Evaluating the cost-effectiveness of percutaneous closure of a patent foramen ovale versus medical management in patients with a cryptogenic stroke: from the UK payer perspective

Aims: Percutaneous closure of a patent foramen ovale (PFO) is known to lower the risk of recurrent stroke in patients with a cryptogenic stroke. However, the economic implications of transcatheter PFO closure are less well known. From a UK payer perspective, a detailed economic appraisal of PFO closure was performed for prevention of recurrent ischemic stroke in patients with a PFO who had experienced a cryptogenic stroke.

Materials and methods: A Markov cohort model was constructed using a 5-year time-horizon with a patient mean age of 45.2 years, reflecting the characteristics reported in the REDUCE trial. Transition probabilities, clinical inputs, costs, and utility values were ascertained from published and national costing sources. Total costs, incremental costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios were calculated, utilizing a discount rate of 3.5%. A range of univariate and probabilistic sensitivity analyses were also performed.

Results: When applying a willingness-to-pay (WTP) threshold of £20,000/QALY in accordance with NICE guidelines, PFO closure compared with antiplatelet therapy alone showed a beneficial cost/QALY of £18,584, attained at 4 years. Applying discount rates of 0% and 6% had a negligible effect on the base-case model findings. PFO closure demonstrated a 76.9% probability of being cost-effective at a WTP threshold of £20,000/QALY at a 5-year time-horizon.

Limitations: This model focused specifically on UK stroke patients and typically enrolled young (mean age <65 years old) patients. Hence, caution should be taken when comparing data vs non-UK populations, and it remains unclear how older patients might have affected cost-effectiveness findings, as the risk of paradoxical embolism can persist as patients age.

Conclusion: Percutaneous closure of a PFO is cost-effective compared with antiplatelet therapy alone, underlining the economic benefits potentially afforded by this treatment in selected patients.     

Nonparametric estimation of convergence of interest rates: Effects on bond pricing

We present and estimate a model of short term interest rate dynamics where we incorporate the convergent behavior of interest rates implied by the transition to EMU. We apply this model to data of two EMU countries - Spain and Italy - and compare the performance, in terms of accuracy of bond pricing, of this two-factor convergence model with alternative specifications. Nonparametric techniques are used for the estimation of the processes. The two-factor model which accounts for the convergence with Europe of the domestic economies, obtains better results, especially for short-term assets, than alternative models. The results of the nonparametric specifications are shown to be significantly better than those of parametric alternatives.JEL Classification: E43, C14We would like to thank Adrian Pagan and Eduardo Schwartz for their invaluable feedback, encouragement and patience. We also would like to thank the editor, two anonymous referees and participants at the Symposium of Economic Analysis (Barcelona, December 1999), the Australasian Meeting of the Econometric Society (Sydney, July 1999), the 2000 European Meeting of the Financial Management Association (Edinburgh, July 2000) and seminars at the Australian National University, Canberra, and at the University of New South Wales, Sydney, for their comments and suggestions. All errors remain our sole responsibility. Financial assistance from the Fundación Ramó n Areces, Madrid, Spain, and the Asociación de Amigos de la Universidad de Navarra, Pamplona, Spain, is gratefully acknowledged.     

The Strategic Social Map of a Nongovernmental Organization

Currently, the traditional states-nation, as far as their social commitments are concerned, are giving way to the nongovernmental organizations (NGO). These organizations have a mission, strategy, and goals different from those organizations looking simply for profits. Nevertheless, NGOs are concerned about using management and information systems at least as good as those used by private companies. Organizations try to develop a social strategy taking their social responsibility as starting point. In this paper, the authors describe how to fix the organization mission, its strategy and goals, and also how to make its action map. A strategy proposal will be described, as well as the way on how to put it into practice. The main goals of this paper is to describe the mission, strategy, and goals of the organization; design its strategic social map; fix the limits of the organization's action; apply the theoretical model to a NGO; and design an information model in order to manage the strategic development. The authors would like to express their gratitude to M. Dolors Celma Benaiges, lecturer at the Escola Universitària del Maresme, Universitat Pompeu Fabra, for her assistance reviewing and translating the paper.     

Are More Innovative Firms Less Vulnerable to New Environmental Regulation?

Compliance with pollution limits and standards requires firms to implement adaptation processes that are not only costly themselves but also affect future profits in as much as they modify production systems and methods. This paper attempts to respond to the question of how technological knowledge moderates the effect that the implementation of a new environmental regulation has on the results of affected firms. The regulation selected for this study is the Integrated Pollution Prevention and Control Act (IPPC). A Multivariate Regression Model (MVRM) has been applied to the regulatory event. The most important implication of this paper is that technological knowledge prepares a firm for adapting to a greater environmental demand such as may be derived from a new regulation. This paper has been developed under the objectives of the CREVALOR Research Group (DGA-Spain). Moreover, it has been financed by the MEC-FEDER Research Project SEJ2005-07341.     

Interregional Trade Linkages and the Commercial Role: The Spanish Case

The development of a national or regional economy depends on its own actions as much as on those of its commercial partners. Trade transmits economic events from one economy to another. The type and the degree of interdependence between territories—regions or countries—determines the consequences of external actions in a region. Multipliers translate the effects of a change in one variable on the others. Using an input–output scheme to express interregional commercial flows, some coefficients are developed to classify and identify the role that each region plays in interregional trade. An empirical application of the methodology on Spanish Comunidades Autonomas is presented. A preliminary version of this paper was presented at the Fifty-Eight International Atlantic Economic Conference, Chicago, October 7–10, 2004. The authors greatly appreciate the comments and suggestions from the participants at the meeting. The authors also wish to thank an anonymous referee and editor for their constructive suggestions and comments. This research was partially supported by the DGI project SEJ2004-07924/ECON.     

Promising politicians,rational voters,and election outcomes

Overwhelming anecdotal evidence suggests that politicians often promise more during an election campaign than they are willing or able to deliver once elected. In this paper, we present two signaling models to explain this phenomenon. In the first model, two candidates maximize their share of the vote. In the second model both try to convince the median voter. In each model, candidates rationally distort their true policy position. Voters, however, are not fooled. Upon observing election promises, they can rationally infer the true position of each candidate. Hence, the election outcome is not affected.JEL Classification: D72, D82The author thanks Peter Kooreman, Wilko Letterie, Bert Schoonbeek, and two anonymous referees for useful comments. Financial support from The Netherlands Organization for Scientific Research (NWO) is gratefully acknowledged.     

The Case for International Coordination of Electricity Regulation: Evidence from the Measurement of Efficiency in South America

A decade of experience has shown that monitoring the performance of public and private monopolies is the hardest part of electricity sector reform in South America—because operators control most of the information needed for effective regulation. South American electricity regulators can reduce this information asymmetry by increasing international coordination and relying on comparative measures of efficiency. To make it possible for them to do so, countries should harmonize their regulatory databases and develop methodologies for making comparisons. This paper uses data envelopment analysis and stochastic frontier analysis to estimate the efficiency of South America's main electricity distribution companies. Both approaches allow regulators to use relatively simple tests to check the robustness of their findings, strengthening their positions at regulatory hearings.     

Environmental taxes and strategic delegation

This paper analyzes a managerial delegation model in which the government chooses an environmental tax to control environmental damage. By giving the managers of firms an incentive scheme based on a linear combination of profit and sales revenue, we show that firm owners have to pay a higher environmental tax and both environmental damage and social welfare increase compared to the profit-maximization case. Financial support from UPV (Subvención a grupos, 2001), UPV (HB-8238/2000) and MEC (BEC 2000-0301) is gratefully acknowledged. We would like to thank A. Saracho and two referees for helpful comments. The usual disclaimer applies.     

An empirical investigation of the effect of borrowing constraints on Spanish consumption

Abstract. This work analyses the relevance of borrowing constraints on the intertemporal behaviour of Spanish non-durable consumption. We estimate Euler equations with cohort data extracted from the “Encuesta Continua de Presupuestos Familiares” (ECPF) for the period 1985–1993. The results are robust to the use of different estimators to eliminate fixed individual effects, to different specifications of the model, to the effect of uncertainty and to the presence of habits in consumption. Our results allow us to conclude that non-durable consumption of a considerable fraction of the Spanish population is affected by borrowing constraints. At the same time, and in accordance with similar results for other countries, we confirm that borrowing constraints are especially important for the young. The author acknowledges the grant received from the Conselleria de Cultura, Educación y Ciencia de la Generalitat Valènciana, as part of its grant's programme for stays in foreign universities and the financial support by DGICYT grants SEC99-0820 and SEC 2002-00667. The author also acknowledges the hospitality of the Department of Economics at University College London (UCL) and of the Departamento de Análisis Económico de la Universidad Nacional de Educación a Distancia. This work has been presented in the XXV Simposio de Análisis Económico, held in Bellaterra (Spain) in December 2000. Finally, the author acknowledges comments by J. E. Boscá and two anonymous referees that have contributed to improving the final version of the paper.