, i.e., Dixon, Grubbs, skewness and kurtosis were applied to the data sets. Consensus (overall) mean values, absolute standard deviation, relative standard deviation, standard error, median and range of values for these elements have been reported at a significance level of 0.05.

Diagnostic Sweat Testing: The Cystic Fibrosis Foundation Guidelines

he Cystic Fibrosis Foundation (CFF) accredits cystic fibrosis (CF) centers, located in teaching and community hospitals nationwide, which provide comprehensive diagnosis and treatment for people with CF. The CF centers are evaluated by the CFF Center Committee according to specific criteria covering the areas of clinical care, teaching, and research. here are specific requirements for sweat testing, and adherence to them is required for accreditation. In 2006, the CFF Center ommittee distributed a sweat testing guidelines memorandum to the CF center directors. Although the guidelines are based n the Clinical Laboratory Standards Institute (CLSI), formerly National Committee for Clinical Laboratory Standards, sweat esting document C34-A2 and the College of American Pathologists (CAP) Laboratory Accreditation Program Inspection hecklist items for sweat testing, they are more prescriptive for uniformity and are focused on diagnostic rather than screening weat tests. The guidelines are applicable to patients of all ages undergoing sweat chloride testing. Adherence to the guidelines is mandatory for CFF centers; however, the requirements are appropriate and adaptable for any acility performing diagnostic testing for CF. Although it may be ideal for sweat testing to be centralized at CF centers, in practice his does not occur. According to enrollment in a national proficiency testing program for sweat analysis, more than 600 laboratories erformed sweat testing in 2006. With widespread implementation of newborn screening programs for CF, the reliance on a ell-performed and well-interpreted sweat test is critical to the success of accurately diagnosing CF. Sweat chloride testing should be erformed on all infants with a positive newborn screen even in cases in which two CF-causing mutations have been identified. The following represent the 2006 CFF sweat testing guidelines, along with commentary discussing the specific guidelines.

Language Learner Strategy Use and Test Performance of Chinese Learners of English

This article examines language learner strategy use reported by 121 Chinese learners of English through a questionnaire and the relationships between their strategy use and language performance on a national English proficiency test: College English Test–Band 4. Results showed that this group of learners reported using more metacognitive strategies than cognitive strategies in general. One subscale of cognitive strategies—inferencing—was reportedly used most frequently. Memory and retrieval strategies as a scale of cognitive strategies were the only significant predictor of the College English Test–Band 4, accounting for 8.6% of the variance in the test. A further examination of the relationship between the subscales of strategy use and the CET showed inferency and practicing naturalistically were the best predictors of the CET. The complex relationships between learner strategy use and their test performance are discussed with suggestions for further research.

Editorial Comment

No AccessJournal of UrologyAdult urology1 Jun 2006Editorial Comment Dolores J. Lamb and Mark Sigman Dolores J. LambDolores J. Lamb Scott Department of Urology, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas More articles by this author and Mark SigmanMark Sigman Department of Urology, Brown University School of Medicine, Providence, Rhode Island More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(06)00655-0AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Editorial Comment." The Journal of Urology, 175(6), p. 2227 References 1 : The spermatozoa count. N Engl J Med1929; 200:: 981. Google Scholar 2 : Results of the American Association of Bioanalysts national proficiency testing programme in andrology. Hum Reprod2000; 15:: 680. Google Scholar 3 : Relation between indices of semen analysis and pregnancy rate in infertile couples. Fertil Steril1977; 28:: 1314. Google Scholar © 2006 by American Urological AssociationFiguresReferencesRelatedDetails Volume 175Issue 6June 2006Page: 2227 Advertisement Copyright & Permissions© 2006 by American Urological AssociationMetricsAuthor Information Dolores J. Lamb Scott Department of Urology, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas More articles by this author Mark Sigman Department of Urology, Brown University School of Medicine, Providence, Rhode Island More articles by this author Expand All Advertisement PDF downloadLoading ...

Reference Impact Specimens Made from Low Carbon Steel: Report on Production and Use

Abstract This paper describes a method of producing reference specimens from low carbon steel and reports the results of a national proficiency testing by 45 laboratories. The reference impact specimens of low carbon steel are much cheaper than the traditional ones, and the proficiency testing proved that the specimens are valid for finding out the problems of impact machines. Furthermore, the data showed that an impact machine would represent the similar relative bias at a different energy level of reference specimen, so it is sufficient to use reference specimens with one absorbed energy level to verify impact machines annually.

A Comparison of Fibre Counting Across Three European National Proficiency Testing Schemes

Proficiency testing (PT) schemes seek to improve and maintain consistency in asbestos fibre counting by circulating mounted samples to laboratories, which return counts for comparison with consensus reference values. This study compares the level of these consensus values in three (Spanish, Belgian and UK) national PT schemes. It also assesses the effect of the imminent change in the European standard rules for counting asbestos fibres, to the new rules from the World Health Organisation (WHO), which will include more fibres. Forty samples from the three schemes were circulated to six laboratories, two in each national scheme. The UK and Spanish laboratories counted using both the ERM and the WHO method. Belgian laboratories already use the WHO method, and they counted only by this method. Densities from counts in this sample exchange served as a common basis against which we compared the national reference values (R). This produced a geometric overall mean ratio of R to exchange mean density of 0.94 for the UK scheme, 1.01 for the Spanish and 0.97 for the Belgian scheme, and thus indicated remarkably similar levels. Nevertheless, non-trivial systematic inter-laboratory differences confirmed the need for regular PT and international inter-laboratory comparisons. Examination of previous data from the national PT schemes and from an international scheme (AFRICA) provided further comparisons for the same laboratories (either comparing the laboratory's data with R values or making direct comparisons between laboratories) that are consistent with those from this special exchange. The change in fibre counting rule (to include fibres apparently touching particles with diameter >3 microm) produced mean increases in reported densities that ranged among samples from 0 to 70% (highest individual estimate 170%); the effect was broadly similar for the three schemes. The laboratories gave mostly similar estimates of percentage increase; however, one laboratory occasionally produced high estimates indicating a possible need for training for using the new method.

Impact of a common CV evaluation scheme on overall laboratory performance: 8-year experience of a large national proficiency testing program in Japan

In proficiency testing (PT), it is difficult to set rational criteria for determining target values and allowable limits. In Japan, the largest national PT program has for the past 8 years used an evaluation scheme based on a "common coefficient of variation" (cCV) to overcome this difficulty. The cCV, the average within-method variation, is derived by one-way analysis of variance from data of peer groups after excluding those with large variations. A unit interval used for grading participants is obtained by multiplying the cCV by the peer-group mean which is computed using an iterative method featuring repeated removal of a large portion of the tails of the distribution and reinflation of the standard deviation (SD) to compensate for the trimming. The evaluation scheme gives a relatively better grade to those participants in peer groups with small CVs, compared to use of individual peer-group CVs. The scheme has expedited the transition to more reproducible methods, resulting in a notable overall improvement in laboratory performance. The cCV evaluation scheme is uniformly applicable to any analyte measured quantitatively. The iterative method, an integral part of the scheme, effectively precludes bias in the evaluation.

ISO 15189: A WORLDWIDE STANDARD FOR MEDICAL LABORATORIES

From the University of Wisconsin Medical School, Department of Pathology and Laboratory Medicine, Madison, WI. Dr. Libeer is head of the department of clinical biology at the National Institute of Public Health in Brussels, Belgium. His department is in charge of licensing medical laboratories in Belgium and is in charge of the organization of the national proficiency testing schemes. Dr. Libeer has a particular interest in laboratory quality management and, along with Dr. Henk Goldschmidt, organizes the Antwerp “Quality in the Spotlight” conferences. In ISO TC212 he represents his national standardization body. He is also president of EQALM (the European umbrella organization of PT providers in clinical laboratories). Reprints: Sharon L. Ehrmeyer, PhD, University of Wisconsin Medical School, Department of Pathology and Laboratory Medicine, Medical Science Center, 1300 University Avenue Madison, WI 53706 (e-mail: [email protected]).

External quality assessment in gynaecological cytology: The Trent Region experience. The Trent Regional Gynaecological Pathology Quality Assurance Group for the National Health Service Cervical Screening Programme.

A Department of Health Executive Letter stated in 1998 that the principal function of external quality assessment (EQA) is educational. Subsequently, in England, it has no longer been acceptable to assess performance in gynaecological cytology by proficiency testing. This paper describes the EQA scheme in gynaecological cytology that has been run by the Trent Regional Gynaecological Pathology Quality Assurance Group for the NHS Cervical Screening Programme (NHSCSP) since 1998. It conforms as closely as possible to the recommendations published by the Department of Health Working Group on Histopathology EQA Accreditation, and replaced the national proficiency testing protocol. The educational value of the scheme is derived predominantly from a numerical score which provides confidential and quantitative feedback to all participants. Personal performance monitoring occurs as a secondary function. For primary screeners and checkers, this is based purely on the distinction between negative, inadequate and abnormal smears. For pathologists, personal performance monitoring also includes grading of abnormalities. The EQA has been designed so that all professional groups participate in a manner that closely mimics normal practice. Only slides that have achieved an 80% consensus amongst participants are used in the EQA. Substandard performance has been defined as those participants with scores falling below the 2.5%ile. The paper describes the EQA in detail and illustrates its use by means of the second round results. The EQA protocol developed within Trent and described in this paper has contributed to proposals contained in the current national EQA in gynaecological cytology for the NHSCSP. In particular this paper highlights the effectiveness of the scoring system contained within the Trent and National EQA protocols.

Comparison of standard reading and computer aided detection (CAD) on a national proficiency test of screening mammography

Objective: To evaluate the role of computer aided detection (CAD) in improving the interpretation of screening mammograms Material and methods: Ten radiologists underwent a proficiency test of screening mammography first by conventional reading and then with the help of CAD. Radiologists were blinded to test results for the whole study duration. Results of conventional and CAD reading were compared in terms of sensitivity and recall rate. Double reading was simulated combining conventional readings of four expert radiologists and compared with CAD reading. Results: Considering all ten readings, cancer was identified in 146 or 153 of 170 cases (85.8 vs. 90.0%; χ 2=0.99, df=1, P=0.31) and recalls were 106 or 152 of 1330 cases (7.9 vs. 11.4%; χ 2=8.69, df=1, P=0.003) at conventional or CAD reading, respectively. CAD reading was essentially the same (sensitivity 97.0 vs. 96.0%; χ 2=7.1, df=1, P=0.93; recall rate 10.7 vs. 10.6%; χ 2=1.5, df=1, P=0.96) as compared with simulated conventional double reading. Conclusion: CAD reading seems to improve the sensitivity of conventional reading while reducing specificity, both effects being of limited size. CAD reading had almost the same performance of simulated conventional double reading, suggesting a possible use of CAD which needs to be confirmed by further studies inclusive of cost-effective analysis.