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91.
Several complicating issues arise in evaluating the returns to research into varietal improvements for perennial crops compared with annual crops. We elucidate and address these issues in the context of a case study of research aiming to develop varieties that are resistant to Pierce's disease (PD) of grapevines. PD imposes costs of over $100 million per year on the California grape industry, even with public PD control programs in place. Research projects to develop PD resistant varieties of grapevines are at various stages of completion. We describe the economic problems posed by PD, document the research programs undertaken to address the disease and present an economic assessment of the returns to the investment, which are conditional on other policies. Using a simulation model of the market for California winegrapes, we estimate the benefits from research, development and adoption of PD‐resistant vines as ranging from $4 million to $129 million annually over a 50‐year horizon, depending on the length of the R&D lag and the rate of adoption. In addition to these specific quantitative results the paper offers insight into the broader question of economic evaluation of damage‐mitigation technology for perennial crops.  相似文献   
92.
[目的][方法]利用全国297个规模养鸡场2011—2015年的调查数据,采用成本收益法及样本均值T检验讨论疫病净化对养鸡场成本、收入和利润的影响。[结果](1)从总体收益角度来看,蛋鸡场的净化收益高于肉鸡场,祖代及以上场的净化收益高于其他代次,东部地区养鸡场的净化收益相比中西部地区更佳。(2)从单只鸡净收益角度来看,疫病净化对单只肉鸡的收益影响大于蛋鸡,对混合代养鸡场单只鸡的收益影响大于其他代次。目前,仅有华东地区、华南地区和西北地区的已净化养鸡场单只鸡的净收益大于未净化场,其余区域均低于未净化场。(3)除2011年外,2012—2015年期间已净化养鸡场的总收益及单只鸡净收益均高于未净化场。并且随着时间的推移,已净化养鸡场单只鸡净收益与未净化养鸡场之间的差距正在扩大。[结论]开展疫病净化可以提高养鸡场的经济效益。  相似文献   
93.
史太琴 《价值工程》2014,(24):147-148
通过对水泥生产过程中存在的职业病危害因素进行辨识,积极采取有效的控制措施,切实保护劳动者的身心健康,预防和减少职业病的发生。  相似文献   
94.
A higher growth rate of the service sector prices, rather than prices in the manufacturing sector, through time is known as cost disease in the service sector. This paper investigates supply and demand-side reasons for cost disease. First, we present an analysis of the supply side of the cost disease, when services and manufacturing play their role both in the intermediate and final demand. Second, we consider a CES utility function for the consumer, which is a function of two commodity services and manufacturing. The results indicate that there are two reasons for cost disease to occur from the supply side in an economy: first, when the growth rate of total factor productivity and technological progress in services is less than that in the manufacturing sector, and second, when the elasticity of substitution between labor and manufacturing input in the services production function is large and elasticity of substitution in manufacturing production function is small. From the demand side, the result shows that the cost disease occurred if the growth rate of the income elasticity of service is more than the manufacturing sector through time.  相似文献   
95.
Objective: To evaluate the cost-effectiveness of second-line nilotinib vs dasatinib among patients with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (Ph+?CML-CP) who are resistant or intolerant to imatinib, from a US third-party perspective.

Methods: A lifetime partitioned survival model was developed to compare the costs and effectiveness of nilotinib vs dasatinib, which included four health states: CP on treatment, CP post-discontinuation, progressive disease (accelerated phase [AP] or blast crisis [BC]), and death. Time on treatment, progression-free survival, and overall survival of nilotinib and dasatinib were estimated using real-world comparative effectiveness data. Parametric survival models were used to extrapolate outcomes beyond the study period. Drug treatment costs, medical costs, and adverse event costs were obtained from the literature and publicly available databases. Utilities of health states were derived from the literature. Incremental cost-effectiveness ratios, including incremental cost per life-year (LY) gained and incremental cost per quality-adjusted life-year (QALY) gained, were estimated comparing nilotinib and dasatinib. Deterministic sensitivity analyses were performed by varying patient characteristics, cost, and utility inputs.

Results: Over a lifetime horizon, nilotinib-treated patients were associated with 11.7 LYs, 9.1 QALYs, and a total cost of $1,409,466, while dasatinib-treated patients were associated with 9.5 LYs, 7.3 QALYs, and a total cost of $1,422,122. In comparison with dasatinib, nilotinib was associated with better health outcomes (by 2.2 LYs and 1.9 QALYs) and lower total costs (by $12,655). Deterministic sensitivity analysis results showed consistent findings in most scenarios.

Limitations: In the absence of long-term real-world data, the lifetime projection could not be validated.

Conclusions: Compared with dasatinib, second-line nilotinib was associated with better life expectancy, better quality-of-life, and lower costs among patients with Ph+?CML-CP who were resistant or intolerant to imatinib.  相似文献   
96.
Aim: To estimate real-world cardiovascular disease (CVD) burden and value-based price range of evolocumab for a US-context, high-risk, secondary-prevention population.

Materials and methods: Burden of CVD was assessed using the UK-based Clinical Practice Research Datalink (CPRD) in order to capture complete CV burden including CV mortality. Patients on standard of care (SOC; high-intensity statins) in CPRD were selected based on eligibility criteria of FOURIER, a phase 3 CV outcomes trial of evolocumab, and categorized into four cohorts: high-risk prevalent atherosclerotic CVD (ASCVD) cohort (n?=?1448), acute coronary syndrome (ACS) (n?=?602), ischemic stroke (IS) (n?=?151), and heart failure (HF) (n?=?291) incident cohorts. The value-based price range for evolocumab was assessed using a previously published economic model. The model incorporated CPRD CV event rates and considered CV event reduction rate ratios per 1?mmol/L reduction in low-density lipoprotein-cholesterol (LDL-C) from a meta-analysis of statin trials by the Cholesterol Treatment Trialists Collaboration (CTTC), i.e. CTTC relationship.

Results: Multiple-event rates of composite CV events (ACS, IS, or coronary revascularization) per 100 patient-years were 12.3 for the high-risk prevalent ASCVD cohort, and 25.7, 13.3, and 23.3, respectively, for incident ACS, IS, and HF cohorts. Approximately one-half (42%) of the high-risk ASCVD patients with a new CV event during follow-up had a subsequent CV event. Combining these real-world event rates and the CTTC relationship in the economic model, the value-based price range (credible interval) under a willingness-to-pay threshold of $150,000/quality-adjusted life-year gained for evolocumab was $11,990 ($9,341–$14,833) to $16,856 ($12,903–$20,678) in ASCVD patients with baseline LDL-C levels ≥70?mg/dL and ≥100?mg/dL, respectively.

Conclusion: Real-world CVD burden is substantial. Using the observed CVD burden in CPRD and the CTTC relationship, the cost-effectiveness analysis showed that, accounting for uncertainties, the expected value-based price for evolocumab is higher than its current annual cost, as long as the payer discount off list price is greater than 20%.  相似文献   
97.
Background: The cost-effectiveness of a heart failure management intervention can be further informed by incorporating the expected benefits and costs of future survival.

Methods: This study compared the long-term costs per quality-adjusted life year (QALY) gained from home-based (HBI) vs specialist clinic-based intervention (CBI) among elderly patients (mean age = 71 years) with heart failure discharged home (mean intervention duration = 12 months). Cost-utility analysis was conducted from a government-funded health system perspective. A Markov cohort model was used to simulate disease progression over 15 years based on initial data from a randomized clinical trial (the WHICH? study). Time-dependent hazard functions were modeled using the Weibull function, and this was compared against an alternative model where the hazard was assumed to be constant over time. Deterministic and probabilistic sensitivity analyses were conducted to identify the key drivers of cost-effectiveness and quantify uncertainty in the results.

Results: During the trial, mortality was the highest within 30 days of discharge and decreased thereafter in both groups, although the declining rate of mortality was slower in CBI than HBI. At 15 years (extrapolated), HBI was associated with slightly better health outcomes (mean of 0.59 QALYs gained) and mean additional costs of AU$13,876 per patient. The incremental cost-utility ratio and the incremental net monetary benefit (vs CBI) were AU$23,352 per QALY gained and AU$15,835, respectively. The uncertainty was driven by variability in the costs and probabilities of readmissions. Probabilistic sensitivity analysis showed HBI had a 68% probability of being cost-effective at a willingness-to-pay threshold of AU$50,000 per QALY.

Conclusion: Compared with CBI (outpatient specialized HF clinic-based intervention), HBI (home-based predominantly, but not exclusively) could potentially be cost-effective over the long-term in elderly patients with heart failure at a willingness-to-pay threshold of AU$50,000/QALY, albeit with large uncertainty.  相似文献   
98.
99.
Non-communicable diseases (NCDs) are the leading cause of global mortality. As the social and economic costs of NCDs have escalated, action is needed to tackle important causes of many NCD’s: low physical activity levels and unhealthy dietary behaviours. As these behaviours are driven by upstream factors, successful policy interventions are required that encourage healthy dietary behaviours, improve physical activity levels and reduce sedentary behaviours of entire populations. However, to date, no systematic research on the implementation and evaluation of policy interventions related to these health behaviours has been conducted across Europe. Consequently, no information on the merit, gaps, worth or utility of cross-European policy interventions is available, and no guidance or recommendations on how to enhance this knowledge across European countries exists. As part of the Joint Programming Initiative “A Healthy Diet for a Healthy Life” (JPI HDHL), 28 research institutes from seven European countries and New Zealand have combined their expertise to form the Policy Evaluation Network (PEN). PEN’s aim is to advance tools to identify, evaluate, implement and benchmark policies designed to directly or indirectly target dietary behaviours, physical activity, and sedentary behaviour in Europe, as well as to understand how these policies increase or decrease health inequalities. Using well-defined evaluation principles and methods, PEN will examine the content, implementation and impact of policies addressing dietary behaviour, physical activity levels and sedentary behaviour across Europe. It will realise the first steps in a bespoke health policy monitoring and surveillance system for Europe, and refine our knowledge of appropriate research designs and methods for the quantification of policy impact. It will contribute to our understanding of how to achieve successful transnational policy implementation and monitoring of these policies in different cultural, demographic or socioeconomic settings. PEN will consider equity and diversity aspects to ensure that policy actions are inclusive and culturally sensitive. Finally, based on three policy cases, PEN will illustrate how best to evaluate the implementation and impact of such policies in order to yield healthy diets and activity patterns that result in healthier lives for all European citizens.  相似文献   
100.
The willingness to pay (WTP) approach is increasingly being used in different disciplines to assess peoples’ readiness to accept change. This paper assesses the potential for two subunit vaccines for the prevention and control of bovine tuberculosis and paratuberculosis in cattle. A survey of beef and dairy farmers was conducted across Canada to identify factors that influence their WTP for subunit vaccines. Estimated results of the interval‐data model indicate that the size of a farmer’s cattle herd, neighbourhood effect, and buyer recommendations for vaccination significantly influence farmers’ WTP while veterinarians appear to be the most critical pathway for farmers to source information on new vaccine options. The mean willingness to pay amounts for both vaccines reveals that farmers are likely to use the vaccines if the costs are kept at reasonable level.  相似文献   
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