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91.
Background:

Venous thromboembolism (VTE), comprised of deep vein thrombosis (DVT) and pulmonary embolism (PE), is commonly treated with a low-molecular-weight heparin such as enoxaparin plus a vitamin K antagonist (VKA) to prevent recurrence. Administration of enoxaparin?+?VKA is hampered by complexities of laboratory monitoring and frequent dose adjustments. Rivaroxaban, an orally administered anticoagulant, has been compared with enoxaparin?+?VKA in the EINSTEIN trials. The objective was to evaluate the cost-effectiveness of rivaroxaban compared with enoxaparin?+?VKA as anticoagulation treatment for acute, symptomatic, objectively-confirmed DVT or PE.

Methods:

A Markov model was built to evaluate the costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios associated with rivaroxaban compared to enoxaparin?+?VKA in adult patients treated for acute DVT or PE. All patients entered the model in the ‘on-treatment’ state upon commencement of oral rivaroxaban or enoxaparin?+?VKA for 3, 6, or 12 months. Transition probabilities were obtained from the EINSTEIN trials during treatment and published literature after treatment. A 3-month cycle length, US payer perspective ($2012), 5-year time horizon and a 3% annual discount rate were used.

Results:

Treatment with rivaroxaban cost $2,448 per-patient less and was associated with 0.0058 more QALYs compared with enoxaparin?+?VKA, making it a dominant economic strategy. Upon one-way sensitivity analysis, the model’s results were sensitive to the reduction in index VTE hospitalization length-of-stay associated with rivaroxaban compared with enoxaparin?+?VKA. At a willingness-to-pay threshold of $50,000/QALY, probabilistic sensitivity analysis showed rivaroxaban to be cost-effective compared with enoxaparin?+?VKA approximately 76% of the time.

Limitations:

The model did not account for the benefits associated with an oral and minimally invasive administration of rivaroxaban. ‘Real-world’ applicability is limited because data from the EINSTEIN trials were used in the model. Also, resource utilization and costs were based on the US healthcare system.

Conclusion:

Rivaroxaban is a cost-effective option for anticoagulation treatment of acute VTE patients.  相似文献   
92.
We study the business‐cycle behavior of segmented labor markets with flexibility at the margin (e.g., just affecting fixed‐term contracts). We present a matching model with temporary and permanent jobs (i) where there is a gap in the firing costs associated with these types of jobs and (ii) where there are restrictions in the creation and duration of fixed‐term contracts. We show that a labor market with ``flexibility at the margin'' increases the unemployment volatility with respect to one that is fully regulated. This analysis yields new insights into the interpretation of the recent volatility changes witnessed in the OECD area.  相似文献   
93.
Objective: To assess long-term healthcare costs related to ischemic stroke and systemic embolism (stroke/SE) and major bleeding (MB) events in patients with non-valvular atrial fibrillation (NVAF) treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Materials and methods: Optum’s Clinformatics Data Mart database from 1/2009–12/2016 was analyzed. Adult patients with ≥1 stroke/SE hospitalization (index date) were matched 1:1 to patients without stroke/SE (random index date), based on propensity scores. Patients with an MB event were matched to patients without MB. All patients had an NOAC dispensing overlapping index date, ≥12?months of eligibility pre-index date, and ≥1 NVAF diagnosis. The observation period spanned from the index date until the earliest date of death, switch to warfarin, end of insurance coverage, or end of data availability. Mean costs were evaluated: (1) per-patient-per-year (PPPY) and (2) at 1, 2, 3, and 4?years using Lin's method.

Results: The cost differences were, respectively, $48,807 and $28,298 PPPY for NOAC users with stroke/SE (n?=?1,340) and those with MB (n?=?3,774) events compared to controls. Cost differences of patients with vs without stroke/SE were $49,876, $51,627, $57,822, and $60,691 at 1, 2, 3, and 4?years post-index, respectively (p?p?Limitations: Limitations include unobserved confounders, coding and/or billing inaccuracies, limited sample sizes over longer follow-up, and the under-reporting of mortality for deaths occurring after 2011.

Conclusions: The incremental healthcare costs incurred by patients with vs without stroke/SE was nearly twice as high as those of patients with vs without MB. Moreover, each additional year up to 4?years after the first event was associated with an incremental cost for patients with a stroke/SE or MB event compared to those without an event.  相似文献   
94.
ABSTRACT

This paper considers the extent to which the monetary policy operations of three major central banks can be regarded as an application of Proportional-Integral-Derivative (PID) control rules. The paper outlines the general PID framework and estimates a series of dynamic models to identify how interest rate policy adjustments are affected by the rate of inflation and the level of macroeconomic activity. The paper examines data for the UK, the USA and the Eurozone. The results suggest that the PID rules can provide a useful theoretical and empirical framework for estimating central bank responses to the inflation and macroeconomic activity variables by improving the explanatory power of the Taylor rule model and determining the effect of the parameters.  相似文献   
95.
Using data from the NLSY79, we structurally estimate a dynamic model of the life cycle decisions of young women. The women make sequential joint decisions about school attendance, work, marriage, fertility, and welfare participation. We use the model to perform counterfactual simulations designed to shed light on three questions: (1) How much of observed minority–majority differences in behavior can be attributed to differences in labor market opportunities, marriage market opportunities, and preference heterogeneity? (2) How does the welfare system interact with these factors to augment those differences? (3) How can new cohorts that grow up under the new welfare system (Temporary Aid for Needy Families) be expected to behave compared to older cohorts?  相似文献   
96.
A carbon tax is often cited by economists as an effective instrument to mitigate greenhouse gas emissions, but there is little political interest in the United States. In light of this political unpopularity, we develop and examine a net-revenue constrained carbon tax and subsidy program. The optimal revenue constrained tax and subsidy schedule based on our utility maximization model taxes energy sources with high emissions to energy price ratio, and subsidizes sources with low emissions to energy price ratios. This approach may be more palatable than a traditional carbon tax because it can change the relative price of low and high emissions energy sources while providing a mechanism to limit net tax increases and energy price increases. We find that a constrained tax/subsidy program provides welfare gains relative to a no-tax scenario. Welfare gains are estimated to be 1% and 36% of the welfare gains from a Pigouvian tax for the motor fuels industry and electric power industry, respectively. In contrast, subsidies for low-emitting energy sources funded from general tax funds rather than from high-emission energy tax revenues lead to welfare decreases substantially below our proposed tax/subsidy policy approach.  相似文献   
97.
98.
Test-retest studies help establish the reliability of contingent valuation (CV) responses but must confront the problem that the initial response may influence subsequent responses, and thus weaken conclusions. We develop a model that tests the influence of heterogeneous preferences and previous responses. By estimating a model of sportfishing, we show that correlation between answers to a CV question is induced by heterogeneous preferences.  相似文献   
99.
An overlapping generations model of an exchange economy with two sources of uncertainty is considered. Individuals have a finite expected life span and uncertain annual income. Conditions concerning birth, death, inheritance and bequests are fully specified. Under such conditions, the existence of a stationary Markovian equilibrium is established in some generality, and several explicitly solvable examples are examined in detail. Received August 6, 2001; revised version received March 12, 2002 Published online: November 11, 2002  相似文献   
100.
This paper assesses to what extent differences in the characteristics of individuals (micro‐level perspective) and country‐specific factors (macro‐level perspective) can explain country differences with respect to material deprivation levels. Thus, our work aims to simultaneously consider the macro dimension and the predominantly individually‐oriented study field of material deprivation using multilevel techniques. We make use of the European Union Statistics on Income and Living Conditions. Our results show that country‐specific factors seem to be much more relevant than individual effects in explaining country differences in material deprivation. We estimate that the introduction of country‐specific factors reduces the proportion of total variance due to between‐country differences in deprivation by 72.7 percent, while individual‐level variables reduce this proportion by only 9.4 percent. We also show, through interaction variables, that the effect of sociodemographic characteristics can be shaped by institutional and structural factors, especially by the level of GDP.  相似文献   
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