Economic modelling of costs associated with outcomes reported for type 2 diabetes mellitus (T2DM) patients in the CANVAS and EMPA-REG cardiovascular outcomes trials

Aims: To model direct medical costs associated with reductions in cardiovascular disease (CVD) events in T2DM patients reported in the CANVAS and EMPA-REG trials, which assessed the cardiovascular safety of canagliflozin and empagliflozin, respectively.

Materials and methods: Costs were modeled from a US managed care organization (MCO) perspective for the CVD outcomes included in both trials: three-point major adverse cardiovascular event (MACE) and its components (cardiovascular-related death, nonfatal myocardial infarction, nonfatal stroke), as well as heart failure requiring hospitalization. The rate of CVD events averted (difference between study drug and placebo) was projected to the portion of an MCO T2DM population matching the respective trial’s inclusion criteria. A targeted literature search for paid amounts directly associated with each CVD event provided the unit costs, which were applied to the projected number of events averted, to calculate costs avoided per member per year (PMPY). One-way sensitivity analyses were performed on events averted, unit costs, and percentages of trial-applicable patients.

Results: Based on three-point MACE events averted, costs avoided PMPY of $6.17 (range: $1.27–$10.94) for CANVAS and $2.75 ($0.19–$4.83) for EMPA-REG were estimated. Costs avoided for individual components of MACE ranged from $0.77 to $3.84 PMPY for CANVAS and from -$0.97 (additional costs) to $1.54 for EMPA-REG. PMPY costs avoided for heart failure were $2.72 for CANVAS and $1.32 for EMPA-REG.

Limitations and conclusions: Models assumed independent, non-recurrent outcomes and were restricted to medical costs directly associated with the trial-reported events. The reductions in CVD events in T2DM patients reported for both CANVAS and EMPA-REG project to a positive cost avoidance for these events in an MCO population. The analysis did not include an assessment of the impact on total cost, as the costs associated with adverse events, drug utilization or other clinical outcomes were not examined.     

Do pensions foster education? An empirical perspective

The paper examines the effect of population ageing on public education spending. On the one hand, ageing is expected to have a negative effect on education, as an increasing number of retirees results in ‘intergenerational conflict’ and, hence, the condemnation of education expenditure. On the other hand, ageing, in combination with pay-as-you-go pension systems, offers incentives for the working-age generation to invest in the public education of the young in order to ‘reap’ the benefits (that is, higher income tax/contributions) of their greater future productivity. Empirical evidence derived from the application of a fixed effects approach to panel data for OECD countries shows that the increasing share of elderly people has a non-linear effect on education spending. This indicates a certain degree of intergenerational conflict. Nevertheless, we find that future population ageing, which reinforces the mechanism linking public education and pensions, reflects positively on education expenditure. Furthermore, by disaggregating total education expenditure by educational levels, we observe that this effect is led by levels of non-compulsory education, probably as a reflection of the direct connection to labor productivity.     

Adam Smith on lotteries: an interpretation and formal restatement

The paper concerns a neglected aspect of the Wealth of Nations (with the notable exception of D. Levy 1999 Levy, D. M. 1999. “Adam Smith’s Katallactic Model of Gambling: Approbation from the Spectator.” Journal of the History of Economic Thought 21 (1): 81–91. doi:10.1017/S1053837200002868.[Crossref] , [Google Scholar]), dealing directly with decision under risk. In a few pages from book I, chapter 10, Adam Smith explicitly named “lotteries” various objects of choice (possible occupations, or investment opportunities, for instance) and provided an analysis which standard expected utility glasses would hardly fit. Taking this into account allows a better understanding of the part played by typical characters like the “projector” or the “sober man”, in such matters as Smith’s conception of entrepreneurship or of the credit market. The use of some modern concepts in decision analysis (inverse stochastic dominance, rank dependent utility, prudence toward risk), is a means to show the existence, in Smith’s work, of an original theory from decision under risk, where his analysis of lotteries in the Wealth of Nations is consistent with statements from his moral philosophy on asymmetric sensitivity to gains and losses and to the regulating part played by the impartial spectator.     

Do brain drain and poverty result from coordination failures?

The bidirectional causal links between high-skilled emigration and poverty can give rise to multiple equilibria and coordination failures. Two countries sharing identical characteristics may end up in either a “low poverty-low brain drain” equilibrium or in a “high poverty-high brain drain” equilibrium. In this paper, we build a model which endogenizes high-skilled emigration and economic performances in order to derive the conditions under which multiplicity occurs. After identifying country-specific parameters, we find that in the majority of developing countries, the best equilibrium is selected and that the observed brain drain is inevitable. In 22 small developing countries however, the worse equilibrium prevails, implying that poverty and brain drain are increased by coordination failure. These countries require appropriate development policies, such as a temporary subsidization of the repatriation of their high-skilled expatriates. Our results are robust to the inclusion of a brain gain mechanism.     

Modeling Cyclical Asymmetries in European Imports

This paper applies smooth transition models to capture the nonlinear behavior in the imports data of six major European economies and to assess whether such nonlinearities are related to business cycle asymmetries. Two classes of switch between regimes are considered: endogenously determined transition that assumes nonlinearities are generated by idiosyncratic components specific to foreign trade, and exogenous transition based on GDP growth as a more direct indicator of the cyclical state of the economy. The results support the proposition that the dynamics of imports are nonlinear. In Belgium, France, Spain, and the United Kingdom, regimes change over the business cycle, while in Germany and Italy the switch between regimes is endogenous. National characteristics play a role in defining the position of extreme regimes, the smoothness of the transition, and local dynamics within each state.Previous versions of this article have been presented at the 57th International Atlantic Economic Conference (Lisbon, Portugal, March 10–14, 2004) and at the VII Encuentro de Economía Aplicada (Vigo, Spain, June 3–5, 2004). The authors thank the conference participants and an anonymous referee for their comments.     

Theϕ-divergence statistic in bivariate multinomial populations including stratification

ϕ-divergence statistics quantify the divergence between a joint probability measure and the product of its marginal probabilities on the basis of contingency tables. Asymptotic properties of these statistics are investigated either considering random sampling or stratified random sampling with proportional allocation and independence among strata. To finish same tests of hypotheses of independence are presented. The research in this paper was supported in part by DGICYT Grants No. PS91-0387 and No. PB91-0155. Their financial support is gratefully acknowledged.     

What Prevents Firms from Advancing in their Environmental Strategy?

The aim of this paper is to analyze the determinants of the strategic environmental behavior of firms and, more specifically, the external and internal barriers that limit and sometimes even prevent the environmental adaptation. The analysis focuses on a sample of industrial firms that have at least three workers and that are located in Aragón, a region situated in the northeast of Spain. In order to achieve this objective, first the theoretical literature on the topic is reviewed. Subsequently, from the firms which were sampled, the existence of an underlying structure among the totality of barriers is studied. Finally, this structure is analyzed in order to determine if it has any influence on the degree of proactivity of the firm’s environmental strategy.

Returns from social capital in open source software networks

Open Source Software projects base their operation on a collaborative structure for knowledge exchange in the form of provision or reception of information, expertise and feedback on the creation of source code. Here, we address the direction of these knowledge flows among projects throughout social networks and their impact on project success. We identify the roles of membership or contribution that individuals play within projects. We found that connections through contributors who bring their knowledge to the project, improve project success, and that connection through members, who transfer their knowledge towards other projects, enhance project success. Finally, we found that ties through shared membership and contributions hamper project success. The analysis of knowledge flows and their impact on project success imply a translation of returns from investment in social capital, where investment takes the shape of knowledge flows and the returns mean the projects’ diffusion over the network.