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121.
Objective:

Results of randomized clinical trials (RCT) demonstrate that novel oral anticoagulants (NOAC) are effective therapies for reducing the risk of stroke in non-valvular atrial fibrillation (NVAF). Prior medical cost avoidance studies have used warfarin event rates from RCTs, which may differ from patients receiving treatment in a real-world (RW) setting, where the quality of care may not be the same as in a RCT. The purpose of this study was to estimate the change in medical costs related to stroke and major bleeding for each NOAC (apixaban, dabigatran, and rivoraxaban) relative to warfarin in a RW NVAF population.

Methods:

Patients (n?=?23,525) with a diagnosis of NVAF during 2007–2010 were selected from a Medco population of US health plans. Stroke and major bleeding excluding intracranial hemorrhage (MBEIH) events were identified using diagnosis codes on medical claims. RW reference event rates were calculated during periods of warfarin exposure. RW event rates for NOACs were estimated by multiplying the corresponding relative risk (RR) from the RCTs by each reference rate. Absolute risk reductions (ARR) or number of events avoided per patient year were then estimated. Changes in medical costs associated with each NOAC were calculated by applying the ARR to the 1-year cost for each event. Costs for stroke and MBEIH were obtained from the literature. Drug and international normalized ratio monitoring costs were not considered in this analysis.

Results:

Compared to RW warfarin, use of apixaban and dabigatran resulted in total (stroke plus MBEIH) medical cost reductions of $1245 and $555, respectively, during a patient year. Rivaroxaban resulted in a medical cost increase of $144.

Conclusions:

If relative risk reductions demonstrated in RCTs persist in a RW setting, apixaban would confer the greatest medical cost savings vs warfarin, resulting from significantly lower rates of both stroke and MBEIH.  相似文献   
122.
In this study, the wavelet multiscale model is applied to selected assets to hedge time-dependent exposure of an agent with a preference for a certain hedging horizon. Based on the in-sample and out-of-sample portfolio variances, the wavelet-based generalized autoregressive conditional heteroskedasticity (GARCH) model produces the lowest variances. From a utility standpoint, wavelet networks combined with GARCH have the highest utility. Finally, the wavelet-GARCH model has the lowest minimum capital risk requirements. Overall, the wavelet GARCH and wavelet networks offer improvements over traditional hedging models.  相似文献   
123.
124.
In this article, I identify challenges to the loss distribution approach in modeling operational risk. I propose a scenario-based methodology for operational risk assessment, which recognizes that each risk can occur under a number of wide-ranging scenarios and that association between risks may behave differently for different scenarios. The model that is developed internally in the company provides a practical quantitative assessment of risk exposure that reflects a deep understanding of the company and its environment, making the risk calculation more responsive to the actual state, ensuring that the company is attending to its key operational risks. In this model qualitative and quantitative approaches are combined to build a loss distribution for individual and aggregate operational risk exposure. The model helps to portray the company's internal control systems and aspects of business environment. These features can help the company increase its operational efficiency, reduce loss from undesirable incidents, and maintain the integrity of internal control.  相似文献   
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126.
The aim of this study was to uncover patterns of pedestrian crashes. In the first stage, 34,178 pedestrian-involved crashes occurred in Iran during a four-year period were grouped into homogeneous clusters using a clustering analysis. Next, some in-cluster and inter-cluster crash patterns were analysed. The clustering analysis yielded six pedestrian crash groups. Car/van/pickup crashes on rural roads as well as heavy vehicle crashes were found to be less frequent but more likely to be fatal compared to other crash clusters. In addition, after controlling for crash frequency in each cluster, it was found that the fatality rate of each pedestrian age group as well as the fatal crash involvement rate of each driver age group varies across the six clusters. Results of present study has some policy implications including, promoting pedestrian safety training sessions for heavy vehicle drivers, imposing limitations over elderly heavy vehicle drivers, reinforcing penalties toward under 19 drivers and motorcyclists. In addition, road safety campaigns in rural areas may be promoted to inform people about the higher fatality rate of pedestrians on rural roads. The crash patterns uncovered in this study might also be useful for prioritizing future pedestrian safety research areas.  相似文献   
127.
The birth of the first in vitro fertilized baby, followed by further advances in the field of assisted reproductive technology (ART) has made this technology one of the most attractive tourism innovations among the different categories of medical tourism. In addition, factors such as legal, moral, religious and ethical issues play important roles in choosing reproductive tourism destinations. The aim of this study was to examine the factors influencing destination choice in infertile couples who referred to the Isfahan Fertility and Infertility Center in Isfahan, Iran. Field evaluation was carried out based on a documentary survey and questionnaire completed by interviewers. Among a target group of 80 infertile couples, 67 were interviewed. The majority of participants in this study were Muslim couples who traveled for reproductive tourism to Iran. It can be concluded that religious affinity may have paramount importance in reproductive medical tourism for Muslim infertile couples.  相似文献   
128.
129.
We examine the long-run equilibrium relation between the net flow of funds into equity mutual funds and the S&P 500 index. Applying the Engle and Granger error correction methodology followed by a state space procedure, we find that the levels of the stock market are influenced by the net flow of funds into equity mutual funds. Our findings indicate that the U.S. equity market appears to be rationally adjusting to a structural change in the behavior of the U.S. investing public.  相似文献   
130.
This article proposes a new algorithm for grouping problems that is a grouping version of league championship algorithm (GLCA). We compare the performance of GLCA with several well-known algorithms published in the present literature and select a set of 20 most widely used benchmarks of cell formation sample problems posing as a grouping problem. We used a truncated geometric algorithm to find the number of initial cells. Our computations reveal that GLCA can reach the best-known solution for 17 of the 20 benchmark problems, and improve the solution of three others with a 1.4% average gap.  相似文献   
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