Cost-effectiveness analysis of implementing an antimicrobial stewardship program in critical care units

Aims: To evaluate the cost-effectiveness of antimicrobial stewardship (AS) program implementation focused on critical care units based on assumptions for the Spanish setting.

Materials and methods: A decision model comparing costs and outcomes of sepsis, community-acquired pneumonia, and nosocomial infections (including catheter-related bacteremia, urinary tract infection, and ventilator-associated pneumonia) in critical care units with or without an AS was designed. Model variables and costs, along with their distributions, were obtained from the literature. The study was performed from the Spanish National Health System (NHS) perspective, including only direct costs. The Incremental Cost-Effectiveness Ratio (ICER) was analysed regarding the ability of the program to reduce multi-drug resistant bacteria. Uncertainty in ICERs was evaluated with probabilistic sensitivity analyses.

Results: In the short-term, implementing an AS reduces the consumption of antimicrobials with a net benefit of €71,738. In the long-term, the maintenance of the program involves an additional cost to the system of €107,569. Cost per avoided resistance was €7,342, and cost-per-life-years gained (LYG) was €9,788. Results from the probabilistic sensitivity analysis showed that there was a more than 90% likelihood that an AS would be cost-effective at a level of €8,000 per LYG.

Limitations: Wide variability of economic results obtained from the implementation of this type of AS program and short information on their impact on patient evolution and any resistance avoided.

Conclusions: Implementing an AS focusing on critical care patients is a long-term cost-effective tool. Implementation costs are amortized by reducing antimicrobial consumption to prevent infection by multidrug-resistant pathogens.     

The importance of flexible hazard functions in the analysis of organizational survival data -- experiences from a cohort of Swedish commercial banks

The survival pattern of Swedish commercial banks during the period 1830--1990 is studied by parametric and non-parametric event-history methods. In particular we study the sensitivity of the conclusions reached with respect to the model used. It is found that the hazard is inversely U-shaped, which means that models that cannot allow for this type of hazard run into difficulties. Thus two of the most popular approaches in the analysis of event history data, the Gompertz and the Weibull models produce misleading results regarding the development of the death risk of banks over time. As regards the effect of explanatory variables on survival, on the other hand, most models are found to be robust and even in cases of misspecified baseline hazards, the estimated effects of the explanatory variables do not seem to be seriously wrong.     

Family Background and Economic Status in Finland

The importance of family background for economic outcomes is analyzed, using a Finnish data set. The estimates for intergenerational and sibling correlations in earnings are comparatively low. By estimating the magnitude of family influence conditional on parental earnings, children with poor parents are found to have lower intergenerational elasticities, while the sibling resemblance is higher. Children with rich parents have higher intergenerational elasticities and the sibling resemblance is also higher, except for daughters. The results also indicate that the largest share of the intergenerational correlation is transmitted through observed characteristics, such as education and, in particular, occupation.
JEL classification : D 1; D 3; J 6     

High precision registration of complicated longitudinal and cross-sectional data

In the article are given examples showing how, by using musical notation in registering (complicated) developments, considerably more qualitative variables may be taken into account than we were used to; furthermore, the temporal element may be represented with a degree of precision that corresponds to our needs. In case of cross-sectional data modifications of musical notation may be used. However, we have to recognize that there are also variables, maybe important ones, that — for several reasons — cannot be registered with a very high precision. Other complications are hinted at. The method described is rather a working method by means of which to improve the basis for a further quantitative analysis than a method suitable for showing final research results.     

Exports, economic growth and the consolidation of peace in El Salvador

The pillars of inclusive growth in El Salvador have to be nontraditional export growth, investment, and government determination to reduce income inequality and poverty. This article analyzes the key obstacles to the development of a competitive and dynamic export sector: Dutch Disease driven by aid and remittances, a significant decline in real wages, and lack of productivity growth. Policies can and must focus on productivity growth rather than wage repression, in the pursuit of peace consolidation and long-term competitiveness.     

On the Validity of the Wiener Process Assumption in Option Pricing Models: Contradictory Evidence from Taiwan

This study tests the validity of the critical assumption underlying the option pricing model that the log form of the stock price movements follows the Wiener process, i.e., stock price movements follow a geometric Brownian motion. Using data compiled from the Taiwan Stock Exchange (TSE), this study's major empirical findings are as follows: first, the null hypothesis that the log of the stock prices is normally distributed is rejected; second, the null hypothesis that the stock price in log form has mean [ln P _s + (µ- ²)_t] and variance t is rejected; third, the null hypothesis that successive non-overlapping increments of the log of the stock price are independent from each other is also rejected. These empirical findings undermine the validity of the Wiener process assumption which is fundamental to many option pricing models.     

Fundamental Drivers of Dependence in REIT Returns

We analyse the empirical relationships between firm fundamentals and the dependence structure between individual REIT and stock market returns. In contrast to previous studies, we distinguish between the average systematic risk of REITs and their asymmetric risk in the sense of a disproportionate likelihood of joint negative return clusters between REITs and the stock market. We find that REITs with low systematic risk are typically small, with low short-term momentum, low turnover, high growth opportunities and strong long-term momentum. Holding systematic risk constant, the main driving forces of asymmetric risk are leverage and, to some extent, short-term momentum. Specifically, we find that leverage has an asymmetric effect on REIT return dependence that outweighs the extent to which it increases the average sensitivity of REIT equity to market fluctuations, explaining the strong negative impact of leverage on firm performance especially during crisis periods that has been documented in recent empirical work.     

Asset pricing with adaptive learning

We study the extent to which self-referential adaptive learning can explain stylized asset pricing facts in a general equilibrium framework. In particular, we analyze the effects of recursive least squares and constant gain algorithms in a production economy and a Lucas type endowment economy. We find that (a) recursive least squares learning has almost no effects on asset price behavior, since the algorithm converges relatively fast to rational expectations, (b) constant gain learning may contribute towards explaining the stock price and return volatility as well as the predictability of excess returns in the endowment economy but (c) in the production economy the effects of constant gain learning are mitigated by the persistence induced by capital accumulation. We conclude that in the context of these two commonly used models, standard linear self-referential learning does not resolve the asset pricing puzzles observed in the data.     

The impact of electricity prices on foreign direct investment: evidence from the European Union

We examine the impact of electricity price variation on net FDI (%GDP) inflows in countries of the European Union. We use panel data of 27 EU countries for a period of 2003 – 2013. We show that electricity prices of south-western and north-eastern EU countries did not converge to one price until now. Dynamic panel data analysis using system GMM shows that besides unit labour costs, tax rates and competitive disadvantage in secondary education, also higher electricity prices reduce countries’ ability to attract FDI. The immediate effects are statistically significant across both sub-regions analysed: in the short run, a 10% increase in electricity prices leads to a decrease in net FDI inflows as a share of GDP by 0.4 percentage points for the south-western and 0.33 for the north-eastern region. In the long run, the response is 0.60 percentage points for south-western and 0.48 for north-eastern regions. Policies should aim at reducing electricity market price differences on the European level through investment in transborder transmission capacity; reductions in FDI, when environmental policy increases after-tax electricity prices, should be countered by other tax reductions as well as harmonization of property rights, absence of corruption and labour market regulations at best-practice level.