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Uppsala, Sweden

Eklund C.,Lund University | Eklund C.,Karolinska Institute and Hospital | Forslund O.,Lund University | Wallin K.-L.,Equalis AB | And 3 more authors.
Journal of Clinical Microbiology | Year: 2012

Accurate and internationally comparable human papillomavirus (HPV) DNA genotyping is essential both for evaluation of HPV vaccines and for effective monitoring and implementation of vaccination programs. The World Health Organization (WHO) HPV Laboratory Network (LabNet) regularly issues international proficiency studies. The 2010 HPV genotyping proficiency panel for HPV vaccinology contained 43 coded samples composed of purified plasmids of 16 HPV types (HPV types 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68a and 68b) and 3 coded extraction controls. Proficient typing was defined as detection in both single and multiple infections of 50 international units (IU) of HPV type 16 (HPV-16) and HPV-18 DNA and 500 genome equivalents (GE) for the other 14 HPV types. Ninety-eight laboratories worldwide submitted a total of 132 data sets. Twenty-four different HPV genotyping assay methods were used, with Linear Array being the most commonly used. Other major assays used were a line blot assay (Inno-LiPa), CLART, type-specific real-time PCR, PCR Luminex, and different microarray assays. Altogether, 72 data sets were proficient for detection of more than 1 type, and only 26 data sets proficiently detected all 16 HPV types. The major oncogenic HPV types, 16 and 18, were proficiently detected in 95.0% (114/120) and 87.0% (94/108) of data sets, respectively. Forty-six data sets reported multiple false-positive results and were considered nonproficient. A trend toward increased sensitivity of assays was seen for the 41 laboratories that participated in both 2008 and 2010. In conclusion, continued global proficiency studies will be required for establishing comparable and reliable HPV genotyping services for vaccinology worldwide. Copyright © 2012, American Society for Microbiology. All Rights Reserved. Source

Eklund C.,Lund University | Eklund C.,Karolinska Institute and Hospital | Forslund O.,Lund University | Wallin K.-L.,Equalis AB | And 2 more authors.
Journal of Clinical Microbiology | Year: 2014

Accurate and internationally comparable human papillomavirus (HPV) DNA genotyping is essential for HPV vaccine research and for HPV surveillance. The HPV Laboratory Network (LabNet) has designed international proficiency studies that can be issued regularly and in a reproducible manner. The 2011 HPV genotyping proficiency panel contained 43 coded samples composed of purified plasmids of 16 HPV types (HPV6,-11,-16,-18,-31,-33,-35,-39,-45,-51,-52,-56,-58,- 59,-66,-68a, and-68b) and 3 extraction controls. Tests that detected 50 IU of HPV16 and HPV18 and 500 genome equivalents for the other 14 HPV types in both single and multiple infections were considered proficient. Ninety-six laboratories worldwide submitted 134 data sets. Twenty-five different HPV genotyping assay methods were used, including the Linear Array, line blot/INNO-LiPA, Papillo-Check, and PCR Luminex assays. The major oncogenic HPV types, HPV16 and HPV18, were proficiently detected in 97.0% (113/ 116) and 87.0% (103/118) of the data sets, respectively. In 2011, 51 data sets (39%) were 100% proficient for the detection of at least one HPV type, and 37 data sets (28%) were proficient for all 16 HPV types; this was an improvement over the panel results from the 2008 and 2010 studies, when>25 data sets (23% and 19% for 2008 and 2010, respectively) were fully proficient. The improvement was also evident for the 54 laboratories that had also participated in the previous proficiency studies. In conclusion, a continuing global proficiency program has documented worldwide improvement in the comparability and reliability of HPV genotyping assay performances. Copyright © 2014, American Society for Microbiology. All Rights Reserved. Source

Background: To explore to what extent measurement error can explain the variation of mean patient HbA1c between clinics. Methods: For each year 2005-2010 data from 5380-6985 children, age < 18 years, in 35-43 Swedish pediatric clinics was analyzed. Each year 13,000-19,000 HbA1c analyses were evaluated. Year mean HbA1c for each patient was calculated for HbA1c values when insulin dose was ≥ 0.5 U/kg. In Sweden HbA1c values were during the study period standardized to the Mono S level, HbA1c(Mono S)%, but are given also in the international unit HbA1c(IFCC), mmol/mol. Performance of locally measured HbA 1c is monitored by Equalis through monthly external quality assessment (EQA) schemes. Results: The yearly mean bias term for each clinic varied from -0.54 to 0.41 HbA1c(Mono S)%. The bias between clinic HbA1c and target value improved during the 6 years and the mean bias was for 79%-88% of clinics within the recommended level ± 0.14 HbA 1c% the last 2 years. Inter-clinic mean HbA1c had a wide interquartile range, 0.30-0.43 HbA1c(Mono S)% [3.2-4.5 HbA 1c(IFCC) mmol/mol]. Conclusions: Regular participation in EQA schemes is necessary when comparing HbA1c values. The measurement error decreased during the 6-year period and explained from 28% to < 10% of the inter-clinic variation in year mean clinic HbA1c. Source

Tragardh E.,Skane University Hospital | Ljungberg M.,Lund University | Edenbrandt L.,Skane University Hospital | Orndahl E.,Equalis AB | And 6 more authors.
EJNMMI Physics | Year: 2015

Background: Myocardial perfusion scintigraphy (MPS) is a clinically useful noninvasive imaging modality for diagnosing patients with suspected coronary artery disease. By utilizing gated MPS, the end diastolic volume (EDV) and end systolic volume (ESV) can be measured and the ejection fraction (EF) calculated, which gives incremental prognostic value compared with assessment of perfusion only. The aim of this study was to evaluate the inter-departmental variability of EF, ESV, and EDV during gated MPS in Sweden. Methods: Seventeen departments were included in the study. The SIMIND Monte Carlo (MC) program together with the XCAT phantom was used to simulate three patient cases with different EDV, ESV, and EF. Individual simulations were performed for each department, corresponding to their specific method of performing MPS. Images were then sent to each department and were evaluated according to clinical routine. EDV, ESV, and EF were reported back. Results: There was a large underestimation of EDV and ESV for all three cases. Mean underestimation for EDV varied between 26% and 52% and for ESV between 15% and 60%. EF was more accurately measured, but mean bias still varied between an underestimation of 24% to an overestimation of 14%. In general, the intra-departmental variability for EDV, ESV, and EF was small, whereas inter-departmental variability was larger. Conclusions: Left ventricular volumes were generally underestimated, whereas EF was more accurately estimated. There was, however, large inter-departmental variability. © 2015, Trägårdh et al.; licensee Springer. Source

Kristoffersen A.-H.,University of Bergen | Thue G.,University of Bergen | Ajzner E.,Central Laboratory | Claes N.,Hasselt University | And 16 more authors.
Thrombosis Research | Year: 2012

Introduction: Standardisation of treatment with vitamin K antagonists (VKAs) is still an issue after 60 years of use. The study aimed to explore aspects of VKA monitoring in primary and secondary care. Methods: Two case histories were distributed to physicians in 13 countries. Case history A focused on a patient with atrial fibrillation on stable anticoagulation (latest INR 2.3). Physicians were asked about frequency of INR measurement, when to change the VKA dose, and the patient's annual risk of ischemic stroke and bleeding. Case history B focused on a patient with an unexpected INR of 4.8, asking for the patient's 48-hour bleeding risk, the immediate dose reduction and time until a repeat INR. Results: Altogether, 3016 physicians responded (response rate 8 - 38%), of which 82% were from primary care and 18% from secondary care. Answers varied substantially within and between countries regardless of level of care and VKA used. Median number of weeks between INR measurements was 4 - 6 weeks. Median threshold INR for increasing or decreasing the VKA dose was 1.9 and 3.1, respectively. Risk of ischemic stroke and bleeding were overestimated 2 - 3 times. In case history B, the median dose reduction the two first days was 75% for GPs and 55% for specialists, irrespective of estimates of bleeding risk; with one week to a repeat INR. Conclusion: Variation in VKA monitoring is substantial implying clinical consequences. Guidelines seem either unknown or may be considered impracticable. Further efforts towards standardisation of VKA management are needed. © 2012 Elsevier Ltd. Source

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