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Siebert, Uwe

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Siebert

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Uwe

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Siebert, Uwe

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Now showing 1 - 10 of 18
  • Publication

    Prostate-Specific Antigen Testing in Tyrol, Austria: Prostate Cancer Mortality Reduction Was Supported by an Update with Mortality Data up to 2008

    (SP Birkhäuser Verlag Basel, 2012) Oberaigner, Willi; Siebert, Uwe; Horninger, Wolfgang; Klocker, Helmut; Bektic, Jasmin; Schäfer, Georg; Frauscher, Ferdinand; Schennach, Harald; Bartsch, Georg

    Objectives: The objective of this study was to update an in-depth analysis of the time trend for prostate cancer (PCA) mortality in the population of Tyrol by 5 years, namely to 2008. In Tyrol, prostate-specific antigen (PSA) tests were introduced in 1988/89; more than three-quarters of all men in the age group 45–74 had at least one PSA test in the past decade. Methods: We applied the same model as in a previous publication, i.e., an age-period-cohort model using Poisson regression, to the mortality data covering more than three decades from 1970 to 2008. Results: For Tyrol from 2004 to 2008 in the age group 60+ period terms show a significant reduction in prostate cancer mortality with a risk ratio of 0.70 (95% confidence interval 0.57, 0.87) for Tyrol, and for Austria excluding Tyrol a moderate reduction with a risk ratio of 0.92 (95% confidence interval 0.87, 0.97), each compared to the mortality rate in the period 1989–1993. Conclusions: This update strengthens our previously published results, namely that PSA testing offered to a population at no charge can reduce prostate cancer mortality. The extent of mortality reduction is in line with that reported in the other recent publications. However, our data do not permit us to fully assess the harms associated with PCA screening, and no recommendation for PSA screening can be made without a careful evaluation of overdiagnosis and overtreatment.

  • Publication

    Mapping the EQ-5D index by UPDRS and PDQ-8 in patients with Parkinson’s disease

    (BioMed Central, 2013) Dams, Judith; Klotsche, Jens; Bornschein, Bernhard; Reese, Jens P; Balzer-Geldsetzer, Monika; Winter, Yaroslav; Schrag, Anette; Siderowf, Andrew; Oertel, Wolfgang H; Deuschl, Günther; Siebert, Uwe; Dodel, Richard

    Background: Clinical studies employ the Unified Parkinson’s Disease Rating Scale (UPDRS) to measure the severity of Parkinson’s disease. Evaluations often fail to consider the health-related quality of life (HrQoL) or apply disease-specific instruments. Health-economic studies normally use estimates of utilities to calculate quality-adjusted life years. We aimed to develop an estimation algorithm for EuroQol- 5 dimensions (EQ-5D)-based utilities from the clinical UPDRS or disease-specific HrQoL data in the absence of original utilities estimates. Methods: Linear and fractional polynomial regression analyses were performed with data from a study of Parkinson’s disease patients (n=138) to predict the EQ-5D index values from UPDRS and Parkinson’s disease questionnaire eight dimensions (PDQ-8) data. German and European weights were used to calculate the EQ-5D index. The models were compared by R2, the root mean square error (RMS), the Bayesian information criterion, and Pregibon’s link test. Three independent data sets validated the models. Results: The regression analyses resulted in a single best prediction model (R2: 0.713 and 0.684, RMS: 0.139 and 13.78 for indices with German and European weights, respectively) consisting of UPDRS subscores II, III, IVa-c as predictors. When the PDQ-8 items were utilised as independent variables, the model resulted in an R2 of 0.60 and 0.67. The independent data confirmed the prediction models. Conclusion: The best results were obtained from a model consisting of UPDRS subscores II, III, IVa-c. Although a good model fit was observed, primary EQ-5D data are always preferable. Further validation of the prediction algorithm within large, independent studies is necessary prior to its generalised use.

  • Publication

    Introduction of organised mammography screening in tyrol: results of a one-year pilot phase

    (BioMed Central, 2011) Oberaigner, Willi; Buchberger, Wolfgang; Frede, Thomas; Daniaux, Martin; Knapp, Rudolf; Marth, Christian; Siebert, Uwe

    Background: Efficiency and efficacy of organised mammography screening programs have been proven in large randomised trials. But every local implementation of mammography screening has to check whether the well established quality standards are met. Therefore it was the aim of this study to analyse the most common quality indices after introducing organised mammography screening in Tyrol, Austria, in a smooth transition from the existing system of opportunistic screening. Methods: In June 2007, the system of opportunistic mammography screening in Tyrol was changed to an organised system by introducing a personal invitation system, a training program, a quality assurance program and by setting up a screening database. All procedures are noted in a written protocol. Most EU recommendations for organised mammography screening were followed, except double reading. All women living in Tyrol and covered by social insurance are now invited for a mammography, in age group 40-59 annually and in age group 60-69 biannually. Screening mammography is offered mainly by radiologists in private practice. We report on the results of the first year of piloting organised mammography screening in two counties in Tyrol. Results: 56,432 women were invited. Estimated participation rate was 34.5% at one year of follow-up (and 55.5% at the second year of follow-up); 3.4% of screened women were recalled for further assessment or intermediate screening within six months. Per 1000 mammograms nine biopsies were performed and four breast cancer cases detected (N = 68). Of invasive breast cancer cases 34.4% were ≤ 10 mm in size and 65.6% were node-negative. In total, six interval cancer cases were detected during one year of follow-up; this is 19% of the background incidence rate. Conclusions: In the Tyrolean breast cancer screening program, a smooth transition from a spontaneous to an organised mammography screening system was achieved in a short time and with minimal additional resources. One year after introduction of the screening program, most of the quality indicators recommended by the European guidelines had been reached. However, it will be necessary to introduce double reading, to change the rule for BI-RADS 3, and to concentrate on actions toward improving the participation rate.

  • Publication

    COMMUNICATING THE PARAMETER UNCERTAINTY IN THE IQWIG EFFICIENCY FRONTIER TO DECISION-MAKERS

    (John Wiley & Sons, Ltd, 2014) Stollenwerk, Björn; Lhachimi, Stefan K; Briggs, Andrew; Fenwick, Elisabeth; Caro, Jaime J; Siebert, Uwe; Danner, Marion; Gerber-Grote, Andreas

    The Institute for Quality and Efficiency in Health Care (IQWiG) developed—in a consultation process with an international expert panel—the efficiency frontier (EF) approach to satisfy a range of legal requirements for economic evaluation in Germany's statutory health insurance system. The EF approach is distinctly different from other health economic approaches. Here, we evaluate established tools for assessing and communicating parameter uncertainty in terms of their applicability to the EF approach. Among these are tools that perform the following: (i) graphically display overall uncertainty within the IQWiG EF (scatter plots, confidence bands, and contour plots) and (ii) communicate the uncertainty around the reimbursable price. We found that, within the EF approach, most established plots were not always easy to interpret. Hence, we propose the use of price reimbursement acceptability curves—a modification of the well-known cost-effectiveness acceptability curves. Furthermore, it emerges that the net monetary benefit allows an intuitive interpretation of parameter uncertainty within the EF approach. This research closes a gap for handling uncertainty in the economic evaluation approach of the IQWiG methods when using the EF. However, the precise consequences of uncertainty when determining prices are yet to be defined. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd.

  • Publication

    Recall Responses to Tetanus and Diphtheria Vaccination Are Frequently Insufficient in Elderly Persons

    (Public Library of Science, 2013) Weinberger, Birgit; Schirmer, Michael; Matteucci Gothe, Raffaella; Siebert, Uwe; Fuchs, Dietmar; Grubeck-Loebenstein, Beatrix

    Demographic changes and a more active life-style in older age have contributed to an increasing public awareness of the need for lifelong vaccination. Currently many older persons have been vaccinated against selected pathogens during childhood but lack regular booster immunizations. The impact of regular vaccinations when started late in life was analyzed in an open, explorative trial by evaluating the immune response against tetanus and diphtheria in healthy older individuals. 252 persons aged above 60 years received a booster vaccination against tetanus, diphtheria, pertussis and polio and a subcohort (n=87) was recruited to receive a second booster vaccination against tetanus, diphtheria and pertussis 5 years later. The percentage of unprotected individuals at the time of enrollment differed substantially for tetanus (12%) and diphtheria (65%). Despite protective antibody concentrations 4 weeks after the first vaccination in almost all vaccinees, antibodies had again dropped below protective levels in 10% (tetanus) and 45% (diphtheria) of the cohort after 5 years. Protection was restored in almost all vaccinees after the second vaccination. No correlation between tetanus- and diphtheria-specific responses was observed, and antibody concentrations were not associated with age-related changes in the T cell repertoire, inflammatory parameters, or CMV-seropositivity suggesting that there was no general biological “non-responder type.” Post-vaccination antibody concentrations depended on pre-existing plasma cells and B cell memory as indicated by a strong positive relationship between post-vaccination antibodies and pre-vaccination antibodies as well as antibody-secreting cells. In contrast, antigen-specific T cell responses were not or only weakly associated with antibody concentrations. In conclusion, our findings demonstrate that single shot vaccinations against tetanus and/or diphtheria do not lead to long-lasting immunity in many elderly persons despite administration at relatively short intervals. Sufficient antigen-specific B cell memory B generated by adequate priming and consecutive booster vaccinations and/or exposure is a prerequisite for long-term protection. Trial Registration EU Clinical Trials Register (EU-CTR); EudraCT number 2009-011742-26; www.clinicaltrialsregister.eu/ctr-search/trial/2009-011742-26/AT

  • Publication

    Comparing the Clinical Effectiveness of Different New-Born Hearing Screening Strategies. A Decision Analysis

    (BioMed Central, 2005) Grill, Eva; Hessel, Franz; Siebert, Uwe; Schnell-Inderst, Petra; Kunze, Silke; Nickisch, Andreas; Wasem, Jürgen

    Background: Children with congenital hearing impairment benefit from early detection and treatment. At present, no model exists which explicitly quantifies the effectiveness of universal newborn hearing screening (UNHS) versus other programme alternatives in terms of early diagnosis. It has yet to be considered whether early diagnosis (within the first few months) of hearing impairment is of importance with regard to the further development of the child compared with effects resulting from a later diagnosis. The objective was to systematically compare two screening strategies for the early detection of new-born hearing disorders, UNHS and risk factor screening, with no systematic screening regarding their influence on early diagnosis. Methods / Design: Clinical effectiveness analysis using a Markov Model. Data Sources: Systematic literature review, empirical data survey, and expert opinion. Target Population: All newborn babies. Time scale: 6, 12 and 120 months. Perspective: Health care system. Compared Strategies: UNHS, Risk factor screening (RS), no systematic screening (NS). Outcome Measures: Quality weighted detected child months (QCM).Results UNHS detected 644 QCM up until the age of 6 months (72,2%). RS detected 393 child months (44,1%) and no systematic screening 152 child months (17,0%). UNHS detected 74,3% and 86,7% weighted child months at 12 and 120 months, RS 48,4% and 73,3%, NS 23,7% and 60,6%. At the age of 6 months UNHS identified approximately 75% of all children born with hearing impairment, RS 50% and NS 25%. At the time of screening UNHS marked 10% of screened healthy children for further testing (false positives), RS 2%. UNHS demonstrated higher effectiveness even under a wide range of relevant parameters. The model was insensitive to test parameters within the assumed range but results varied along the prevalence of hearing impairment. Conclusion: We have shown that UNHS is able to detect hearing impairment at an earlier age and more accurately than selective RS. Further research should be carried out to establish the effects of hearing loss on the quality of life of an individual, its influence on school performance and career achievement and the differences made by early fitting of a hearing aid on these factors.

  • Publication

    Antiviral Combination Therapy with Interferon/Peginterferon Plus Ribavirin for Patients with Chronic Hepatitis C in Germany: A Health Technology Assessment Commissioned by the German Agency for Health Technology Assessment

    (German Medical Science, 2003) Sroczynski, Gaby; Siebert, Uwe; German Hepatitis C Model (GEHMO) Group; HTA Expert Panel on Hepatitis C

    Objective: The purpose of this health technology assessment (HTA), commissioned by the German Agency for HTA at the German Federal Ministry of Health and Social Security, was to systematically review the evidence on effectiveness and cost-effectiveness of antiviral treatment (AVT) for initial chronic hepatitis C (CHC) and to apply these data in the context of the German health care system. Methods: A systematic literature search was conducted to identify randomised controlled trials (RCTs), meta-analyses, and HTAs that evaluated initial AVT for CHC. A modified version of the German Hepatitis C Model (GEHMO) -- a decision-analytic Markov model -- was used to determine long-term morbidity, life expectancy, quality of life, costs and cost-effectiveness of different treatment strategies. Model parameters were derived from German databases, international RCTs, and a Cochrane Review. Results: Overall, 9 RCTs, 2 HTA reports, 1 Cochrane review, and 2 meta-analyses examining medical effectiveness of antiviral combination therapy, as well as 7 economic evaluations, met the inclusion criteria. These studies indicate that combination therapy with peginterferon plus ribavirin produced the highest sustained virological response rates (54-61%), followed by interferon plus ribavirin with 38-54%, and interferon monotherapy with 11-21%. Based on international cost-effectiveness studies, interferon plus ribavirin is cost-effective compared to interferon monotherapy. No published articles were available regarding cost-effectiveness of peginterferon plus ribavirin. In our decision analysis, these findings were confirmed and the discounted incremental cost-effectiveness ratio for peginterferon plus ribavirin was € 9,800 per quality-adjusted life-year gained compared to interferon monotherapy (as the next best non-dominated strategy). Sensitivity analyses showed robust results across a wide range of model parameters. Conclusions: This HTA suggests that initial combination therapy prolongs life, improves quality of life, and is cost-effective in patients with CHC. Combination of peginterferon and ribavirin is the most effective and efficient treatment strategy among the examined options.

  • Publication

    Breast Cancer Incidence and Mortality in Tyrol/Austria after Fifteen Years of Opportunistic Mammography Screening

    (BioMed Central, 2010) Oberaigner, Willi; Buchberger, Wolfgang; Frede, Thomas; Knapp, Rudolf; Marth, Christian; Siebert, Uwe

    Background: The aim of this study was to analyse breast cancer incidence and mortality in Tyrol from 1970 to 2006, namely after performing more than a decade of opportunistic mammography screening and just before piloting an organised screening programme. Our investigation was conducted on a population level. Methods: To study time trends in breast cancer incidence and mortality, we applied the age-period-cohort model by Poisson regression to the official mortality data covering more than three decades from 1970 to 2006 and to the incidence data ranging from 1988 to 2006. In addition, for incidence data we analysed data on breast cancer staging and compared these with EU guidelines. Results: For the analysis of time trend in breast cancer mortality in age groups 40-79, an age-period-cohort model fits well and shows for years 2002-2006 a statistically significant reduction of 26% (95% CI 13%-36%) in breast cancer mortality as compared to 1992-1996. We see only slight non-significant increases in breast cancer incidence. For the past five years, incidence data show a 10% proportion of in situ cases, and of 50% for cases in stages II+. Conclusions: The opportunistic breast cancer screening programme in Tyrol has only in part exploited the mortality reduction known for organised screening programmes. There seems to be potential for further improvement, and we recommend that an organised screening programme and a detailed screening database be introduced to collect all information needed to analyse the quality indicators suggested by the EU guidelines.

  • Publication

    Economic Evaluation of Newborn Hearing Screening: Modelling Costs and Outcomes

    (German Medical Science, 2003) Hessel, Franz; Grill, Eva; Schnell-Inderst, Petra; Siebert, Uwe; Kunze, Silke; Nickisch, Andreas; von Voß, Hubertus; Wasem, Jürgen

    Objectives: The prevalence of newborn hearing disorders is 1-3 per 1,000. Crucial for later outcome are correct diagnosis and effective treatment as soon as possible. With BERA and TEOAE low-risk techniques for early detection are available. Universal screening is recommended but not realised in most European health care systems. Aim of the study was to examine the scientific evidence of newborn hearing screening and a comparison of medical outcome and costs of different programmes, differentiated by type of strategy (risk screening, universal screening, no systematical screening). Methods: In an interdisciplinary health technology assessment project all studies on newborn hearing screening detected in a standardized comprehensive literature search were identified and data on medical outcome, costs, and cost-effectiveness extracted. A Markov model was designed to calculate cost-effectiveness ratios. Results: Economic data were extracted from 20 relevant publications out of 39 publications found. In the model total costs for screening of 100,000 newborns with a time horizon of ten years were calculated: 2.0 Mio.€ for universal screening (U), 1.0 Mio.€ for risk screening (R), and 0.6 Mio.€ for no screening (N). The costs per child detected: 13,395€ (U) respectively 6,715€ (R), and 4,125€ (N). At 6 months of life the following percentages of cases are detected: U 72%, R 43%, N 13%. Conclusions: A remarkable small number of economic publications mainly of low methodological quality was found. In our own model we found reasonable cost-effectiveness ratios also for universal screening. Considering the outcome advantages of higher numbers of detected cases a universal newborn hearing screening is recommended.

  • Publication

    HCV-Related Burden of Disease in Europe: A Systematic Assessment of Incidence, Prevalence, Morbidity, and Mortality

    (BioMed Central, 2009) Mühlberger, Nikolai; Schwarzer, Ruth; Lettmeier, Beate; Sroczynski, Gaby; Zeuzem, Stefan; Siebert, Uwe

    Background: Hepatitis C virus (HCV) is a leading cause of chronic liver disease, end-stage cirrhosis, and liver cancer, but little is known about the burden of disease caused by the virus. We summarised burden of disease data presently available for Europe, compared the data to current expert estimates, and identified areas in which better data are needed. Methods: Literature and international health databases were systematically searched for HCV-specific burden of disease data, including incidence, prevalence, mortality, disability-adjusted life-years (DALYs), and liver transplantation. Data were collected for the WHO European region with emphasis on 22 countries. If HCV-specific data were unavailable, these were calculated via HCV-attributable fractions. Results: HCV-specific burden of disease data for Europe are scarce. Incidence data provided by national surveillance are not fully comparable and need to be standardised. HCV prevalence data are often inconclusive. According to available data, an estimated 7.3–8.8 million people (1.1–1.3%) are infected in our 22 focus countries. HCV-specific mortality, DALY, and transplantation data are unavailable. Estimations via HCV-attributable fractions indicate that HCV caused more than 86000 deaths and 1.2 million DALYs in the WHO European region in 2002. Most of the DALYs (95%) were accumulated by patients in preventable disease stages. About one-quarter of the liver transplants performed in 25 European countries in 2004 were attributable to HCV. Conclusion: Our results indicate that hepatitis C is a major health problem and highlight the importance of timely antiviral treatment. However, data on the burden of disease of hepatitis C in Europe are scarce, outdated or inconclusive, which indicates that hepatitis C is still a neglected disease in many countries. What is needed are public awareness, co-ordinated action plans, and better data. European physicians should be aware that many infections are still undetected, provide timely testing and antiviral treatment, and avoid iatrogenic transmission.