Final Measurement of the

This Letter reports one of the most precise measurements to date of the antineutrino spectrum from a purely ^{235}U-fueled reactor, made with the final dataset from the PROSPECT-I detector at the High Flux Isotope Reactor. By extracting information from previously unused detector segments, this analysis effectively doubles the statistics of the previous PROSPECT measurement. The reconstructed energy spectrum is unfolded into antineutrino energy and compared with both the Huber-Mueller model and a spectrum from a commercial reactor burning multiple fuel isotopes. A local excess over the model is observed in the 5-7 MeV energy region. Comparison of the PROSPECT results with those from commercial reactors provides new constraints on the origin of this excess, disfavoring at 2.0 and 3.7 standard deviations the hypotheses that antineutrinos from ^{235}U are solely responsible and noncontributors to the excess observed at commercial reactors, respectively.

Joint Determination of Reactor Antineutrino Spectra from

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Joint Measurement of the

The PROSPECT and STEREO collaborations present a combined measurement of the pure ^{235}U antineutrino spectrum, without site specific corrections or detector-dependent effects. The spectral measurements of the two highest precision experiments at research reactors are found to be compatible with χ^{2}/ndf=24.1/21, allowing a joint unfolding of the prompt energy measurements into antineutrino energy. This ν[over ¯]_{e} energy spectrum is provided to the community, and an excess of events relative to the Huber model is found in the 5-6 MeV region. When a Gaussian bump is fitted to the excess, the data-model χ^{2} value is improved, corresponding to a 2.4σ significance.

Nonfuel Antineutrino Contributions in the High Flux Isotope Reactor.

Reactor neutrino experiments have seen major improvements in precision in recent years. With the experimental uncertainties becoming lower than those from theory, carefully considering all sources of ν ¯ e is important when making theoretical predictions. One source of ν ¯ e that is often neglected arises from the irradiation of the nonfuel materials in reactors. The ν ¯ e rates and energies from these sources vary widely based on the reactor type, configuration, and sampling stage during the reactor cycle and have to be carefully considered for each experiment independently. In this article, we present a formalism for selecting the possible ν ¯ e sources arising from the neutron captures on reactor and target materials. We apply this formalism to the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory, the ν ¯ e source for the the Precision Reactor Oscillation and Spectrum Measurement (PROSPECT) experiment. Overall, we observe that the nonfuel ν ¯ e contributions from HFIR to PROSPECT amount to 1% above the inverse beta decay threshold with a maximum contribution of 9% in the 1.8-2.0 MeV range. Nonfuel contributions can be particularly high for research reactors like HFIR because of the choice of structural and reflector material in addition to the intentional irradiation of target material for isotope production. We show that typical commercial pressurized water reactors fueled with low-enriched uranium will have significantly smaller nonfuel ν ¯ e contribution.

Measurement of the Antineutrino Spectrum from

This Letter reports the first measurement of the ^{235}U ν[over ¯]_{e} energy spectrum by PROSPECT, the Precision Reactor Oscillation and Spectrum experiment, operating 7.9 m from the 85 MW_{th} highly enriched uranium (HEU) High Flux Isotope Reactor. With a surface-based, segmented detector, PROSPECT has observed 31678±304(stat) ν[over ¯]_{e}-induced inverse beta decays, the largest sample from HEU fission to date, 99% of which are attributed to ^{235}U. Despite broad agreement, comparison of the Huber ^{235}U model to the measured spectrum produces a χ^{2}/ndf=51.4/31, driven primarily by deviations in two localized energy regions. The measured ^{235}U spectrum shape is consistent with a deviation relative to prediction equal in size to that observed at low-enriched uranium power reactors in the ν[over ¯]_{e} energy region of 5-7 MeV.

Upper limits on perturbations of nuclear decay rates induced by reactor electron antineutrinos.

We report the results of an experiment conducted near the High Flux Isotope Reactor of Oak Ridge National Laboratory, designed to address the question of whether a flux of reactor-generated electron antineutrinos (ν¯e) can alter the rates of weak nuclear interaction induced decays of 54Mn, 22Na, and 60Co. This experiment has small statistical errors but, when systematic uncertainties are included, has null results. Perturbations greater than one part in 104 are excluded at 95% confidence level in ß± decay and electron capture processes, in the presence of an antineutrino flux of 3 × 1012 cm-2s-1. The present experimental methods are applicable to a wide range of radionuclides. Improved sensitivity in future experiments can be anticipated as we continue to better understand and reduce the dominant systematic uncertainties.

First Search for Short-Baseline Neutrino Oscillations at HFIR with PROSPECT.

This Letter reports the first scientific results from the observation of antineutrinos emitted by fission products of ^{235}U at the High Flux Isotope Reactor. PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, consists of a segmented 4 ton ^{6}Li-doped liquid scintillator detector covering a baseline range of 7-9 m from the reactor and operating under less than 1 m water equivalent overburden. Data collected during 33 live days of reactor operation at a nominal power of 85 MW yield a detection of 25 461±283 (stat) inverse beta decays. Observation of reactor antineutrinos can be achieved in PROSPECT at 5σ statistical significance within 2 h of on-surface reactor-on data taking. A reactor model independent analysis of the inverse beta decay prompt energy spectrum as a function of baseline constrains significant portions of the previously allowed sterile neutrino oscillation parameter space at 95% confidence level and disfavors the best fit of the reactor antineutrino anomaly at 2.2σ confidence level.

[Effects of tobacco tax increase on cigarette consumption and the impact on health policy]. / Auswirkungen der Tabaksteuererhöhungen in Deutschland auf den Tabakkonsum und Konsequenzen für die Gesundheitspolitik.

The purpose of this study is to analyse the recent development of tobacco taxes and demand for cigarettes in Germany and to describe consequences for health policy. A descriptive analysis of aggregated data of the Federal Statistical Office is used to show the development of tax income and consumer behaviour with regard to the degree of substitution between differently taxed tobacco products. From 1993 to 2002 the demand for cigarettes increased nearly continuously. In 2003 the demand for industrial cigarettes went down by 8.6% and in 2004 by 15.8%. The difference between taxes and prices of industrial cigarettes and substitutes increased over the time period and still continues to increase. Tax and price differences between tobacco products led to partial compensation of the decreasing demand for industrial cigarettes. Therefore a tax increase on substitute products like fine cut tobacco is recommended. There is still a lack of longitudinal epidemiological data on smoking behaviour in Germany that could affirm effects of tobacco taxation.

[Cost-effectiveness of prevention of coronary disease in Germany]. / Kosteneffektivität der Prävention der koronaren Herzkrankheit in Deutschland.

It is generally accepted that the incidence of coronary heart disease can effectively be reduced by strengthening prevention. At the same time, it is still unclear how large the effects of life-style oriented preventive measurements such as diet and exercising are in everyday life. Furthermore, there is an ongoing debate on what measurements are effective. Thus, against the background of dwindling financial resources in health care the input of health economic evaluation is explicated. General issues of health economic evaluation are presented. After that, an overview on the current findings of cost-effectiveness in primary prevention of coronary heart disease is given. Risk factors are separately discussed. It is demonstrated that preventive measurements dealing especially with hypertension and hypercholesterolemia can be cost-effective.

[Cost-effectiveness of coronary heart disease prevention]. / Kosten-Effektivität der KHK-Prävention.

Most experts agree that prevention of coronary heart disease (CHD) should be enforced. However doubt remains about how extensively pharmacological treatment should be applied. In the presence of strong financial constraints both issues emphasize the importance of health economic analyses in this area. This article describes important principles in health economics. As the effect of preventive measures can only be recognized after a considerable time lag, a long-term perspective has to be chosen. A suitable parameter are the costs per life year saved, which can be compared between otherwise completely different procedures. The assessment of different therapies depends strongly on parameters such as relative risk reduction, discount rate and costs for prevention. However it was shown that prevention with statins and anti-hypertensive therapy can be cost-effective, as the mortality reduction and hence the increase in life expectancy can be considerable. Further research is necessary, e.g., to investigate possible reductions of other vascular diseases, to acquire more knowledge about long-term cost-consequences.

[Cost effectiveness of lipid lowering therapy]. / Kosteneffektivität der lipidsenkenden Therapie.

BACKGROUND: Due to increasing pressure to save money in the health care sector economical evaluations become more and more important. The following article deals with cost-effectiveness analyses regarding lipid-lowering therapy. Results are discussed in the light of methodological issues. COMPARISON OF EFFECTIVENESS: The choice of life years gained as effectiveness parameter facilitates the comparison of different therapies. Non-pharmacological therapies were able to achieve a reduction of risk factors, but a mortality reduction has not been proven so far. COST-EFFECTIVENESS OF STATINS: Own analyses from the perspective of the social insurance demonstrate that statins are cost-effective in secondary prevention of coronary heart disease (CHD). This confirms results from the viewpoint of the statutory health insurance under additional consideration of interaction between the various sectors of the social insurance in Germany. In primary prevention the cost-effectiveness is strongly related to the initial CHD risk. For which risk groups the therapy with statins is both effective and efficient depends on the underlying assumptions. Overall accepted threshold values for cost-effective therapies could be reached at a yearly risk of coronary heart disease of about 1.5%. CONCLUSION: The results should be considered by decision makers in the evaluation of statin therapy.

[Coronary disease and social security. A simulation model on cost analysis]. / Die koronare Herzkrankheit und die Sozialversicherung. Ein Simulationsmodell zur Kostenanalyse.

A Monte Carlo simulation model is presented which allows an assessment of the costs for coronary heart disease (CHD) (from a social security perspective) to be made over a time interval of 10 years. The difference between a CHD population and a normal population is calculated whereby the CHD population corresponds in terms of age and gender distribution to a German population with existing hypercholesteremia. The data were generated from the results of the German Cardiovascular Prevention Trial (DHP), a population was determined which represents the age group of the 45- to 65-year-old German population. Both direct as well as indirect costs were taken into account. The model simulates 2 submodels: 1. CHD is already present in the observed population. 2. A proportion of the observed cases of hypercholesteremia develop CHD over a time interval of 10 years, whereby normal distribution of the events is assumed. From the social security perspective, the cumulative costs of CHD for the observed age group who already have CHD amount to approximately 59 billion DM in 10 years (see Table 4). On the assumption that CHD develops during the course of these 10 years and that the population does not already present with CHD at the start of the simulation model, the costs are calculated to be about 41 billion DM (see Table 3). Numerous sensitivity analyses were carried out which showed that the assumption of the direct costs per case/year were highly sensitive (see Figure 1). The special advantage of the model is the perspective chosen, since social security is considered as a whole and interactions between individual branches of social security become transparent.

[Cost-benefit analysis of an evidence-based secondary prevention of coronary heart diseases by statins. An analysis for Germany from a social security perspective]. / Kosten-Nutzen-Analyse einer evidenzbasierten Sekundärprävention koronarer Herzkrankheiten durch Statine. Eine Analyse für Deutschland aus Perspektive der Sozialversicherung.

BACKGROUND: Lowering of the cholesterol level is of central importance in the prevention of coronary heart disease. Although the clinical benefits of treatment with statins have been shown in numerous studies, economic considerations are also being taken increasingly into account for the decision process about health care benefits. With this background, a cost-benefit analysis was carried out for statin treatment. METHODS: Based on a cost analysis for coronary heart disease carried out by the authors from a social security standpoint, the net prevention costs for secondary prevention in Germany were assessed. The ICD-9 codes 410-414 were assigned to coronary heart disease. In addition to the direct costs of treatment for coronary heart disease, loss of premiums for social security, savings on old age pensions, related pension claims and wage compensations over a time period of 10 years were also quantified in the cost analysis. Furthermore, prevention through medication for the 45- to 64-year-old coronary heart disease patients was considered. Costs for prevention were assessed on the basis of the mean dosages of all medications on the market according to the Rote Liste (German Formulary). A risk reduction of 30% was assumed and numerous univariate sensitivity analyses were carried out. RESULTS: Depending on which parameters were varied, there were pronounced differences in the results. The most favourable cost-benefit relation was achieved for the preventive measures in 400,000 patients with net prevention costs of 1.08 billion DM (2.16 billion DM for 800,000 patients) for a duration of medical preventive care of 5 years. The highest net prevention costs of 3.47 billion DM for 400,000 coronary heart disease patients (or 6.93 billion DM for 800,000 patients) resulted when maximum prices for statins were assumed. In the setting taken as base analysis, approximately 25% of the prevention costs are accounted for by cost saving through prevention. DISCUSSION: The transfer of clinical study results into clinical practice is associated with uncertainties which necessitate comprehensive sensitivity analyses. The costs of coronary heart disease were shown to be highly sensitive to the cost-benefit relationship. Although from an overall social security perspective, the direct costs of treatment and the loss of premiums were balanced by reduced expenditure (pension savings), coronary heart disease does lead to a financial burden on the social security. CONCLUSION: This financial burden is decreased by prevention of coronary heart disease. Part of the costs of statin therapy can be covered in every situation by cost savings through the avoidance of coronary heart disease. Even complex simulation models, that uses realistic assumptions, could only determine the costs of an evidence-based secondary prevention of coronary heart disease unprecisely, because the worst case and the best case vary with the factor 7.

[Costs of coronary heart diseases over the remaining life time in coronary heart disease cases--an analysis of the current status of coronary heart disease cases in Germany from the social perspective]. / Kosten koronarer Herzkrankheiten über die verbleibende Lebenszeit von KHK-Fällen--Eine Analyse des aktuellen Bestandes an KHK-Fällen in Deutschland aus gesellschaftlicher Perspektive.

UNLABELLED: Cardiovascular diseases are the major cause of death not only in Germany. Coronary heart diseases result in substantial disability and loss of productivity and contribute to escalating costs of health care. OBJECTIVE: It was our objective to estimate the costs of CHD for the German population from the perspective of the society. The characteristic of this approach is the calculating of costs until the approximated end of life. METHODS: In the study, all health care costs concerning CHD in Germany were allocated to age, sex, health care sector and primary diagnosis on the basis of comprehensive data on morbidity, mortality, direct and indirect costs. For the estimate of indirect costs the human capital approach was taken. Considered as cases were all patients hospitalized in the reference year (1996). The costs of this cohort in 1996 and up to their protected end of life were estimated. It was taken into account that, in comparison to the general population, life expectancy of cases with risk factors or CHD would have been reduced. In calculating indirect costs, gender and age specific unemployment rates were considered. All future costs were discounted by 4% from the reference year onward. RESULTS: Direct costs are approximately 39 billion DM discounted at 4%, indirect costs total 73 billion DM. The average cost per case (including morbidity and mortality) until the approximated end of life is nearly 125,000 DM. CONCLUSION: In our cost analysis, the indirect costs are higher than the direct costs. For the future, it will be important to estimate the costs of prevalent cases until the end of life and to compare the influence of different interventions on these parameters and on the whole budget of the social security system.