Improvement of the cost-benefit analysis algorithm for high-rise construction projects

Directory of Open Access Journals (Sweden)

Gafurov Andrey

2018-01-01

Full Text Available The specific nature of high-rise investment projects entailing long-term construction, high risks, etc. implies a need to improve the standard algorithm of cost-benefit analysis. An improved algorithm is described in the article. For development of the improved algorithm of cost-benefit analysis for high-rise construction projects, the following methods were used: weighted average cost of capital, dynamic cost-benefit analysis of investment projects, risk mapping, scenario analysis, sensitivity analysis of critical ratios, etc. This comprehensive approach helped to adapt the original algorithm to feasibility objectives in high-rise construction. The authors put together the algorithm of cost-benefit analysis for high-rise construction projects on the basis of risk mapping and sensitivity analysis of critical ratios. The suggested project risk management algorithms greatly expand the standard algorithm of cost-benefit analysis in investment projects, namely: the “Project analysis scenario” flowchart, improving quality and reliability of forecasting reports in investment projects; the main stages of cash flow adjustment based on risk mapping for better cost-benefit project analysis provided the broad range of risks in high-rise construction; analysis of dynamic cost-benefit values considering project sensitivity to crucial variables, improving flexibility in implementation of high-rise projects.

Improvement of the cost-benefit analysis algorithm for high-rise construction projects

Science.gov (United States)

Gafurov, Andrey; Skotarenko, Oksana; Plotnikov, Vladimir

2018-03-01

The specific nature of high-rise investment projects entailing long-term construction, high risks, etc. implies a need to improve the standard algorithm of cost-benefit analysis. An improved algorithm is described in the article. For development of the improved algorithm of cost-benefit analysis for high-rise construction projects, the following methods were used: weighted average cost of capital, dynamic cost-benefit analysis of investment projects, risk mapping, scenario analysis, sensitivity analysis of critical ratios, etc. This comprehensive approach helped to adapt the original algorithm to feasibility objectives in high-rise construction. The authors put together the algorithm of cost-benefit analysis for high-rise construction projects on the basis of risk mapping and sensitivity analysis of critical ratios. The suggested project risk management algorithms greatly expand the standard algorithm of cost-benefit analysis in investment projects, namely: the "Project analysis scenario" flowchart, improving quality and reliability of forecasting reports in investment projects; the main stages of cash flow adjustment based on risk mapping for better cost-benefit project analysis provided the broad range of risks in high-rise construction; analysis of dynamic cost-benefit values considering project sensitivity to crucial variables, improving flexibility in implementation of high-rise projects.

Nuclear fuel cycle cost estimation and sensitivity analysis of unit costs on the basis of an equilibrium model

International Nuclear Information System (INIS)

Kim, S. K.; Ko, W. I.; You, S. R.; Gao, R. X.

2015-01-01

This paper examines the difference in the value of the nuclear fuel cycle cost calculated by the deterministic and probabilistic methods on the basis of an equilibrium model. Calculating using the deterministic method, the direct disposal cost and Pyro-SFR (sodium-cooled fast reactor) nuclear fuel cycle cost, including the reactor cost, were found to be 66.41 mills/kWh and 77.82 mills/kWh, respectively (1 mill = one thousand of a dollar, i.e., 10-3 $). This is because the cost of SFR is considerably expensive. Calculating again using the probabilistic method, however, the direct disposal cost and Pyro-SFR nuclear fuel cycle cost, excluding the reactor cost, were found be 7.47 mills/kWh and 6.40 mills/kWh, respectively, on the basis of the most likely value. This is because the nuclear fuel cycle cost is significantly affected by the standard deviation and the mean of the unit cost that includes uncertainty. Thus, it is judged that not only the deterministic method, but also the probabilistic method, would also be necessary to evaluate the nuclear fuel cycle cost. By analyzing the sensitivity of the unit cost in each phase of the nuclear fuel cycle, it was found that the uranium unit price is the most influential factor in determining nuclear fuel cycle costs.

Cost analysis of youth violence prevention.

Science.gov (United States)

Sharp, Adam L; Prosser, Lisa A; Walton, Maureen; Blow, Frederic C; Chermack, Stephen T; Zimmerman, Marc A; Cunningham, Rebecca

2014-03-01

Effective violence interventions are not widely implemented, and there is little information about the cost of violence interventions. Our goal is to report the cost of a brief intervention delivered in the emergency department that reduces violence among 14- to 18-year-olds. Primary outcomes were total costs of implementation and the cost per violent event or violence consequence averted. We used primary and secondary data sources to derive the costs to implement a brief motivational interviewing intervention and to identify the number of self-reported violent events (eg, severe peer aggression, peer victimization) or violence consequences averted. One-way and multi-way sensitivity analyses were performed. Total fixed and variable annual costs were estimated at $71,784. If implemented, 4208 violent events or consequences could be prevented, costing $17.06 per event or consequence averted. Multi-way sensitivity analysis accounting for variable intervention efficacy and different cost estimates resulted in a range of $3.63 to $54.96 per event or consequence averted. Our estimates show that the cost to prevent an episode of youth violence or its consequences is less than the cost of placing an intravenous line and should not present a significant barrier to implementation.

Early assessment of the likely cost-effectiveness of a new technology: A Markov model with probabilistic sensitivity analysis of computer-assisted total knee replacement.

Science.gov (United States)

Dong, Hengjin; Buxton, Martin

2006-01-01

The objective of this study is to apply a Markov model to compare cost-effectiveness of total knee replacement (TKR) using computer-assisted surgery (CAS) with that of TKR using a conventional manual method in the absence of formal clinical trial evidence. A structured search was carried out to identify evidence relating to the clinical outcome, cost, and effectiveness of TKR. Nine Markov states were identified based on the progress of the disease after TKR. Effectiveness was expressed by quality-adjusted life years (QALYs). The simulation was carried out initially for 120 cycles of a month each, starting with 1,000 TKRs. A discount rate of 3.5 percent was used for both cost and effectiveness in the incremental cost-effectiveness analysis. Then, a probabilistic sensitivity analysis was carried out using a Monte Carlo approach with 10,000 iterations. Computer-assisted TKR was a long-term cost-effective technology, but the QALYs gained were small. After the first 2 years, the incremental cost per QALY of computer-assisted TKR was dominant because of cheaper and more QALYs. The incremental cost-effectiveness ratio (ICER) was sensitive to the "effect of CAS," to the CAS extra cost, and to the utility of the state "Normal health after primary TKR," but it was not sensitive to utilities of other Markov states. Both probabilistic and deterministic analyses produced similar cumulative serious or minor complication rates and complex or simple revision rates. They also produced similar ICERs. Compared with conventional TKR, computer-assisted TKR is a cost-saving technology in the long-term and may offer small additional QALYs. The "effect of CAS" is to reduce revision rates and complications through more accurate and precise alignment, and although the conclusions from the model, even when allowing for a full probabilistic analysis of uncertainty, are clear, the "effect of CAS" on the rate of revisions awaits long-term clinical evidence.

Cost analysis methodology of spent fuel storage

International Nuclear Information System (INIS)

1994-01-01

The report deals with the cost analysis of interim spent fuel storage; however, it is not intended either to give a detailed cost analysis or to compare the costs of the different options. This report provides a methodology for calculating the costs of different options for interim storage of the spent fuel produced in the reactor cores. Different technical features and storage options (dry and wet, away from reactor and at reactor) are considered and the factors affecting all options defined. The major cost categories are analysed. Then the net present value of each option is calculated and the levelized cost determined. Finally, a sensitivity analysis is conducted taking into account the uncertainty in the different cost estimates. Examples of current storage practices in some countries are included in the Appendices, with description of the most relevant technical and economic aspects. 16 figs, 14 tabs

Sensitivity analysis of floating offshore wind farms

International Nuclear Information System (INIS)

Castro-Santos, Laura; Diaz-Casas, Vicente

2015-01-01

Highlights: • Develop a sensitivity analysis of a floating offshore wind farm. • Influence on the life-cycle costs involved in a floating offshore wind farm. • Influence on IRR, NPV, pay-back period, LCOE and cost of power. • Important variables: distance, wind resource, electric tariff, etc. • It helps to investors to take decisions in the future. - Abstract: The future of offshore wind energy will be in deep waters. In this context, the main objective of the present paper is to develop a sensitivity analysis of a floating offshore wind farm. It will show how much the output variables can vary when the input variables are changing. For this purpose two different scenarios will be taken into account: the life-cycle costs involved in a floating offshore wind farm (cost of conception and definition, cost of design and development, cost of manufacturing, cost of installation, cost of exploitation and cost of dismantling) and the most important economic indexes in terms of economic feasibility of a floating offshore wind farm (internal rate of return, net present value, discounted pay-back period, levelized cost of energy and cost of power). Results indicate that the most important variables in economic terms are the number of wind turbines and the distance from farm to shore in the costs’ scenario, and the wind scale parameter and the electric tariff for the economic indexes. This study will help investors to take into account these variables in the development of floating offshore wind farms in the future

Sensitivity Analysis in Sequential Decision Models.

Science.gov (United States)

Chen, Qiushi; Ayer, Turgay; Chhatwal, Jagpreet

2017-02-01

Sequential decision problems are frequently encountered in medical decision making, which are commonly solved using Markov decision processes (MDPs). Modeling guidelines recommend conducting sensitivity analyses in decision-analytic models to assess the robustness of the model results against the uncertainty in model parameters. However, standard methods of conducting sensitivity analyses cannot be directly applied to sequential decision problems because this would require evaluating all possible decision sequences, typically in the order of trillions, which is not practically feasible. As a result, most MDP-based modeling studies do not examine confidence in their recommended policies. In this study, we provide an approach to estimate uncertainty and confidence in the results of sequential decision models. First, we provide a probabilistic univariate method to identify the most sensitive parameters in MDPs. Second, we present a probabilistic multivariate approach to estimate the overall confidence in the recommended optimal policy considering joint uncertainty in the model parameters. We provide a graphical representation, which we call a policy acceptability curve, to summarize the confidence in the optimal policy by incorporating stakeholders' willingness to accept the base case policy. For a cost-effectiveness analysis, we provide an approach to construct a cost-effectiveness acceptability frontier, which shows the most cost-effective policy as well as the confidence in that for a given willingness to pay threshold. We demonstrate our approach using a simple MDP case study. We developed a method to conduct sensitivity analysis in sequential decision models, which could increase the credibility of these models among stakeholders.

Cost-sensitive classification problem (Poster)

NARCIS (Netherlands)

Calders, T.G.K.; Pechenizkiy, M.

2012-01-01

In practical situations almost all classification problems are cost-sensitive or utility based one way or another. This exercise mimics a real situation in which students first have to translate a description into a datamining workflow, learn a prediction model, apply it to new data, and set up a

Process development and exergy cost sensitivity analysis of a hybrid molten carbonate fuel cell power plant and carbon dioxide capturing process

Science.gov (United States)

Mehrpooya, Mehdi; Ansarinasab, Hojat; Moftakhari Sharifzadeh, Mohammad Mehdi; Rosen, Marc A.

2017-10-01

An integrated power plant with a net electrical power output of 3.71 × 105 kW is developed and investigated. The electrical efficiency of the process is found to be 60.1%. The process includes three main sub-systems: molten carbonate fuel cell system, heat recovery section and cryogenic carbon dioxide capturing process. Conventional and advanced exergoeconomic methods are used for analyzing the process. Advanced exergoeconomic analysis is a comprehensive evaluation tool which combines an exergetic approach with economic analysis procedures. With this method, investment and exergy destruction costs of the process components are divided into endogenous/exogenous and avoidable/unavoidable parts. Results of the conventional exergoeconomic analyses demonstrate that the combustion chamber has the largest exergy destruction rate (182 MW) and cost rate (13,100 /h). Also, the total process cost rate can be decreased by reducing the cost rate of the fuel cell and improving the efficiency of the combustion chamber and heat recovery steam generator. Based on the total avoidable endogenous cost rate, the priority for modification is the heat recovery steam generator, a compressor and a turbine of the power plant, in rank order. A sensitivity analysis is done to investigate the exergoeconomic factor parameters through changing the effective parameter variations.

Applications of advances in nonlinear sensitivity analysis

Energy Technology Data Exchange (ETDEWEB)

Werbos, P J

1982-01-01

The following paper summarizes the major properties and applications of a collection of algorithms involving differentiation and optimization at minimum cost. The areas of application include the sensitivity analysis of models, new work in statistical or econometric estimation, optimization, artificial intelligence and neuron modelling.

Extended forward sensitivity analysis of one-dimensional isothermal flow

International Nuclear Information System (INIS)

Johnson, M.; Zhao, H.

2013-01-01

Sensitivity analysis and uncertainty quantification is an important part of nuclear safety analysis. In this work, forward sensitivity analysis is used to compute solution sensitivities on 1-D fluid flow equations typical of those found in system level codes. Time step sensitivity analysis is included as a method for determining the accumulated error from time discretization. The ability to quantify numerical error arising from the time discretization is a unique and important feature of this method. By knowing the relative sensitivity of time step with other physical parameters, the simulation is allowed to run at optimized time steps without affecting the confidence of the physical parameter sensitivity results. The time step forward sensitivity analysis method can also replace the traditional time step convergence studies that are a key part of code verification with much less computational cost. One well-defined benchmark problem with manufactured solutions is utilized to verify the method; another test isothermal flow problem is used to demonstrate the extended forward sensitivity analysis process. Through these sample problems, the paper shows the feasibility and potential of using the forward sensitivity analysis method to quantify uncertainty in input parameters and time step size for a 1-D system-level thermal-hydraulic safety code. (authors)

Risk-Sensitive Control with Near Monotone Cost

International Nuclear Information System (INIS)

Biswas, Anup; Borkar, V. S.; Suresh Kumar, K.

2010-01-01

The infinite horizon risk-sensitive control problem for non-degenerate controlled diffusions is analyzed under a 'near monotonicity' condition on the running cost that penalizes large excursions of the process.

Combined multi-criteria and cost-benefit analysis

DEFF Research Database (Denmark)

Moshøj, Claus Rehfeld

1996-01-01

The paper is an introduction to both theory and application of combined Cost-Benefit and Multi-Criteria Analysis. The first section is devoted to basic utility theory and its practical application in Cost-Benefit Analysis. Based on some of the problems encountered, arguments in favour...... of the application of utility-based Multi-Criteria Analyses methods as an extension and refinement of the traditional Cost-Benefit Analysis are provided. The theory presented in this paper is closely related the methods used in the WARP software (Leleur & Jensen, 1989). The presentation is however wider in scope.......The second section introduces the stated preference methodology used in WARP to create weight profiles for project pool sensitivity analysis. This section includes a simple example. The third section discusses how decision makers can get a priori aid to make their pair-wise comparisons based on project pool...

The Effect of Conditional Conservatism and Agency Cost on Investment-Cashflow Sensitivity

Directory of Open Access Journals (Sweden)

Bima Abdi Wibawa

2018-01-01

Full Text Available This research aims to give empirical evidence of the effect of conditional conservatism on company’s investment-cashflow sensitivity, and whether the impact is stronger in high agency cost firms compare to in low agency cost firms. This research uses dividend payout ratio to measure the agency cost because this study uses Indonesia as a research context where companies in Indonesia majority have concentrated ownership and funding through debt so that agency conflict that appears more dominant is the conflict of agency type two and three. This study uses the sample from manufacturing companies listed on Indonesia Stock Exchange during the period 2008-2012. The total observation in this research is 474 firm years, which 152 of the samples is classified as high agency cost firms and 322 sample as low agency cost firms. The result shows that as the recognition of economic losses becomes more timely, the sensitivity of firm investment to cashflow decreases. Conditional conservatism decreases investment-cashflow sensitivity in low agency cost firms but increases the sensitivity in high agency cost firms. In fact, before implementation of conditional conservatism, high agency cost firms have smaller investment cashflow sensitivity compared to the low agency cost one.

Sensitivity Analysis of the Critical Speed in Railway Vehicle Dynamics

DEFF Research Database (Denmark)

Bigoni, Daniele; True, Hans; Engsig-Karup, Allan Peter

2014-01-01

We present an approach to global sensitivity analysis aiming at the reduction of its computational cost without compromising the results. The method is based on sampling methods, cubature rules, High-Dimensional Model Representation and Total Sensitivity Indices. The approach has a general applic...

Decision tree sensitivity analysis for cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma)

International Nuclear Information System (INIS)

Kosuda, Shigeru; Watanabe, Masumi; Kobayashi, Hideo; Kusano, Shoichi; Ichihara, Kiyoshi

1998-01-01

Decision tree analysis was used to assess cost-effectiveness of chest FDG-PET in patients with a pulmonary tumor (non-small cell carcinoma, ≤Stage IIIB), based on the data of the current decision tree. Decision tree models were constructed with two competing strategies (CT alone and CT plus chest FDG-PET) in 1,000 patient population with 71.4% prevalence. Baselines of FDG-PET sensitivity and specificity on detection of lung cancer and lymph node metastasis, and mortality and life expectancy were available from references. Chest CT plus chest FDG-PET strategy increased a total cost by 10.5% when a chest FDG-PET study costs 0.1 million yen, since it increased the number of mediastinoscopy and curative thoracotomy despite reducing the number of bronchofiberscopy to half. However, the strategy resulted in a remarkable increase by 115 patients with curable thoracotomy and decrease by 51 patients with non-curable thoracotomy. In addition, an average life expectancy increased by 0.607 year/patient, which means increase in medical cost is approximately 218,080 yen/year/patient when a chest FDG-PET study costs 0.1 million yen. In conclusion, chest CT plus chest FDG-PET strategy might not be cost-effective in Japan, but we are convinced that the strategy is useful in cost-benefit analysis. (author)

A cost-effectiveness analysis of two different antimicrobial stewardship programs.

Science.gov (United States)

Okumura, Lucas Miyake; Riveros, Bruno Salgado; Gomes-da-Silva, Monica Maria; Veroneze, Izelandia

2016-01-01

There is a lack of formal economic analysis to assess the efficiency of antimicrobial stewardship programs. Herein, we conducted a cost-effectiveness study to assess two different strategies of Antimicrobial Stewardship Programs. A 30-day Markov model was developed to analyze how cost-effective was a Bundled Antimicrobial Stewardship implemented in a university hospital in Brazil. Clinical data derived from a historical cohort that compared two different strategies of antimicrobial stewardship programs and had 30-day mortality as main outcome. Selected costs included: workload, cost of defined daily doses, length of stay, laboratory and imaging resources used to diagnose infections. Data were analyzed by deterministic and probabilistic sensitivity analysis to assess model's robustness, tornado diagram and Cost-Effectiveness Acceptability Curve. Bundled Strategy was more expensive (Cost difference US$ 2119.70), however, it was more efficient (US$ 27,549.15 vs 29,011.46). Deterministic and probabilistic sensitivity analysis suggested that critical variables did not alter final Incremental Cost-Effectiveness Ratio. Bundled Strategy had higher probabilities of being cost-effective, which was endorsed by cost-effectiveness acceptability curve. As health systems claim for efficient technologies, this study conclude that Bundled Antimicrobial Stewardship Program was more cost-effective, which means that stewardship strategies with such characteristics would be of special interest in a societal and clinical perspective. Copyright © 2016 Elsevier Editora Ltda. All rights reserved.

A cost-effectiveness analysis of two different antimicrobial stewardship programs

Directory of Open Access Journals (Sweden)

Lucas Miyake Okumura

2016-05-01

Full Text Available There is a lack of formal economic analysis to assess the efficiency of antimicrobial stewardship programs. Herein, we conducted a cost-effectiveness study to assess two different strategies of Antimicrobial Stewardship Programs. A 30-day Markov model was developed to analyze how cost-effective was a Bundled Antimicrobial Stewardship implemented in a university hospital in Brazil. Clinical data derived from a historical cohort that compared two different strategies of antimicrobial stewardship programs and had 30-day mortality as main outcome. Selected costs included: workload, cost of defined daily doses, length of stay, laboratory and imaging resources used to diagnose infections. Data were analyzed by deterministic and probabilistic sensitivity analysis to assess model's robustness, tornado diagram and Cost-Effectiveness Acceptability Curve. Bundled Strategy was more expensive (Cost difference US$ 2119.70, however, it was more efficient (US$ 27,549.15 vs 29,011.46. Deterministic and probabilistic sensitivity analysis suggested that critical variables did not alter final Incremental Cost-Effectiveness Ratio. Bundled Strategy had higher probabilities of being cost-effective, which was endorsed by cost-effectiveness acceptability curve. As health systems claim for efficient technologies, this study conclude that Bundled Antimicrobial Stewardship Program was more cost-effective, which means that stewardship strategies with such characteristics would be of special interest in a societal and clinical perspective.

Automated sensitivity analysis: New tools for modeling complex dynamic systems

International Nuclear Information System (INIS)

Pin, F.G.

1987-01-01

Sensitivity analysis is an established methodology used by researchers in almost every field to gain essential insight in design and modeling studies and in performance assessments of complex systems. Conventional sensitivity analysis methodologies, however, have not enjoyed the widespread use they deserve considering the wealth of information they can provide, partly because of their prohibitive cost or the large initial analytical investment they require. Automated systems have recently been developed at ORNL to eliminate these drawbacks. Compilers such as GRESS and EXAP now allow automatic and cost effective calculation of sensitivities in FORTRAN computer codes. In this paper, these and other related tools are described and their impact and applicability in the general areas of modeling, performance assessment and decision making for radioactive waste isolation problems are discussed

Economic analysis of hydrogen production through a bio-ethanol steam reforming process: Sensitivity analyses and cost estimations

International Nuclear Information System (INIS)

Song, Hua; Ozkan, Umit S.

2010-01-01

In this study, the hydrogen selling price from ethanol steam reforming has been estimated for two different production scenarios in the United States, i.e. central production (150,000 kg H 2 /day) and distributed (forecourt) production (1500 kg H 2 /day), based on a process flowchart generated by Aspen Plus registered including downstream purification steps and economic analysis model template published by the U.S Department of Energy (DOE). The effect of several processing parameters as well as catalyst properties on the hydrogen selling price has been evaluated. 2.69/kg is estimated as the selling price for a central production process of 150,000 kg H 2 /day and 4.27/kg for a distributed hydrogen production process at a scale of 1500 kg H 2 /day. Among the parameters investigated through sensitivity analyses, ethanol feedstock cost, catalyst cost, and catalytic performance are found to play a significant role on determining the final hydrogen selling price. (author)

Sensitivity analysis on uncertainty variables affecting the NPP's LUEC with probabilistic approach

International Nuclear Information System (INIS)

Nuryanti; Akhmad Hidayatno; Erlinda Muslim

2013-01-01

One thing that is quite crucial to be reviewed prior to any investment decision on the nuclear power plant (NPP) project is the calculation of project economic, including calculation of Levelized Unit Electricity Cost (LUEC). Infrastructure projects such as NPP’s project are vulnerable to a number of uncertainty variables. Information on the uncertainty variables which makes LUEC’s value quite sensitive due to the changes of them is necessary in order the cost overrun can be avoided. Therefore this study aimed to do the sensitivity analysis on variables that affect LUEC with probabilistic approaches. This analysis was done by using Monte Carlo technique that simulate the relationship between the uncertainty variables and visible impact on LUEC. The sensitivity analysis result shows the significant changes on LUEC value of AP1000 and OPR due to the sensitivity of investment cost and capacity factors. While LUEC changes due to sensitivity of U 3 O 8 ’s price looks not quite significant. (author)

Cost-Sensitive Feature Selection of Numeric Data with Measurement Errors

Directory of Open Access Journals (Sweden)

Hong Zhao

2013-01-01

Full Text Available Feature selection is an essential process in data mining applications since it reduces a model’s complexity. However, feature selection with various types of costs is still a new research topic. In this paper, we study the cost-sensitive feature selection problem of numeric data with measurement errors. The major contributions of this paper are fourfold. First, a new data model is built to address test costs and misclassification costs as well as error boundaries. It is distinguished from the existing models mainly on the error boundaries. Second, a covering-based rough set model with normal distribution measurement errors is constructed. With this model, coverings are constructed from data rather than assigned by users. Third, a new cost-sensitive feature selection problem is defined on this model. It is more realistic than the existing feature selection problems. Fourth, both backtracking and heuristic algorithms are proposed to deal with the new problem. Experimental results show the efficiency of the pruning techniques for the backtracking algorithm and the effectiveness of the heuristic algorithm. This study is a step toward realistic applications of the cost-sensitive learning.

A Comprehensive Mathematical Programming Model for Minimizing Costs in A Multiple-Item Reverse Supply Chain with Sensitivity Analysis

Directory of Open Access Journals (Sweden)

Mahmoudi Hoda

2014-09-01

Full Text Available These instructions give you guidelines for preparing papers for IFAC conferences. A reverse supply chain is configured by a sequence of elements forming a continuous process to treat return-products until they are properly recovered or disposed. The activities in a reverse supply chain include collection, cleaning, disassembly, test and sorting, storage, transport, and recovery operations. This paper presents a mathematical programming model with the objective of minimizing the total costs of reverse supply chain including transportation, fixed opening, operation, maintenance and remanufacturing costs of centers. The proposed model considers the design of a multi-layer, multi-product reverse supply chain that consists of returning, disassembly, processing, recycling, remanufacturing, materials and distribution centers. This integer linear programming model is solved by using Lingo 9 software and the results are reported. Finally, a sensitivity analysis of the proposed model is also presented.

The cost of nurse-sensitive adverse events.

Science.gov (United States)

Pappas, Sharon Holcombe

2008-05-01

The aim of this study was to describe the methodology for nursing leaders to determine the cost of adverse events and effective levels of nurse staffing. The growing transparency of quality and cost outcomes motivates healthcare leaders to optimize the effectiveness of nurse staffing. Most hospitals have robust cost accounting systems that provide actual patient-level direct costs. These systems allow an analysis of the cost consumed by patients during a hospital stay. By knowing the cost of complications, leaders have the ability to justify the cost of improved staffing when quality evidence shows that higher nurse staffing improves quality. An analysis was performed on financial and clinical data from hospital databases of 3,200 inpatients. The purpose was to establish a methodology to determine actual cost per case. Three diagnosis-related groups were the focus of the analysis. Five adverse events were analyzed along with the costs. A regression analysis reported that the actual direct cost of an adverse event was dollars 1,029 per case in the congestive heart failure cases and dollars 903 in the surgical cases. There was a significant increase in the cost per case in medical patients with urinary tract infection and pressure ulcers and in surgical patients with urinary tract infection and pneumonia. The odds of pneumonia occurring in surgical patients decreased with additional registered nurse hours per patient day. Hospital cost accounting systems are useful in determining the cost of adverse events and can aid in decision making about nurse staffing. Adverse events add costs to patient care and should be measured at the unit level to adjust staffing to reduce adverse events and avoid costs.

Simulation-Based Approach to Operating Costs Analysis of Freight Trucking

Directory of Open Access Journals (Sweden)

Ozernova Natalja

2015-12-01

Full Text Available The article is devoted to the problem of costs uncertainty in road freight transportation services. The article introduces the statistical approach, based on Monte Carlo simulation on spreadsheets, to the analysis of operating costs. The developed model gives an opportunity to estimate operating freight trucking costs under different configuration of cost factors. Important conclusions can be made after running simulations regarding sensitivity to different factors, optimal decisions and variability of operating costs.

Neuraxial blockade for external cephalic version: Cost analysis.

Science.gov (United States)

Yamasato, Kelly; Kaneshiro, Bliss; Salcedo, Jennifer

2015-07-01

Neuraxial blockade (epidural or spinal anesthesia/analgesia) with external cephalic version increases the external cephalic version success rate. Hospitals and insurers may affect access to neuraxial blockade for external cephalic version, but the costs to these institutions remain largely unstudied. The objective of this study was to perform a cost analysis of neuraxial blockade use during external cephalic version from hospital and insurance payer perspectives. Secondarily, we estimated the effect of neuraxial blockade on cesarean delivery rates. A decision-analysis model was developed using costs and probabilities occurring prenatally through the delivery hospital admission. Model inputs were derived from the literature, national databases, and local supply costs. Univariate and bivariate sensitivity analyses and Monte Carlo simulations were performed to assess model robustness. Neuraxial blockade was cost saving to both hospitals ($30 per delivery) and insurers ($539 per delivery) using baseline estimates. From both perspectives, however, the model was sensitive to multiple variables. Monte Carlo simulation indicated neuraxial blockade to be more costly in approximately 50% of scenarios. The model demonstrated that routine use of neuraxial blockade during external cephalic version, compared to no neuraxial blockade, prevented 17 cesarean deliveries for every 100 external cephalic versions attempted. Neuraxial blockade is associated with minimal hospital and insurer cost changes in the setting of external cephalic version, while reducing the cesarean delivery rate. © 2015 The Authors. Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology.

Benefit-Cost Analysis of Integrated Paratransit Systems : Volume 6. Technical Appendices.

Science.gov (United States)

1979-09-01

This last volume, includes five technical appendices which document the methodologies used in the benefit-cost analysis. They are the following: Scenario analysis methodology; Impact estimation; Example of impact estimation; Sensitivity analysis; Agg...

Cost benefit analysis in diagnostic radiology: glossary and definitions

International Nuclear Information System (INIS)

Golder, W.

1999-01-01

Cost efficiency analyses in clinical radiology require the application of methods and techniques that are not yet part of the academic qualifications of the specialists. The procedures used are borrowed from economics, decision theory, applied social sciences, epidemiology and statistics. Many expressions hail from the angloamerican literature and are presently not yet germanized unequivocally. This survey is intended to present main terms of cost efficiency analysis in the English version as well as a German translation, to give a clear definition and, if necessary, explanatory notes, and to illustrate their application by means of concrete radiologic examples. The selection of the terms is based on the hierarchical models of health technology assessment resp. clinical outcome research by Fryback and Thronbury resp. Maisey and Hutton. In concrete terms, both the differences between benefit, outcomes, and utility and the differences between effectiveness, efficacy and efficiency and the differences between direct, indirect, intangible, and marginal costs are explained. True cost efficiency analysis is compared with cost effectiveness analysis, cost identification analysis, cost minimization analysis, and cost utility analysis. Applied social sciences are represented by the Medical Outcomes Study Short Form-36 and the QALY conception. From decision theory both the analysis of hypothetical alternatives and the Markov model are taken. Finally, sensitivity analysis and the procedures of combined statistical evaluation of comparable results (meta-analysis) are quoted. (orig.) [de

Sensitivity of nuclear fuel-cycle cost to uncertainties in nuclear data. Final report

International Nuclear Information System (INIS)

Becker, M.; Harris, D.R.

1980-11-01

An improved capability for assessing the economic implications of uncertainties in nuclear data and methods on the power reactor fuel cycle was developed. This capability is applied to the sensitivity analysis of fuel-cycle cost with respect to changes in nuclear data and related computational methods. Broad group sensitivities for both a typical BWR and a PWR are determined under the assumption of a throwaway fuel cycle as well as for a scenario under which reprocessing is allowed. Particularly large dollar implications are found for the thermal and resonance cross sections of fissile and fertile materials. Sensitivities for the throwaway case are found to be significantly larger than for the recycle case. Constrained sensitivities obtained for cases in which information from critical experiments or other benchmarks is used in the design calculation to adjust a parameter such as anti ν are compared with unconstrained sensitivities. Sensitivities of various alternate fuel cycles were examined. These included the extended-burnup (18-month) LWR cycle, the mixed-oxide (plutonium) cycle, uranium-thorium and denatured uranium-thorium cycles, as well as CANDU-type reactor cycles. The importance of the thermal capture and fission cross sections of 239 Pu is shown to be very large in all cases. Detailed, energy dependent sensitivity profiles are provided for the thermal range (below 1.855 eV). Finally, sensitivity coefficients are combined with data uncertainties to determine the impact of such uncertainties on fuel-cycle cost parameters

Sensitivity analysis

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003741.htm Sensitivity analysis To use the sharing features on this page, please enable JavaScript. Sensitivity analysis determines the effectiveness of antibiotics against microorganisms (germs) ...

Probabilistic sensitivity analysis incorporating the bootstrap: an example comparing treatments for the eradication of Helicobacter pylori.

Science.gov (United States)

Pasta, D J; Taylor, J L; Henning, J M

1999-01-01

Decision-analytic models are frequently used to evaluate the relative costs and benefits of alternative therapeutic strategies for health care. Various types of sensitivity analysis are used to evaluate the uncertainty inherent in the models. Although probabilistic sensitivity analysis is more difficult theoretically and computationally, the results can be much more powerful and useful than deterministic sensitivity analysis. The authors show how a Monte Carlo simulation can be implemented using standard software to perform a probabilistic sensitivity analysis incorporating the bootstrap. The method is applied to a decision-analytic model evaluating the cost-effectiveness of Helicobacter pylori eradication. The necessary steps are straightforward and are described in detail. The use of the bootstrap avoids certain difficulties encountered with theoretical distributions. The probabilistic sensitivity analysis provided insights into the decision-analytic model beyond the traditional base-case and deterministic sensitivity analyses and should become the standard method for assessing sensitivity.

National Variation in Urethroplasty Cost and Predictors of Extreme Cost: A Cost Analysis With Policy Implications.

Science.gov (United States)

Harris, Catherine R; Osterberg, E Charles; Sanford, Thomas; Alwaal, Amjad; Gaither, Thomas W; McAninch, Jack W; McCulloch, Charles E; Breyer, Benjamin N

2016-08-01

To determine which factors are associated with higher costs of urethroplasty procedure and whether these factors have been increasing over time. Identification of determinants of extreme costs may help reduce cost while maintaining quality. We conducted a retrospective analysis using the 2001-2010 Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS). The HCUP-NIS captures hospital charges which we converted to cost using the HCUP cost-to-charge ratio. Log cost linear regression with sensitivity analysis was used to determine variables associated with increased costs. Extreme cost was defined as the top 20th percentile of expenditure, analyzed with logistic regression, and expressed as odds ratios (OR). A total of 2298 urethroplasties were recorded in NIS over the study period. The median (interquartile range) calculated cost was $7321 ($5677-$10,000). Patients with multiple comorbid conditions were associated with extreme costs [OR 1.56, 95% confidence interval (CI) 1.19-2.04, P = .02] compared with patients with no comorbid disease. Inpatient complications raised the odds of extreme costs (OR 3.2, CI 2.14-4.75, P costs (OR 1.78, 95% CI 1.2-2.64, P = .005). Variations in patient age, race, hospital region, bed size, teaching status, payor type, and volume of urethroplasty cases were not associated with extremes of cost. Cost variation for perioperative inpatient urethroplasty procedures is dependent on preoperative patient comorbidities, postoperative complications, and surgical complexity related to graft usage. Procedural cost and cost variation are critical for understanding which aspects of care have the greatest impact on cost. Copyright © 2016 Elsevier Inc. All rights reserved.

Global sensitivity analysis using polynomial chaos expansions

International Nuclear Information System (INIS)

Sudret, Bruno

2008-01-01

Global sensitivity analysis (SA) aims at quantifying the respective effects of input random variables (or combinations thereof) onto the variance of the response of a physical or mathematical model. Among the abundant literature on sensitivity measures, the Sobol' indices have received much attention since they provide accurate information for most models. The paper introduces generalized polynomial chaos expansions (PCE) to build surrogate models that allow one to compute the Sobol' indices analytically as a post-processing of the PCE coefficients. Thus the computational cost of the sensitivity indices practically reduces to that of estimating the PCE coefficients. An original non intrusive regression-based approach is proposed, together with an experimental design of minimal size. Various application examples illustrate the approach, both from the field of global SA (i.e. well-known benchmark problems) and from the field of stochastic mechanics. The proposed method gives accurate results for various examples that involve up to eight input random variables, at a computational cost which is 2-3 orders of magnitude smaller than the traditional Monte Carlo-based evaluation of the Sobol' indices

Global sensitivity analysis using polynomial chaos expansions

Energy Technology Data Exchange (ETDEWEB)

Sudret, Bruno [Electricite de France, R and D Division, Site des Renardieres, F 77818 Moret-sur-Loing Cedex (France)], E-mail: bruno.sudret@edf.fr

2008-07-15

Global sensitivity analysis (SA) aims at quantifying the respective effects of input random variables (or combinations thereof) onto the variance of the response of a physical or mathematical model. Among the abundant literature on sensitivity measures, the Sobol' indices have received much attention since they provide accurate information for most models. The paper introduces generalized polynomial chaos expansions (PCE) to build surrogate models that allow one to compute the Sobol' indices analytically as a post-processing of the PCE coefficients. Thus the computational cost of the sensitivity indices practically reduces to that of estimating the PCE coefficients. An original non intrusive regression-based approach is proposed, together with an experimental design of minimal size. Various application examples illustrate the approach, both from the field of global SA (i.e. well-known benchmark problems) and from the field of stochastic mechanics. The proposed method gives accurate results for various examples that involve up to eight input random variables, at a computational cost which is 2-3 orders of magnitude smaller than the traditional Monte Carlo-based evaluation of the Sobol' indices.

Probability density adjoint for sensitivity analysis of the Mean of Chaos

Energy Technology Data Exchange (ETDEWEB)

Blonigan, Patrick J., E-mail: blonigan@mit.edu; Wang, Qiqi, E-mail: qiqi@mit.edu

2014-08-01

Sensitivity analysis, especially adjoint based sensitivity analysis, is a powerful tool for engineering design which allows for the efficient computation of sensitivities with respect to many parameters. However, these methods break down when used to compute sensitivities of long-time averaged quantities in chaotic dynamical systems. This paper presents a new method for sensitivity analysis of ergodic chaotic dynamical systems, the density adjoint method. The method involves solving the governing equations for the system's invariant measure and its adjoint on the system's attractor manifold rather than in phase-space. This new approach is derived for and demonstrated on one-dimensional chaotic maps and the three-dimensional Lorenz system. It is found that the density adjoint computes very finely detailed adjoint distributions and accurate sensitivities, but suffers from large computational costs.

The 2nu-SVM: A Cost-Sensitive Extension of the nu-SVM

National Research Council Canada - National Science Library

Davenport, Mark A

2005-01-01

.... In this report we review cost-sensitive extensions of standard support vector machines (SVMs). In particular, we describe cost-sensitive extensions of the C-SVM and the nu-SVM, which we denote the 2C-SVM and 2nu-SVM respectively...

Cost benefit analysis cost effectiveness analysis

International Nuclear Information System (INIS)

Lombard, J.

1986-09-01

The comparison of various protection options in order to determine which is the best compromise between cost of protection and residual risk is the purpose of the ALARA procedure. The use of decision-aiding techniques is valuable as an aid to selection procedures. The purpose of this study is to introduce two rather simple and well known decision aiding techniques: the cost-effectiveness analysis and the cost-benefit analysis. These two techniques are relevant for the great part of ALARA decisions which need the use of a quantitative technique. The study is based on an hypothetical case of 10 protection options. Four methods are applied to the data

Structure and sensitivity analysis of individual-based predator–prey models

International Nuclear Information System (INIS)

Imron, Muhammad Ali; Gergs, Andre; Berger, Uta

2012-01-01

The expensive computational cost of sensitivity analyses has hampered the use of these techniques for analysing individual-based models in ecology. A relatively cheap computational cost, referred to as the Morris method, was chosen to assess the relative effects of all parameters on the model’s outputs and to gain insights into predator–prey systems. Structure and results of the sensitivity analysis of the Sumatran tiger model – the Panthera Population Persistence (PPP) and the Notonecta foraging model (NFM) – were compared. Both models are based on a general predation cycle and designed to understand the mechanisms behind the predator–prey interaction being considered. However, the models differ significantly in their complexity and the details of the processes involved. In the sensitivity analysis, parameters that directly contribute to the number of prey items killed were found to be most influential. These were the growth rate of prey and the hunting radius of tigers in the PPP model as well as attack rate parameters and encounter distance of backswimmers in the NFM model. Analysis of distances in both of the models revealed further similarities in the sensitivity of the two individual-based models. The findings highlight the applicability and importance of sensitivity analyses in general, and screening design methods in particular, during early development of ecological individual-based models. Comparison of model structures and sensitivity analyses provides a first step for the derivation of general rules in the design of predator–prey models for both practical conservation and conceptual understanding. - Highlights: ► Structure of predation processes is similar in tiger and backswimmer model. ► The two individual-based models (IBM) differ in space formulations. ► In both models foraging distance is among the sensitive parameters. ► Morris method is applicable for the sensitivity analysis even of complex IBMs.

Probabilistic sensitivity analysis of optimised preventive maintenance strategies for deteriorating infrastructure assets

International Nuclear Information System (INIS)

Daneshkhah, A.; Stocks, N.G.; Jeffrey, P.

2017-01-01

Efficient life-cycle management of civil infrastructure systems under continuous deterioration can be improved by studying the sensitivity of optimised preventive maintenance decisions with respect to changes in model parameters. Sensitivity analysis in maintenance optimisation problems is important because if the calculation of the cost of preventive maintenance strategies is not sufficiently robust, the use of the maintenance model can generate optimised maintenances strategies that are not cost-effective. Probabilistic sensitivity analysis methods (particularly variance based ones), only partially respond to this issue and their use is limited to evaluating the extent to which uncertainty in each input contributes to the overall output's variance. These methods do not take account of the decision-making problem in a straightforward manner. To address this issue, we use the concept of the Expected Value of Perfect Information (EVPI) to perform decision-informed sensitivity analysis: to identify the key parameters of the problem and quantify the value of learning about certain aspects of the life-cycle management of civil infrastructure system. This approach allows us to quantify the benefits of the maintenance strategies in terms of expected costs and in the light of accumulated information about the model parameters and aspects of the system, such as the ageing process. We use a Gamma process model to represent the uncertainty associated with asset deterioration, illustrating the use of EVPI to perform sensitivity analysis on the optimisation problem for age-based and condition-based preventive maintenance strategies. The evaluation of EVPI indices is computationally demanding and Markov Chain Monte Carlo techniques would not be helpful. To overcome this computational difficulty, we approximate the EVPI indices using Gaussian process emulators. The implications of the worked numerical examples discussed in the context of analytical efficiency and organisational

A cost analysis of Colorado's 1991-92 oxygenated fuels program

International Nuclear Information System (INIS)

Manderino, L.A.; Bowles, S.L.

1993-01-01

This paper discusses the methodology used to conduct a cost analysis of Colorado's 1991-92 Oxygenated Fuels Program. This program requires the use of oxygenated fuels during the winter season in Denver and surrounding areas. The cost analysis was conducted as part of an overall cost-effectiveness study of the 1991-92 program conducted by PRC Environmental Management, Inc. (PRC). The paper, however, focuses on cost analysis and does not consider potential benefits of the program. The study analyzed costs incurred by different segments of society, including government, industry, and consumers. Because the analysis focused on a specific program year, neither past nor future costs were studied. The discussion of government costs includes the agencies interviewed and the types of costs associated with government administration and enforcement of the program. The methodology used to calculate costs to private industry is also present. The study examined the costs to fuel refineries, pipelines, and blenders, as well as fuel retailers and automobile fleet operators. Finally, the paper discusses the potential costs incurred by the consumer purchasing oxygenated fuels. Costs associated with issues such as vehicle driveability, automobile parts durability and performance, and fuel economy are also examined. A summary of all costs by category is presented along with an analysis of the major cost components. These include costs which are sensitive to specific circumstances and which may vary among programs

Societal costs in displaced transverse olecranon fractures: using decision analysis tools to find the most cost-effective strategy between tension band wiring and locked plating.

Science.gov (United States)

Francis, Tittu; Washington, Travis; Srivastava, Karan; Moutzouros, Vasilios; Makhni, Eric C; Hakeos, William

2017-11-01

Tension band wiring (TBW) and locked plating are common treatment options for Mayo IIA olecranon fractures. Clinical trials have shown excellent functional outcomes with both techniques. Although TBW implants are significantly less expensive than a locked olecranon plate, TBW often requires an additional operation for implant removal. To choose the most cost-effective treatment strategy, surgeons must understand how implant costs and return to the operating room influence the most cost-effective strategy. This cost-effective analysis study explored the optimal treatment strategies by using decision analysis tools. An expected-value decision tree was constructed to estimate costs based on the 2 implant choices. Values for critical variables, such as implant removal rate, were obtained from the literature. A Monte Carlo simulation consisting of 100,000 trials was used to incorporate variability in medical costs and implant removal rates. Sensitivity analysis and strategy tables were used to show how different variables influence the most cost-effective strategy. TBW was the most cost-effective strategy, with a cost savings of approximately $1300. TBW was also the dominant strategy by being the most cost-effective solution in 63% of the Monte Carlo trials. Sensitivity analysis identified implant costs for plate fixation and surgical costs for implant removal as the most sensitive parameters influencing the cost-effective strategy. Strategy tables showed the most cost-effective solution as 2 parameters vary simultaneously. TBW is the most cost-effective strategy in treating Mayo IIA olecranon fractures despite a higher rate of return to the operating room. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Sensitivity analysis of physiochemical interaction model: which pair ...

African Journals Online (AJOL)

... of two model parameters at a time on the solution trajectory of physiochemical interaction over a time interval. Our aim is to use this powerful mathematical technique to select the important pair of parameters of this physical process which is cost-effective. Keywords: Passivation Rate, Sensitivity Analysis, ODE23, ODE45 ...

CONSTRUCTION OF A DIFFERENTIAL ISOTHERMAL CALORIMETER OF HIGH SENSITIVITY AND LOW COST.

OpenAIRE

Trinca, RB; Perles, CE; Volpe, PLO

2009-01-01

CONSTRUCTION OF A DIFFERENTIAL ISOTHERMAL CALORIMETER OF HIGH SENSITIVITY AND LOW COST The high cost of sensitivity commercial calorimeters may represent an obstacle for many calorimetric research groups. This work describes (fie construction and calibration of a batch differential heat conduction calorimeter with sample cells volumes of about 400 mu L. The calorimeter was built using two small high sensibility square Peltier thermoelectric sensors and the total cost was estimated to be about...

Cost Attributable to Nosocomial Bacteremia. Analysis According to Microorganism and Antimicrobial Sensitivity in a University Hospital in Barcelona.

Directory of Open Access Journals (Sweden)

Marta Riu

Full Text Available To calculate the incremental cost of nosocomial bacteremia caused by the most common organisms, classified by their antimicrobial susceptibility.We selected patients who developed nosocomial bacteremia caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa. These microorganisms were analyzed because of their high prevalence and they frequently present multidrug resistance. A control group consisted of patients classified within the same all-patient refined-diagnosis related group without bacteremia. Our hospital has an established cost accounting system (full-costing that uses activity-based criteria to analyze cost distribution. A logistic regression model was fitted to estimate the probability of developing bacteremia for each admission (propensity score and was used for propensity score matching adjustment. Subsequently, the propensity score was included in an econometric model to adjust the incremental cost of patients who developed bacteremia, as well as differences in this cost, depending on whether the microorganism was multidrug-resistant or multidrug-sensitive.A total of 571 admissions with bacteremia matched the inclusion criteria and 82,022 were included in the control group. The mean cost was € 25,891 for admissions with bacteremia and € 6,750 for those without bacteremia. The mean incremental cost was estimated at € 15,151 (CI, € 11,570 to € 18,733. Multidrug-resistant P. aeruginosa bacteremia had the highest mean incremental cost, € 44,709 (CI, € 34,559 to € 54,859. Antimicrobial-susceptible E. coli nosocomial bacteremia had the lowest mean incremental cost, € 10,481 (CI, € 8,752 to € 12,210. Despite their lower cost, episodes of antimicrobial-susceptible E. coli nosocomial bacteremia had a major impact due to their high frequency.Adjustment of hospital cost according to the organism causing bacteremia and antibiotic sensitivity could improve prevention strategies

Failure Bounding And Sensitivity Analysis Applied To Monte Carlo Entry, Descent, And Landing Simulations

Science.gov (United States)

Gaebler, John A.; Tolson, Robert H.

2010-01-01

In the study of entry, descent, and landing, Monte Carlo sampling methods are often employed to study the uncertainty in the designed trajectory. The large number of uncertain inputs and outputs, coupled with complicated non-linear models, can make interpretation of the results difficult. Three methods that provide statistical insights are applied to an entry, descent, and landing simulation. The advantages and disadvantages of each method are discussed in terms of the insights gained versus the computational cost. The first method investigated was failure domain bounding which aims to reduce the computational cost of assessing the failure probability. Next a variance-based sensitivity analysis was studied for the ability to identify which input variable uncertainty has the greatest impact on the uncertainty of an output. Finally, probabilistic sensitivity analysis is used to calculate certain sensitivities at a reduced computational cost. These methods produce valuable information that identifies critical mission parameters and needs for new technology, but generally at a significant computational cost.

Cost Analysis of Treating Neonatal Hypoglycemia with Dextrose Gel.

Science.gov (United States)

Glasgow, Matthew J; Harding, Jane E; Edlin, Richard

2018-04-03

To evaluate the costs of using dextrose gel as a primary treatment for neonatal hypoglycemia in the first 48 hours after birth compared with standard care. We used a decision tree to model overall costs, including those specific to hypoglycemia monitoring and treatment and those related to the infant's length of stay in the postnatal ward or neonatal intensive care unit, comparing the use of dextrose gel for treatment of neonatal hypoglycemia with placebo, using data from the Sugar Babies randomized trial. Sensitivity analyses assessed the impact of dextrose gel cost, neonatal intensive care cost, cesarean delivery rate, and costs of glucose monitoring. In the primary analysis, treating neonatal hypoglycemia using dextrose gel had an overall cost of NZ$6863.81 and standard care (placebo) cost NZ$8178.25; a saving of NZ$1314.44 per infant treated. Sensitivity analyses showed that dextrose gel remained cost saving with wide variations in dextrose gel costs, neonatal intensive care unit costs, cesarean delivery rates, and costs of monitoring. Use of buccal dextrose gel reduces hospital costs for management of neonatal hypoglycemia. Because it is also noninvasive, well tolerated, safe, and associated with improved breastfeeding, buccal dextrose gel should be routinely used for initial treatment of neonatal hypoglycemia. Australian New Zealand Clinical Trials Registry: ACTRN12608000623392. Copyright © 2018 Elsevier Inc. All rights reserved.

Personalization of models with many model parameters: an efficient sensitivity analysis approach.

Science.gov (United States)

Donders, W P; Huberts, W; van de Vosse, F N; Delhaas, T

2015-10-01

Uncertainty quantification and global sensitivity analysis are indispensable for patient-specific applications of models that enhance diagnosis or aid decision-making. Variance-based sensitivity analysis methods, which apportion each fraction of the output uncertainty (variance) to the effects of individual input parameters or their interactions, are considered the gold standard. The variance portions are called the Sobol sensitivity indices and can be estimated by a Monte Carlo (MC) approach (e.g., Saltelli's method [1]) or by employing a metamodel (e.g., the (generalized) polynomial chaos expansion (gPCE) [2, 3]). All these methods require a large number of model evaluations when estimating the Sobol sensitivity indices for models with many parameters [4]. To reduce the computational cost, we introduce a two-step approach. In the first step, a subset of important parameters is identified for each output of interest using the screening method of Morris [5]. In the second step, a quantitative variance-based sensitivity analysis is performed using gPCE. Efficient sampling strategies are introduced to minimize the number of model runs required to obtain the sensitivity indices for models considering multiple outputs. The approach is tested using a model that was developed for predicting post-operative flows after creation of a vascular access for renal failure patients. We compare the sensitivity indices obtained with the novel two-step approach with those obtained from a reference analysis that applies Saltelli's MC method. The two-step approach was found to yield accurate estimates of the sensitivity indices at two orders of magnitude lower computational cost. Copyright © 2015 John Wiley & Sons, Ltd.

Cost analysis guidelines

International Nuclear Information System (INIS)

Strait, R.S.

1996-01-01

The first phase of the Depleted Uranium Hexafluoride Management Program (Program)--management strategy selection--consists of several program elements: Technology Assessment, Engineering Analysis, Cost Analysis, and preparation of an Environmental Impact Statement (EIS). Cost Analysis will estimate the life-cycle costs associated with each of the long-term management strategy alternatives for depleted uranium hexafluoride (UF6). The scope of Cost Analysis will include all major expenditures, from the planning and design stages through decontamination and decommissioning. The costs will be estimated at a scoping or preconceptual design level and are intended to assist decision makers in comparing alternatives for further consideration. They will not be absolute costs or bid-document costs. The purpose of the Cost Analysis Guidelines is to establish a consistent approach to analyzing of cost alternatives for managing Department of Energy's (DOE's) stocks of depleted uranium hexafluoride (DUF6). The component modules that make up the DUF6 management program differ substantially in operational maintenance, process-options, requirements for R and D, equipment, facilities, regulatory compliance, (O and M), and operations risk. To facilitate a consistent and equitable comparison of costs, the guidelines offer common definitions, assumptions or basis, and limitations integrated with a standard approach to the analysis. Further, the goal is to evaluate total net life-cycle costs and display them in a way that gives DOE the capability to evaluate a variety of overall DUF6 management strategies, including commercial potential. The cost estimates reflect the preconceptual level of the designs. They will be appropriate for distinguishing among management strategies

Design tradeoff studies and sensitivity analysis. Appendix B

Energy Technology Data Exchange (ETDEWEB)

1979-05-25

The results of the design trade-off studies and the sensitivity analysis of Phase I of the Near Term Hybrid Vehicle (NTHV) Program are presented. The effects of variations in the design of the vehicle body, propulsion systems, and other components on vehicle power, weight, cost, and fuel economy and an optimized hybrid vehicle design are discussed. (LCL)

Flat plate vs. concentrator solar photovoltaic cells - A manufacturing cost analysis

Science.gov (United States)

Granon, L. A.; Coleman, M. G.

1980-01-01

The choice of which photovoltaic system (flat plate or concentrator) to use for utilizing solar cells to generate electricity depends mainly on the cost. A detailed, comparative manufacturing cost analysis of the two types of systems is presented. Several common assumptions, i.e., cell thickness, interest rate, power rate, factory production life, polysilicon cost, and direct labor rate are utilized in this analysis. Process sequences, cost variables, and sensitivity analyses have been studied, and results of the latter show that the most important parameters which determine manufacturing costs are concentration ratio, manufacturing volume, and cell efficiency. The total cost per watt of the flat plate solar cell is $1.45, and that of the concentrator solar cell is $1.85, the higher cost being due to the increased process complexity and material costs.

Proposals for software analysis of cost effectiveness and cost-benefit for optimisation of radiation protection

International Nuclear Information System (INIS)

Schieber, C.; Lombard, J.; Lefaure, C.

1990-06-01

The objective of this report is to present the principles of decision making software for radiation protection option, applying ALARA principle. The choice of optimum options is performed by applying the models of cost effectiveness and cost-benefit. Options of radiation protection are described by two indicators: a simple economic indicator: cost of radiation protection; and dosimetry indicator: collective dose related to protection. For both analyses the software enables sensitivity analysis. It would be possible to complete the software by integrating a module which would take into account combinations of two options since they are not independent

Cost-sensitive case-based reasoning using a genetic algorithm: application to medical diagnosis.

Science.gov (United States)

Park, Yoon-Joo; Chun, Se-Hak; Kim, Byung-Chun

2011-02-01

The paper studies the new learning technique called cost-sensitive case-based reasoning (CSCBR) incorporating unequal misclassification cost into CBR model. Conventional CBR is now considered as a suitable technique for diagnosis, prognosis and prescription in medicine. However it lacks the ability to reflect asymmetric misclassification and often assumes that the cost of a positive diagnosis (an illness) as a negative one (no illness) is the same with that of the opposite situation. Thus, the objective of this research is to overcome the limitation of conventional CBR and encourage applying CBR to many real world medical cases associated with costs of asymmetric misclassification errors. The main idea involves adjusting the optimal cut-off classification point for classifying the absence or presence of diseases and the cut-off distance point for selecting optimal neighbors within search spaces based on similarity distribution. These steps are dynamically adapted to new target cases using a genetic algorithm. We apply this proposed method to five real medical datasets and compare the results with two other cost-sensitive learning methods-C5.0 and CART. Our finding shows that the total misclassification cost of CSCBR is lower than other cost-sensitive methods in many cases. Even though the genetic algorithm has limitations in terms of unstable results and over-fitting training data, CSCBR results with GA are better overall than those of other methods. Also the paired t-test results indicate that the total misclassification cost of CSCBR is significantly less than C5.0 and CART for several datasets. We have proposed a new CBR method called cost-sensitive case-based reasoning (CSCBR) that can incorporate unequal misclassification costs into CBR and optimize the number of neighbors dynamically using a genetic algorithm. It is meaningful not only for introducing the concept of cost-sensitive learning to CBR, but also for encouraging the use of CBR in the medical area

Cost-Effectiveness Analysis of Second-Line Chemotherapy Agents for Advanced Gastric Cancer.

Science.gov (United States)

Lam, Simon W; Wai, Maya; Lau, Jessica E; McNamara, Michael; Earl, Marc; Udeh, Belinda

2017-01-01

Gastric cancer is the fifth most common malignancy and second leading cause of cancer-related mortality. Chemotherapy options for patients who fail first-line treatment are limited. Thus the objective of this study was to assess the cost-effectiveness of second-line treatment options for patients with advanced or metastatic gastric cancer. Cost-effectiveness analysis using a Markov model to compare the cost-effectiveness of six possible second-line treatment options for patients with advanced gastric cancer who have failed previous chemotherapy: irinotecan, docetaxel, paclitaxel, ramucirumab, paclitaxel plus ramucirumab, and palliative care. The model was performed from a third-party payer's perspective to compare lifetime costs and health benefits associated with studied second-line therapies. Costs included only relevant direct medical costs. The model assumed chemotherapy cycle lengths of 30 days and a maximum number of 24 cycles. Systematic review of literature was performed to identify clinical data sources and utility and cost data. Quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) were calculated. The primary outcome measure for this analysis was the ICER between different therapies, where the incremental cost was divided by the number of QALYs saved. The ICER was compared with a willingness-to-pay (WTP) threshold that was set at $50,000/QALY gained, and an exploratory analysis using $160,000/QALY gained was also used. The model's robustness was tested by using 1-way sensitivity analyses and a 10,000 Monte Carlo simulation probabilistic sensitivity analysis (PSA). Irinotecan had the lowest lifetime cost and was associated with a QALY gain of 0.35 year. Docetaxel, ramucirumab alone, and palliative care were dominated strategies. Paclitaxel and the combination of paclitaxel plus ramucirumab led to higher QALYs gained, at an incremental cost of $86,815 and $1,056,125 per QALY gained, respectively. Based on our prespecified

Cost-Effectiveness Analysis of Diagnosis of Duchenne/Becker Muscular Dystrophy in Colombia.

Science.gov (United States)

Atehortúa, Sara C; Lugo, Luz H; Ceballos, Mateo; Orozco, Esteban; Castro, Paula A; Arango, Juan C; Mateus, Heidi E

2018-03-09

To determine the cost-effectiveness ratio of different courses of action for the diagnosis of Duchenne or Becker muscular dystrophy in Colombia. The cost-effectiveness analysis was performed from the Colombian health system perspective. Decision trees were constructed, and different courses of action were compared considering the following tests: immunohistochemistry (IHC), Western blot (WB), multiplex polymerase chain reaction, multiplex ligation-dependent probe amplification (MLPA), and the complete sequencing of the dystrophin gene. The time horizon matched the duration of sample extraction and analysis. Transition probabilities were obtained from a systematic review. Costs were constructed with a type-case methodology using the consensus of experts and the valuation of resources from consulting laboratories and the 2001 Social Security Institute cost manual. Deterministic sensitivity and scenario analyses were performed with one or more unavailable alternatives. Costs were converted from Colombian pesos to US dollars using the 2014 exchange rate. In the base case, WB was the dominant strategy, with a cost of US $419.07 and a sensitivity of 100%. This approach remains the dominant strategy down to a 98.2% sensitivity and while costs do not exceed US $837.38. If WB was not available, IHC had the best cost-effectiveness ratio, followed by MLPA and sequencing. WB is a cost-effective alternative for the diagnosis of patients suspected of having Duchenne or Becker muscular dystrophy in the Colombian health system. The IHC test is rated as the second-best detection method. If these tests are not available, MLPA followed by sequencing would be the most cost-effective alternative. Copyright © 2018. Published by Elsevier Inc.

Complete daVinci versus laparoscopic pyeloplasty: cost analysis.

Science.gov (United States)

Bhayani, Sam B; Link, Richard E; Varkarakis, John M; Kavoussi, Louis R

2005-04-01

Computer-assisted pyeloplasty with the daVinci system is an emerging technique to treat ureteropelvic junction (UPJ) obstruction. A relative cost analysis was performed assessing this technology in comparison with purely laparoscopic pyeloplasty. Eight patients underwent computer-assisted (daVinci) dismembered pyeloplasty (CP) via a transperitoneal four-port approach. They were compared with 13 patients who underwent purely laparoscopic pyeloplasty (LP). All patients had a primary UPJ obstruction and were matched for age, sex, and body mass index. The cost of equipment and capital depreciation for both procedures, as well as assessment of room set-up time, takedown time, and personnel were analyzed. Surgeons and nursing staff for both groups were experienced in both laparoscopy and daVinci procedures. One- and two-way financial analysis was performed to assess relative costs. The mean set-up and takedown time was 71 minutes for CP and 49 minutes for LP. The mean length of stay was 2.3 days for CP and 2.5 days for LP. The mean operating room (OR) times for CP and LP were 176 and 210 minutes, respectively. There were no complications in either group. One-way cost analysis with an economic model showed that LP is more cost effective than CP at our hospital if LP OR time is cost effective as LP. Two-way sensitivity analysis shows that in-room time must still be 500 to obtain cost equivalence for CP. Perioperative parameters for CP are encouraging. However, the costs are a clear disadvantage. In our hospital, it is more cost effective to teach and perform LP than to perform CP.

Low Cost, Low Power, High Sensitivity Magnetometer

Science.gov (United States)

2008-12-01

which are used to measure the small magnetic signals from brain. Other types of vector magnetometers are fluxgate , coil based, and magnetoresistance...concentrator with the magnetometer currently used in Army multimodal sensor systems, the Brown fluxgate . One sees the MEMS fluxgate magnetometer is...Guedes, A.; et al., 2008: Hybrid - LOW COST, LOW POWER, HIGH SENSITIVITY MAGNETOMETER A.S. Edelstein*, James E. Burnette, Greg A. Fischer, M.G

Soft-copy sonography: cost reduction sensitivity analysis in a pediatric hospital.

Science.gov (United States)

Don, S; Albertina, M J; Ammann, D

1998-03-01

Our objective was to determine whether interpreting sonograms of pediatric patients using soft-copy (computer workstation) instead of laser-printed film could reduce costs for a pediatric radiology department. We used theoretic models of growth to analyze costs. The costs of a sonographic picture archiving and communication system (three interface devices, two workstations, a network server, maintenance expenses, and storage media costs) were compared with the potential savings of eliminating film and increasing technologist efficiency or reducing the number of technologists. The model was based on historic trends and future capitation estimates that will reduce fee-for-service reimbursement. The effects of varying the study volume and reducing technologists' work hours were analyzed. By converting to soft-copy interpretation, we saved 6 min 32 sec per examination by eliminating film processing waiting time, thus reducing examination time from 30 min to 24 min. During an average day of 27 examinations, 176 min were saved. However, 33 min a day were spent retrieving prior studies from long-term storage; thus, 143 extra minutes a day were available for scanning. This improved efficiency could result in five more sonograms a day obtained by converting to soft-copy interpretation, using existing staff and equipment. Alternatively, five examinations a day would equate to one half of a full-time equivalent technologists position. Our analysis of costs considered that the hospital's anticipated growth of sonography and the depreciation of equipment during 5 years resulted in a savings of more than $606,000. Increasing the examinations by just 200 sonograms in the first year and no further growth resulted in a savings of more than $96,000. If the number of sonograms stayed constant, elimination of film printing alone resulted in a loss of approximately $157,000; reduction of one half of a full-time equivalent technologist's position would recuperate approximately $134

Improving the quality of pressure ulcer care with prevention: a cost-effectiveness analysis.

Science.gov (United States)

Padula, William V; Mishra, Manish K; Makic, Mary Beth F; Sullivan, Patrick W

2011-04-01

In October 2008, Centers for Medicare and Medicaid Services discontinued reimbursement for hospital-acquired pressure ulcers (HAPUs), thus placing stress on hospitals to prevent incidence of this costly condition. To evaluate whether prevention methods are cost-effective compared with standard care in the management of HAPUs. A semi-Markov model simulated the admission of patients to an acute care hospital from the time of admission through 1 year using the societal perspective. The model simulated health states that could potentially lead to an HAPU through either the practice of "prevention" or "standard care." Univariate sensitivity analyses, threshold analyses, and Bayesian multivariate probabilistic sensitivity analysis using 10,000 Monte Carlo simulations were conducted. Cost per quality-adjusted life-years (QALYs) gained for the prevention of HAPUs. Prevention was cost saving and resulted in greater expected effectiveness compared with the standard care approach per hospitalization. The expected cost of prevention was $7276.35, and the expected effectiveness was 11.241 QALYs. The expected cost for standard care was $10,053.95, and the expected effectiveness was 9.342 QALYs. The multivariate probabilistic sensitivity analysis showed that prevention resulted in cost savings in 99.99% of the simulations. The threshold cost of prevention was $821.53 per day per person, whereas the cost of prevention was estimated to be $54.66 per day per person. This study suggests that it is more cost effective to pay for prevention of HAPUs compared with standard care. Continuous preventive care of HAPUs in acutely ill patients could potentially reduce incidence and prevalence, as well as lead to lower expenditures.

Sensitivity and uncertainty analysis

CERN Document Server

Cacuci, Dan G; Navon, Ionel Michael

2005-01-01

As computer-assisted modeling and analysis of physical processes have continued to grow and diversify, sensitivity and uncertainty analyses have become indispensable scientific tools. Sensitivity and Uncertainty Analysis. Volume I: Theory focused on the mathematical underpinnings of two important methods for such analyses: the Adjoint Sensitivity Analysis Procedure and the Global Adjoint Sensitivity Analysis Procedure. This volume concentrates on the practical aspects of performing these analyses for large-scale systems. The applications addressed include two-phase flow problems, a radiative c

Cost-effectiveness analysis of radon remediation in schools

International Nuclear Information System (INIS)

Kennedy, C.A.; Gray, A.M.

2000-01-01

sensitivity analysis show that the ratio is particularly sensitive to assumptions of two parameters including: the average capital cost of remediation and the discount rates chosen for the life yells. The overall model presented in this study can be applied to any other area, and alternative regional parameter estimates can be substituted if these are available. As the sensitivity analysis shows, however, remediation is likely to prove cost-effective even if these parameter estimates are substantially different. These results should help to inform further discussion of policy setting for radon remediation in various settings. It provides an empirical example of the type of economic analysis encouraged by both the UK NRPB (1986) and the ICRP (1983). General information on the average costs of remediation and potential savings to the health care system will be helpful as increasing numbers of local authorities start planning remediation programmes for the schools under their care. This study also highlights the need for the evaluation of other schools remediation-based radon-induced lung cancer prevention programmes in other countries using similar methodological techniques. (author)

A cost-benefit analysis of The National Map

Science.gov (United States)

Halsing, David L.; Theissen, Kevin; Bernknopf, Richard

2003-01-01

, over its 30-year projected lifespan, The National Map will bring a net present value (NPV) of benefits of $2.05 billion in 2001 dollars. The average time until the initial investments (the break-even period) are recovered is 14 years. Table ES-1 shows a running total of NPV in each year of the simulation model. In year 14, The National Map first shows a positive NPV, and so the table is highlighted in gray after that point. Figure ES-1 is a graph of the total benefit and total cost curves of a single model run over time. The curves cross in year 14, when the project breaks even. A sensitivity analysis of the input variables illustrated that these results of the NPV of The National Map are quite robust. Figure ES-2 plots the mean NPV results from 60 different scenarios, each consisting of fifty 30-year runs. The error bars represent a two-standard-deviation range around each mean. The analysis that follows contains the details of the cost-benefit analysis, the framework for evaluating economic benefits, a computational simulation tool, and a sensitivity analysis of model variables and values.

On the role of cost-sensitive learning in multi-class brain-computer interfaces.

Science.gov (United States)

Devlaminck, Dieter; Waegeman, Willem; Wyns, Bart; Otte, Georges; Santens, Patrick

2010-06-01

Brain-computer interfaces (BCIs) present an alternative way of communication for people with severe disabilities. One of the shortcomings in current BCI systems, recently put forward in the fourth BCI competition, is the asynchronous detection of motor imagery versus resting state. We investigated this extension to the three-class case, in which the resting state is considered virtually lying between two motor classes, resulting in a large penalty when one motor task is misclassified into the other motor class. We particularly focus on the behavior of different machine-learning techniques and on the role of multi-class cost-sensitive learning in such a context. To this end, four different kernel methods are empirically compared, namely pairwise multi-class support vector machines (SVMs), two cost-sensitive multi-class SVMs and kernel-based ordinal regression. The experimental results illustrate that ordinal regression performs better than the other three approaches when a cost-sensitive performance measure such as the mean-squared error is considered. By contrast, multi-class cost-sensitive learning enables us to control the number of large errors made between two motor tasks.

A cost analysis of implementing a behavioral weight loss intervention in community mental health settings: Results from the ACHIEVE trial.

Science.gov (United States)

Janssen, Ellen M; Jerome, Gerald J; Dalcin, Arlene T; Gennusa, Joseph V; Goldsholl, Stacy; Frick, Kevin D; Wang, Nae-Yuh; Appel, Lawrence J; Daumit, Gail L

2017-06-01

In the ACHIEVE randomized controlled trial, an 18-month behavioral intervention accomplished weight loss in persons with serious mental illness who attended community psychiatric rehabilitation programs. This analysis estimates costs for delivering the intervention during the study. It also estimates expected costs to implement the intervention more widely in a range of community mental health programs. Using empirical data, costs were calculated from the perspective of a community psychiatric rehabilitation program delivering the intervention. Personnel and travel costs were calculated using time sheet data. Rent and supply costs were calculated using rent per square foot and intervention records. A univariate sensitivity analysis and an expert-informed sensitivity analysis were conducted. With 144 participants receiving the intervention and a mean weight loss of 3.4 kg, costs of $95 per participant per month and $501 per kilogram lost in the trial were calculated. In univariate sensitivity analysis, costs ranged from $402 to $725 per kilogram lost. Through expert-informed sensitivity analysis, it was estimated that rehabilitation programs could implement the intervention for $68 to $85 per client per month. Costs of implementing the ACHIEVE intervention were in the range of other intensive behavioral weight loss interventions. Wider implementation of efficacious lifestyle interventions in community mental health settings will require adequate funding mechanisms. © 2017 The Obesity Society.

Cost analysis of open radical cystectomy versus robot-assisted radical cystectomy.

Science.gov (United States)

Bansal, Sukhchain S; Dogra, Tara; Smith, Peter W; Amran, Maisarah; Auluck, Ishna; Bhambra, Maninder; Sura, Manraj S; Rowe, Edward; Koupparis, Anthony

2018-03-01

To perform a cost analysis comparing the cost of robot-assisted radical cystectomy (RARC) with open RC (ORC) in a UK tertiary referral centre and to identify the key cost drivers. Data on hospital length of stay (LOS), operative time (OT), transfusion rate, and volume and complication rate were obtained from a prospectively updated institutional database for patients undergoing RARC or ORC. A cost decision tree model was created. Sensitivity analysis was performed to find key drivers of overall cost and to find breakeven points with ORC. Monte Carlo analysis was performed to quantify the variability in the dataset. One RARC procedure costs £12 449.87, or £12 106.12 if the robot was donated via charitable funds. In comparison, one ORC procedure costs £10 474.54. RARC is 18.9% more expensive than ORC. The key cost drivers were OT, LOS, and the number of cases performed per annum. High ongoing equipment costs remain a large barrier to the cost of RARC falling. However, minimal improvements in patient quality of life would be required to offset this difference. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

Analysis of capital and operating costs associated with high level waste solidification processes

International Nuclear Information System (INIS)

Heckman, R.A.; Kniazewycz, B.G.

1978-03-01

An analysis was performed to evaluate the sensitivity of annual operating costs and capital costs of waste solidification processes to various parameters defined by the requirements of a proposed Federal waste repository. Five process methods and waste forms examined were: salt cake, spray calcine, fluidized bed calcine, borosilicate glass, and supercalcine multibarrier. Differential cost estimates of the annual operating and maintenance costs and the capital costs for the five HLW solidification alternates were developed

Sensitivity Analysis of features in tolerancing based on constraint function level sets

International Nuclear Information System (INIS)

Ziegler, Philipp; Wartzack, Sandro

2015-01-01

Usually, the geometry of the manufactured product inherently varies from the nominal geometry. This may negatively affect the product functions and properties (such as quality and reliability), as well as the assemblability of the single components. In order to avoid this, the geometric variation of these component surfaces and associated geometry elements (like hole axes) are restricted by tolerances. Since tighter tolerances lead to significant higher manufacturing costs, tolerances should be specified carefully. Therefore, the impact of deviating component surfaces on functions, properties and assemblability of the product has to be analyzed. As physical experiments are expensive, methods of statistical tolerance analysis tools are widely used in engineering design. Current tolerance simulation tools lack of an appropriate indicator for the impact of deviating component surfaces. In the adoption of Sensitivity Analysis methods, there are several challenges, which arise from the specific framework in tolerancing. This paper presents an approach to adopt Sensitivity Analysis methods on current tolerance simulations with an interface module, which bases on level sets of constraint functions for parameters of the simulation model. The paper is an extension and generalization of Ziegler and Wartzack [1]. Mathematical properties of the constraint functions (convexity, homogeneity), which are important for the computational costs of the Sensitivity Analysis, are shown. The practical use of the method is illustrated in a case study of a plain bearing. - Highlights: • Alternative definition of Deviation Domains. • Proof of mathematical properties of the Deviation Domains. • Definition of the interface between Deviation Domains and Sensitivity Analysis. • Sensitivity analysis of a gearbox to show the methods practical use

A Support for Decision Making: Cost-Sensitive Learning System

Czech Academy of Sciences Publication Activity Database

Brůha, I.; Kočková, Sylva

č. 6 (1994), s. 67-82 ISSN 0933-3657 R&D Projects: GA ČR GA201/93/0781 Keywords : learning algorithm * noisy environment * inductive algorithm * decision rule * cost-sensitive inference * evaluating function Impact factor: 0.672, year: 1994

Different Imaging Strategies in Patients With Possible Basilar Artery Occlusion: Cost-Effectiveness Analysis.

Science.gov (United States)

Beyer, Sebastian E; Hunink, Myriam G; Schöberl, Florian; von Baumgarten, Louisa; Petersen, Steffen E; Dichgans, Martin; Janssen, Hendrik; Ertl-Wagner, Birgit; Reiser, Maximilian F; Sommer, Wieland H

2015-07-01

This study evaluated the cost-effectiveness of different noninvasive imaging strategies in patients with possible basilar artery occlusion. A Markov decision analytic model was used to evaluate long-term outcomes resulting from strategies using computed tomographic angiography (CTA), magnetic resonance imaging, nonenhanced CT, or duplex ultrasound with intravenous (IV) thrombolysis being administered after positive findings. The analysis was performed from the societal perspective based on US recommendations. Input parameters were derived from the literature. Costs were obtained from United States costing sources and published literature. Outcomes were lifetime costs, quality-adjusted life-years (QALYs), incremental cost-effectiveness ratios, and net monetary benefits, with a willingness-to-pay threshold of $80,000 per QALY. The strategy with the highest net monetary benefit was considered the most cost-effective. Extensive deterministic and probabilistic sensitivity analyses were performed to explore the effect of varying parameter values. In the reference case analysis, CTA dominated all other imaging strategies. CTA yielded 0.02 QALYs more than magnetic resonance imaging and 0.04 QALYs more than duplex ultrasound followed by CTA. At a willingness-to-pay threshold of $80,000 per QALY, CTA yielded the highest net monetary benefits. The probability that CTA is cost-effective was 96% at a willingness-to-pay threshold of $80,000/QALY. Sensitivity analyses showed that duplex ultrasound was cost-effective only for a prior probability of ≤0.02 and that these results were only minimally influenced by duplex ultrasound sensitivity and specificity. Nonenhanced CT and magnetic resonance imaging never became the most cost-effective strategy. Our results suggest that CTA in patients with possible basilar artery occlusion is cost-effective. © 2015 The Authors.

Cost-minimization analysis of subcutaneous abatacept in the treatment of rheumatoid arthritis in Spain

Directory of Open Access Journals (Sweden)

R. Ariza

2014-07-01

Full Text Available Objective: To compare the cost of treating rheumatoid arthritis patients that have failed an initial treatment with methotrexate, with subcutaneous aba - tacept versus other first-line biologic disease-modifying antirheumatic drugs. Method: Subcutaneous abatacept was considered comparable to intravenous abatacept, adalimumab, certolizumab pegol, etanercept, golimumab, infliximab and tocilizumab, based on indirect comparison using mixed treatment analysis. A cost-minimization analysis was therefore considered appropriate. The Spanish Health System perspective and a 3 year time horizon were selected. Pharmaceutical and administration costs (, 2013 of all available first-line biological disease-modifying antirheumatic drugs were considered. Administration costs were obtained from a local costs database. Patients were considered to have a weight of 70 kg. A 3% annual discount rate was applied. Deterministic and probabilistic sensitivity analyses were performed. Results: Subcutaneous abatacept proved in the base case to be less costly than all other biologic antirrheumatic drugs (ranging from -831.42 to -9,741.69 versus infliximab and tocilizumab, respectively. Subcutaneous abatacept was associated with a cost of 10,760.41 per patient during the first year of treatment and 10,261.29 in subsequent years. The total 3-year cost of subcutaneous abatacept was 29,953.89 per patient. Sensitivity analyses proved the model to be robust. Subcutaneous abatacept remained cost-saving in 100% of probabilistic sensitivity analysis simulations versus adalimumab, certolizumab, etanercept and golimumab, in more than 99.6% versus intravenous abatacept and tocilizumab and in 62.3% versus infliximab. Conclusions: Treatment with subcutaneous abatacept is cost-saving versus intravenous abatacept, adalimumab, certolizumab, etanercept, golimumab, infliximab and tocilizumab in the management of rheumatoid arthritis patients initiating

Telemedicine in the management of chronic pain: a cost analysis study.

Science.gov (United States)

Pronovost, Antoine; Peng, Philip; Kern, Ralph

2009-08-01

Telemedicine provides patients with easy and remote access to consultant expertise irrespective of geographic location. In a randomized controlled trial, this study has applied a rigorous costing methodology to the use of telemedicine in chronic pain management. We performed a randomized two-period crossover trial comparing in-person (IP) consultation with telemedicine (TM) consultation in the management of chronic pain. Over an 18-month period, 26 patients each completed two diaries capturing their direct and indirect travel costs, daily pain scores, and satisfaction with physician consultation. Costing models were developed to account for direct, indirect, fixed, and variable costs in order to perform break-even analyses. Sensitivity analysis was performed over a broad range of assumptions. Direct patient costs were significantly lower in the TM group than in the IP group, with median cost and interquartile range 133 dollars (28-377) vs 443 dollars (292-1075), respectively (P = 0.001). More patients were highly satisfied with the TM consultation than with the IP consultation (56 and 24%, respectively; P sensitivity analysis controlling for annual patient volume and round-trip distance indicated that TM remains cost-effective at volumes >50 patients/year or at round-trip distances >200 km. Telemedicine is cost-effective over a broad range of assumptions, including annual patient volumes, travel distance, fuel costs, amortization, and discount rates. This study provides data from a real-world setting to determine relevant thresholds and targets for establishing a TM program for patients who are undergoing chronic pain therapy.

Evaluation of a Stratified National Breast Screening Program in the United Kingdom: An Early Model-Based Cost-Effectiveness Analysis.

Science.gov (United States)

Gray, Ewan; Donten, Anna; Karssemeijer, Nico; van Gils, Carla; Evans, D Gareth; Astley, Sue; Payne, Katherine

2017-09-01

To identify the incremental costs and consequences of stratified national breast screening programs (stratified NBSPs) and drivers of relative cost-effectiveness. A decision-analytic model (discrete event simulation) was conceptualized to represent four stratified NBSPs (risk 1, risk 2, masking [supplemental screening for women with higher breast density], and masking and risk 1) compared with the current UK NBSP and no screening. The model assumed a lifetime horizon, the health service perspective to identify costs (£, 2015), and measured consequences in quality-adjusted life-years (QALYs). Multiple data sources were used: systematic reviews of effectiveness and utility, published studies reporting costs, and cohort studies embedded in existing NBSPs. Model parameter uncertainty was assessed using probabilistic sensitivity analysis and one-way sensitivity analysis. The base-case analysis, supported by probabilistic sensitivity analysis, suggested that the risk stratified NBSPs (risk 1 and risk-2) were relatively cost-effective when compared with the current UK NBSP, with incremental cost-effectiveness ratios of £16,689 per QALY and £23,924 per QALY, respectively. Stratified NBSP including masking approaches (supplemental screening for women with higher breast density) was not a cost-effective alternative, with incremental cost-effectiveness ratios of £212,947 per QALY (masking) and £75,254 per QALY (risk 1 and masking). When compared with no screening, all stratified NBSPs could be considered cost-effective. Key drivers of cost-effectiveness were discount rate, natural history model parameters, mammographic sensitivity, and biopsy rates for recalled cases. A key assumption was that the risk model used in the stratification process was perfectly calibrated to the population. This early model-based cost-effectiveness analysis provides indicative evidence for decision makers to understand the key drivers of costs and QALYs for exemplar stratified NBSP. Copyright

Analysis of the total system life cycle cost for the Civilian Radioactive Waste Management Program. Volume 1. The analysis and its results

International Nuclear Information System (INIS)

1986-04-01

The total-system life-cycle cost (TSLCC) analysis for the Department of Energy's (DOE) Civilian Radioactive Waste Management Program is an ongoing activity that helps determine whether the revenue-producing mechanism established by the Nuclear Waste Policy Act of 1982 is sufficient to cover the cost of the program. This report provides cost estimates for the fourth evaluation of the adequacy of the fee. The total-system cost for the reference authorized-system program is estimated to be 24 to 32 billion (1985) dollars. The total-system cost for the reference improved-performance system is estimated to be 26 to 34 billion dollars. A number of sensitivity cases were analyzed. For the authorized system, the costs for the sensitivity cases studied range from 21 to 39 billion dollars. For the improved-performance system, which includes a facility for monitored retrievable storage, the total-system cost in the sensitivity cases is estimated to be as high as 41 billion dollars. The factors that affect costs more than any other single factor for both the authorized and the improved-performance systems are delays in repository startup. A preliminary analysis of the impact of extending the burnup of nuclear fuel in the reactor was also performed; its results indicate that the impact is insignificant: the total-system cost is essentially unchanged from the comparable constant-burnup cases. The current estimate of the the total-system cost for the reference authorized system is zero to 3 billion dollars (9%) higher than the estimate for the reference system in the January 1985 TSLCC analysis

WHAT IF (Sensitivity Analysis

Directory of Open Access Journals (Sweden)

Iulian N. BUJOREANU

2011-01-01

Full Text Available Sensitivity analysis represents such a well known and deeply analyzed subject that anyone to enter the field feels like not being able to add anything new. Still, there are so many facets to be taken into consideration.The paper introduces the reader to the various ways sensitivity analysis is implemented and the reasons for which it has to be implemented in most analyses in the decision making processes. Risk analysis is of outmost importance in dealing with resource allocation and is presented at the beginning of the paper as the initial cause to implement sensitivity analysis. Different views and approaches are added during the discussion about sensitivity analysis so that the reader develops an as thoroughly as possible opinion on the use and UTILITY of the sensitivity analysis. Finally, a round-up conclusion brings us to the question of the possibility of generating the future and analyzing it before it unfolds so that, when it happens it brings less uncertainty.

Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities

Energy Technology Data Exchange (ETDEWEB)

Denholm, P.; Margolis, R. M.; Ong, S.; Roberts, B.

2009-12-01

Grid parity--or break-even cost--for photovoltaic (PV) technology is defined as the point where the cost of PV-generated electricity equals the cost of electricity purchased from the grid. Break-even cost is expressed in $/W of an installed system. Achieving break-even cost is a function of many variables. Consequently, break-even costs vary by location and time for a country, such as the United States, with a diverse set of resources, electricity prices, and other variables. In this report, we analyze PV break-even costs for U.S. residential customers. We evaluate some key drivers of grid parity both regionally and over time. We also examine the impact of moving from flat to time-of-use (TOU) rates, and we evaluate individual components of the break-even cost, including effect of rate structure and various incentives. Finally, we examine how PV markets might evolve on a regional basis considering the sensitivity of the break-even cost to four major drivers: technical performance, financing parameters, electricity prices and rates, and policies. We find that local incentives rather than ?technical? parameters are in general the key drivers of the break-even cost of PV. Additionally, this analysis provides insight about the potential viability of PV markets.

Management of End-Stage Ankle Arthritis: Cost-Utility Analysis Using Direct and Indirect Costs.

Science.gov (United States)

Nwachukwu, Benedict U; McLawhorn, Alexander S; Simon, Matthew S; Hamid, Kamran S; Demetracopoulos, Constantine A; Deland, Jonathan T; Ellis, Scott J

2015-07-15

Total ankle replacement and ankle fusion are costly but clinically effective treatments for ankle arthritis. Prior cost-effectiveness analyses for the management of ankle arthritis have been limited by a lack of consideration of indirect costs and nonoperative management. The purpose of this study was to compare the cost-effectiveness of operative and nonoperative treatments for ankle arthritis with inclusion of direct and indirect costs in the analysis. Markov model analysis was conducted from a health-systems perspective with use of direct costs and from a societal perspective with use of direct and indirect costs. Costs were derived from the 2012 Nationwide Inpatient Sample (NIS) and expressed in 2013 U.S. dollars; effectiveness was expressed in quality-adjusted life years (QALYs). Model transition probabilities were derived from the available literature. The principal outcome measure was the incremental cost-effectiveness ratio (ICER). In the direct-cost analysis for the base case, total ankle replacement was associated with an ICER of $14,500/QALY compared with nonoperative management. When indirect costs were included, total ankle replacement was both more effective and resulted in $5900 and $800 in lifetime cost savings compared with the lifetime costs following nonoperative management and ankle fusion, respectively. At a $100,000/QALY threshold, surgical management of ankle arthritis was preferred for patients younger than ninety-six years and total ankle replacement was increasingly more cost-effective in younger patients. Total ankle replacement, ankle fusion, and nonoperative management were the preferred strategy in 83%, 12%, and 5% of the analyses, respectively; however, our model was sensitive to patient age, the direct costs of total ankle replacement, the failure rate of total ankle replacement, and the probability of arthritis after ankle fusion. Compared with nonoperative treatment for the management of end-stage ankle arthritis, total ankle

Deterministic sensitivity and uncertainty analysis for large-scale computer models

International Nuclear Information System (INIS)

Worley, B.A.; Pin, F.G.; Oblow, E.M.; Maerker, R.E.; Horwedel, J.E.; Wright, R.Q.

1988-01-01

The fields of sensitivity and uncertainty analysis have traditionally been dominated by statistical techniques when large-scale modeling codes are being analyzed. These methods are able to estimate sensitivities, generate response surfaces, and estimate response probability distributions given the input parameter probability distributions. Because the statistical methods are computationally costly, they are usually applied only to problems with relatively small parameter sets. Deterministic methods, on the other hand, are very efficient and can handle large data sets, but generally require simpler models because of the considerable programming effort required for their implementation. The first part of this paper reports on the development and availability of two systems, GRESS and ADGEN, that make use of computer calculus compilers to automate the implementation of deterministic sensitivity analysis capability into existing computer models. This automation removes the traditional limitation of deterministic sensitivity methods. This second part of the paper describes a deterministic uncertainty analysis method (DUA) that uses derivative information as a basis to propagate parameter probability distributions to obtain result probability distributions. This paper is applicable to low-level radioactive waste disposal system performance assessment

Parameter identification and global sensitivity analysis of Xin'anjiang model using meta-modeling approach

Directory of Open Access Journals (Sweden)

Xiao-meng Song

2013-01-01

Full Text Available Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on (1 a screening method (Morris for qualitative ranking of parameters, and (2 a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model (RSMSobol. First, the Morris screening method was used to qualitatively identify the parameters' sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model (RSM were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model.

Cost-effectiveness of Human Papilloma Virus (HPV) vaccination in Nigeria: a decision analysis using pragmatic parameter estimates for cost and programme coverage.

Science.gov (United States)

Ekwunife, Obinna I; Lhachimi, Stefan K

2017-12-08

World Health Organisation recommends routine Human Papilloma Virus (HPV) vaccination for girls when its cost-effectiveness in the country or region has been duly considered. We therefore aimed to evaluate cost-effectiveness of HPV vaccination in Nigeria using pragmatic parameter estimates for cost and programme coverage, i.e. realistically achievable in the studied context. A microsimulation frame-work was used. The natural history for cervical cancer disease was remodelled from a previous Nigerian model-based study. Costing was based on health providers' perspective. Disability adjusted life years attributable to cervical cancer mortality served as benefit estimate. Suitable policy option was obtained by calculating the incremental costs-effectiveness ratio. Probabilistic sensitivity analysis was used to assess parameter uncertainty. One-way sensitivity analysis was used to explore the robustness of the policy recommendation to key parameters alteration. Expected value of perfect information (EVPI) was calculated to determine the expected opportunity cost associated with choosing the optimal scenario or strategy at the maximum cost-effectiveness threshold. Combination of the current scenario of opportunistic screening and national HPV vaccination programme (CS + NV) was the only cost-effective and robust policy option. However, CS + NV scenario was only cost-effective so far the unit cost of HPV vaccine did not exceed $5. EVPI analysis showed that it may be worthwhile to conduct additional research to inform the decision to adopt CS + NV. National HPV vaccination combined with opportunist cervical cancer screening is cost-effective in Nigeria. However, adoption of this strategy should depend on its relative efficiency when compared to other competing new vaccines and health interventions.

Sensitivity Analysis of Multi-objective Optimization for Solid Waste Management: A Case Study of Dar es Salaam, Tanzania

Directory of Open Access Journals (Sweden)

Halidi Lyeme

2017-11-01

Full Text Available In this study, a sensitivity analysis of a multi-objective optimization model for solid waste management (SWM for Dar es Salaam city in Tanzania is considered. Our objectives were to identify the most sensitive parameters and effect of other input data to the model output. Five scenarios were considered by varying their associated parameter values. The results showed that the decrease of total cost for the SWM system in all scenarios was observed compared to the baseline solution when the single landfill was considered. Furthermore, the analysis shows that the variable cost parameter for the processing facilities is very sensitivity in such a way that if you increase the variable cost then, there is a rapid increase of total cost for the SWM system and the vice versa is true. The relevant suggestions to the decision makers were also discussed.

Cost-effectiveness analysis of the introduction of rotavirus vaccine in Iran.

Science.gov (United States)

Javanbakht, Mehdi; Moradi-Lakeh, Maziar; Yaghoubi, Mohsen; Esteghamati, Abdoulreza; Mansour Ghanaie, Roxana; Mahmoudi, Sussan; Shamshiri, Ahmad-Reza; Zahraei, Seyed Mohsen; Baxter, Louise; Shakerian, Sareh; Chaudhri, Irtaza; Fleming, Jessica A; Munier, Aline; Baradaran, Hamid R

2015-05-07

Although the mortality from diarrheal diseases has been decreasing dramatically in Iran, it still represents an important proportion of disease burden in children Rotavirus vaccines are among the most effective strategies against diarrheal diseases in specific epidemiological conditions. This study aimed to evaluate the cost-effectiveness of the introduction of rotavirus vaccine (3 doses of pentavalent RotaTeq (RV5)) in Iran, from the viewpoints of Iran's health system and society. The TRIVAC decision support model was used to calculate total incremental costs, life years (LYs) gained, and disability-adjusted life years (DALYs) averted due to the vaccination program. Necessary input data were collected from the most valid accessible sources as well as a systematic review and meta-analysis on epidemiological studies. We used WHO guidelines to estimate vaccination cost. An annual discount rate of 3% was considered for both health gain and costs. A deterministic sensitivity analysis was performed for testing the robustness of the models results. Our results indicated that total DALYs potentially lost due to rotavirus diarrhea within 10 years would be 138,161, of which 76,591 could be prevented by rotavirus vaccine. The total vaccination cost for 10 cohorts was estimated to be US$ 499.91 million. Also, US$ 470.61 million would be saved because of preventing outpatient visits and inpatient admissions (cost-saving from the society perspective). We estimated a cost per DALY averted of US$ 2868 for RV5 vaccination, which corresponds to a highly cost-effective strategy from the government perspective. In the sensitivity analysis, all scenarios tested were still cost-saving or highly cost-effective from the society perspective, except in the least favorable scenario and low vaccine efficacy and disease incidence scenario. Based on the findings, introduction of rotavirus vaccine is a highly cost-effective strategy from the government perspective. Introducing the vaccine to

Long vs. short-term energy storage:sensitivity analysis.

Energy Technology Data Exchange (ETDEWEB)

Schoenung, Susan M. (Longitude 122 West, Inc., Menlo Park, CA); Hassenzahl, William V. (,Advanced Energy Analysis, Piedmont, CA)

2007-07-01

This report extends earlier work to characterize long-duration and short-duration energy storage technologies, primarily on the basis of life-cycle cost, and to investigate sensitivities to various input assumptions. Another technology--asymmetric lead-carbon capacitors--has also been added. Energy storage technologies are examined for three application categories--bulk energy storage, distributed generation, and power quality--with significant variations in discharge time and storage capacity. Sensitivity analyses include cost of electricity and natural gas, and system life, which impacts replacement costs and capital carrying charges. Results are presented in terms of annual cost, $/kW-yr. A major variable affecting system cost is hours of storage available for discharge.

A New Computationally Frugal Method For Sensitivity Analysis Of Environmental Models

Science.gov (United States)

Rakovec, O.; Hill, M. C.; Clark, M. P.; Weerts, A.; Teuling, R.; Borgonovo, E.; Uijlenhoet, R.

2013-12-01

Effective and efficient parameter sensitivity analysis methods are crucial to understand the behaviour of complex environmental models and use of models in risk assessment. This paper proposes a new computationally frugal method for analyzing parameter sensitivity: the Distributed Evaluation of Local Sensitivity Analysis (DELSA). The DELSA method can be considered a hybrid of local and global methods, and focuses explicitly on multiscale evaluation of parameter sensitivity across the parameter space. Results of the DELSA method are compared with the popular global, variance-based Sobol' method and the delta method. We assess the parameter sensitivity of both (1) a simple non-linear reservoir model with only two parameters, and (2) five different "bucket-style" hydrologic models applied to a medium-sized catchment (200 km2) in the Belgian Ardennes. Results show that in both the synthetic and real-world examples, the global Sobol' method and the DELSA method provide similar sensitivities, with the DELSA method providing more detailed insight at much lower computational cost. The ability to understand how sensitivity measures vary through parameter space with modest computational requirements provides exciting new opportunities.

Automated differentiation of computer models for sensitivity analysis

International Nuclear Information System (INIS)

Worley, B.A.

1990-01-01

Sensitivity analysis of reactor physics computer models is an established discipline after more than twenty years of active development of generalized perturbations theory based on direct and adjoint methods. Many reactor physics models have been enhanced to solve for sensitivities of model results to model data. The calculated sensitivities are usually normalized first derivatives although some codes are capable of solving for higher-order sensitivities. The purpose of this paper is to report on the development and application of the GRESS system for automating the implementation of the direct and adjoint techniques into existing FORTRAN computer codes. The GRESS system was developed at ORNL to eliminate the costly man-power intensive effort required to implement the direct and adjoint techniques into already-existing FORTRAN codes. GRESS has been successfully tested for a number of codes over a wide range of applications and presently operates on VAX machines under both VMS and UNIX operating systems

Automated differentiation of computer models for sensitivity analysis

International Nuclear Information System (INIS)

Worley, B.A.

1991-01-01

Sensitivity analysis of reactor physics computer models is an established discipline after more than twenty years of active development of generalized perturbations theory based on direct and adjoint methods. Many reactor physics models have been enhanced to solve for sensitivities of model results to model data. The calculated sensitivities are usually normalized first derivatives, although some codes are capable of solving for higher-order sensitivities. The purpose of this paper is to report on the development and application of the GRESS system for automating the implementation of the direct and adjoint techniques into existing FORTRAN computer codes. The GRESS system was developed at ORNL to eliminate the costly man-power intensive effort required to implement the direct and adjoint techniques into already-existing FORTRAN codes. GRESS has been successfully tested for a number of codes over a wide range of applications and presently operates on VAX machines under both VMS and UNIX operating systems. (author). 9 refs, 1 tab

The identification of model effective dimensions using global sensitivity analysis

International Nuclear Information System (INIS)

Kucherenko, Sergei; Feil, Balazs; Shah, Nilay; Mauntz, Wolfgang

2011-01-01

It is shown that the effective dimensions can be estimated at reasonable computational costs using variance based global sensitivity analysis. Namely, the effective dimension in the truncation sense can be found by using the Sobol' sensitivity indices for subsets of variables. The effective dimension in the superposition sense can be estimated by using the first order effects and the total Sobol' sensitivity indices. The classification of some important classes of integrable functions based on their effective dimension is proposed. It is shown that it can be used for the prediction of the QMC efficiency. Results of numerical tests verify the prediction of the developed techniques.

The identification of model effective dimensions using global sensitivity analysis

Energy Technology Data Exchange (ETDEWEB)

Kucherenko, Sergei, E-mail: s.kucherenko@ic.ac.u [CPSE, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Feil, Balazs [Department of Process Engineering, University of Pannonia, Veszprem (Hungary); Shah, Nilay [CPSE, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Mauntz, Wolfgang [Lehrstuhl fuer Anlagensteuerungstechnik, Fachbereich Chemietechnik, Universitaet Dortmund (Germany)

2011-04-15

It is shown that the effective dimensions can be estimated at reasonable computational costs using variance based global sensitivity analysis. Namely, the effective dimension in the truncation sense can be found by using the Sobol' sensitivity indices for subsets of variables. The effective dimension in the superposition sense can be estimated by using the first order effects and the total Sobol' sensitivity indices. The classification of some important classes of integrable functions based on their effective dimension is proposed. It is shown that it can be used for the prediction of the QMC efficiency. Results of numerical tests verify the prediction of the developed techniques.

Cost effectiveness analysis of immunotherapy in patients with grass pollen allergic rhinoconjunctivitis in Germany.

Science.gov (United States)

Westerhout, K Y; Verheggen, B G; Schreder, C H; Augustin, M

2012-01-01

An economic evaluation was conducted to assess the outcomes and costs as well as cost-effectiveness of the following grass-pollen immunotherapies: OA (Oralair; Stallergenes S.A., Antony, France) vs GRZ (Grazax; ALK-Abelló, Hørsholm, Denmark), and ALD (Alk Depot SQ; ALK-Abelló) (immunotherapy agents alongside symptomatic medication) and symptomatic treatment alone for grass pollen allergic rhinoconjunctivitis. The costs and outcomes of 3-year treatment were assessed for a period of 9 years using a Markov model. Treatment efficacy was estimated using an indirect comparison of available clinical trials with placebo as a common comparator. Estimates for immunotherapy discontinuation, occurrence of asthma, health state utilities, drug costs, resource use, and healthcare costs were derived from published sources. The analysis was conducted from the insurant's perspective including public and private health insurance payments and co-payments by insurants. Outcomes were reported as quality-adjusted life years (QALYs) and symptom-free days. The uncertainty around incremental model results was tested by means of extensive deterministic univariate and probabilistic multivariate sensitivity analyses. In the base case analysis the model predicted a cost-utility ratio of OA vs symptomatic treatment of €14,728 per QALY; incremental costs were €1356 (95%CI: €1230; €1484) and incremental QALYs 0.092 (95%CI: 0.052; 0.140). OA was the dominant strategy compared to GRZ and ALD, with estimated incremental costs of -€1142 (95%CI: -€1255; -€1038) and -€54 (95%CI: -€188; €85) and incremental QALYs of 0.015 (95%CI: -0.025; 0.056) and 0.027 (95%CI: -0.022; 0.075), respectively. At a willingness-to-pay threshold of €20,000, the probability of OA being the most cost-effective treatment was predicted to be 79%. Univariate sensitivity analyses show that incremental outcomes were moderately sensitive to changes in efficacy estimates. The main study limitation was the

A framework for 2-stage global sensitivity analysis of GastroPlus™ compartmental models.

Science.gov (United States)

Scherholz, Megerle L; Forder, James; Androulakis, Ioannis P

2018-04-01

Parameter sensitivity and uncertainty analysis for physiologically based pharmacokinetic (PBPK) models are becoming an important consideration for regulatory submissions, requiring further evaluation to establish the need for global sensitivity analysis. To demonstrate the benefits of an extensive analysis, global sensitivity was implemented for the GastroPlus™ model, a well-known commercially available platform, using four example drugs: acetaminophen, risperidone, atenolol, and furosemide. The capabilities of GastroPlus were expanded by developing an integrated framework to automate the GastroPlus graphical user interface with AutoIt and for execution of the sensitivity analysis in MATLAB ® . Global sensitivity analysis was performed in two stages using the Morris method to screen over 50 parameters for significant factors followed by quantitative assessment of variability using Sobol's sensitivity analysis. The 2-staged approach significantly reduced computational cost for the larger model without sacrificing interpretation of model behavior, showing that the sensitivity results were well aligned with the biopharmaceutical classification system. Both methods detected nonlinearities and parameter interactions that would have otherwise been missed by local approaches. Future work includes further exploration of how the input domain influences the calculated global sensitivity measures as well as extending the framework to consider a whole-body PBPK model.

Steady state likelihood ratio sensitivity analysis for stiff kinetic Monte Carlo simulations.

Science.gov (United States)

Núñez, M; Vlachos, D G

2015-01-28

Kinetic Monte Carlo simulation is an integral tool in the study of complex physical phenomena present in applications ranging from heterogeneous catalysis to biological systems to crystal growth and atmospheric sciences. Sensitivity analysis is useful for identifying important parameters and rate-determining steps, but the finite-difference application of sensitivity analysis is computationally demanding. Techniques based on the likelihood ratio method reduce the computational cost of sensitivity analysis by obtaining all gradient information in a single run. However, we show that disparity in time scales of microscopic events, which is ubiquitous in real systems, introduces drastic statistical noise into derivative estimates for parameters affecting the fast events. In this work, the steady-state likelihood ratio sensitivity analysis is extended to singularly perturbed systems by invoking partial equilibration for fast reactions, that is, by working on the fast and slow manifolds of the chemistry. Derivatives on each time scale are computed independently and combined to the desired sensitivity coefficients to considerably reduce the noise in derivative estimates for stiff systems. The approach is demonstrated in an analytically solvable linear system.

Cost-effectiveness analysis of implants versus autologous perforator flaps using the BREAST-Q.

Science.gov (United States)

Matros, Evan; Albornoz, Claudia R; Razdan, Shantanu N; Mehrara, Babak J; Macadam, Sheina A; Ro, Teresa; McCarthy, Colleen M; Disa, Joseph J; Cordeiro, Peter G; Pusic, Andrea L

2015-04-01

Reimbursement has been recognized as a physician barrier to autologous reconstruction. Autologous reconstructions are more expensive than prosthetic reconstructions, but provide greater health-related quality of life. The authors' hypothesis is that autologous tissue reconstructions are cost-effective compared with prosthetic techniques when considering health-related quality of life and patient satisfaction. A cost-effectiveness analysis from the payer perspective, including patient input, was performed for unilateral and bilateral reconstructions with deep inferior epigastric perforator (DIEP) flaps and implants. The effectiveness measure was derived using the BREAST-Q and interpreted as the cost for obtaining 1 year of perfect breast health-related quality-adjusted life-year. Costs were obtained from the 2010 Nationwide Inpatient Sample. The incremental cost-effectiveness ratio was generated. A sensitivity analysis for age and stage at diagnosis was performed. BREAST-Q scores from 309 patients with implants and 217 DIEP flap reconstructions were included. The additional cost for obtaining 1 year of perfect breast-related health for a unilateral DIEP flap compared with implant reconstruction was $11,941. For bilateral DIEP flaps compared with implant reconstructions, the cost for an additional breast health-related quality-adjusted life-year was $28,017. The sensitivity analysis demonstrated that the cost for an additional breast health-related quality-adjusted life-year for DIEP flaps compared with implants was less for younger patients and earlier stage breast cancer. DIEP flaps are cost-effective compared with implants, especially for unilateral reconstructions. Cost-effectiveness of autologous techniques is maximized in women with longer life expectancy. Patient-reported outcomes findings can be incorporated into cost-effectiveness analyses to demonstrate the relative value of reconstructive procedures.

Cost-Effectiveness Analysis of Preoperative Versus Postoperative Radiation Therapy in Extremity Soft Tissue Sarcoma

International Nuclear Information System (INIS)

Qu, Xuanlu M.; Louie, Alexander V.; Ashman, Jonathan; Wasif, Nabil

2017-01-01

Purpose: Surgery combined with radiation therapy (RT) is the cornerstone of multidisciplinary management of extremity soft tissue sarcoma (STS). Although RT can be given in either the preoperative or the postoperative setting with similar local recurrence and survival outcomes, the side effect profiles, costs, and long-term functional outcomes are different. The aim of this study was to use decision analysis to determine optimal sequencing of RT with surgery in patients with extremity STS. Methods and Materials: A cost-effectiveness analysis was conducted using a state transition Markov model, with quality-adjusted life years (QALYs) as the primary outcome. A time horizon of 5 years, a cycle length of 3 months, and a willingness-to-pay threshold of $50,000/QALY was used. One-way deterministic sensitivity analyses were performed to determine the thresholds at which each strategy would be preferred. The robustness of the model was assessed by probabilistic sensitivity analysis. Results: Preoperative RT is a more cost-effective strategy ($26,633/3.00 QALYs) than postoperative RT ($28,028/2.86 QALYs) in our base case scenario. Preoperative RT is the superior strategy with either 3-dimensional conformal RT or intensity-modulated RT. One-way sensitivity analyses identified the relative risk of chronic adverse events as having the greatest influence on the preferred timing of RT. The likelihood of preoperative RT being the preferred strategy was 82% on probabilistic sensitivity analysis. Conclusions: Preoperative RT is more cost effective than postoperative RT in the management of resectable extremity STS, primarily because of the higher incidence of chronic adverse events with RT in the postoperative setting.

Cost-Effectiveness Analysis of Preoperative Versus Postoperative Radiation Therapy in Extremity Soft Tissue Sarcoma

Energy Technology Data Exchange (ETDEWEB)

Qu, Xuanlu M. [Department of Oncology, Queen' s University, Kingston, Ontario (Canada); Louie, Alexander V. [Department of Radiation Oncology, London Health Sciences Center, London, Ontario (Canada); Ashman, Jonathan [Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, Arizona (United States); Wasif, Nabil, E-mail: wasif.nabil@mayo.edu [Department of General Surgery, Mayo Clinic Arizona, Phoenix, Arizona (United States)

2017-02-01

Purpose: Surgery combined with radiation therapy (RT) is the cornerstone of multidisciplinary management of extremity soft tissue sarcoma (STS). Although RT can be given in either the preoperative or the postoperative setting with similar local recurrence and survival outcomes, the side effect profiles, costs, and long-term functional outcomes are different. The aim of this study was to use decision analysis to determine optimal sequencing of RT with surgery in patients with extremity STS. Methods and Materials: A cost-effectiveness analysis was conducted using a state transition Markov model, with quality-adjusted life years (QALYs) as the primary outcome. A time horizon of 5 years, a cycle length of 3 months, and a willingness-to-pay threshold of $50,000/QALY was used. One-way deterministic sensitivity analyses were performed to determine the thresholds at which each strategy would be preferred. The robustness of the model was assessed by probabilistic sensitivity analysis. Results: Preoperative RT is a more cost-effective strategy ($26,633/3.00 QALYs) than postoperative RT ($28,028/2.86 QALYs) in our base case scenario. Preoperative RT is the superior strategy with either 3-dimensional conformal RT or intensity-modulated RT. One-way sensitivity analyses identified the relative risk of chronic adverse events as having the greatest influence on the preferred timing of RT. The likelihood of preoperative RT being the preferred strategy was 82% on probabilistic sensitivity analysis. Conclusions: Preoperative RT is more cost effective than postoperative RT in the management of resectable extremity STS, primarily because of the higher incidence of chronic adverse events with RT in the postoperative setting.

Cost analysis of Navy acquisition alternatives for the NAVSTAR Global Positioning System

Science.gov (United States)

Darcy, T. F.; Smith, G. P.

1982-12-01

This research analyzes the life cycle cost (LCC) of the Navy's current and two hypothetical procurement alternatives for NAVSTAR Global Positioning System (GPS) user equipment. Costs are derived by the ARINC Research Corporation ACBEN cost estimating system. Data presentation is in a comparative format describing individual alternative LCC and differential costs between alternatives. Sensitivity analysis explores the impact receiver-processor unit (RPU) first unit production cost has on individual alternative LCC, as well as cost differentials between each alternative. Several benefits are discussed that might provide sufficient cost savings and/or system effectiveness improvements to warrant a procurement strategy other than the existing proposal.

Timing of prophylactic surgery in prevention of diverticulitis recurrence: a cost-effectiveness analysis.

Science.gov (United States)

Richards, Robert J; Hammitt, James K

2002-09-01

Although surgery is recommended after two or more attacks of uncomplicated diverticulitis, the optimal timing for surgery in terms of cost-effectiveness is unknown. A Markov model was used to compare the costs and outcomes of performing surgery after one, two, or three uncomplicated attacks in 60-year-old hypothetical cohorts. Transition state probabilities were assigned values using published data and expert opinion. Costs were estimated from Medicare reimbursement rates. Surgery after the third attack is cost saving, yielding more years of life and quality adjusted life years at a lower cost than the other two strategies. The results were not sensitive to many of the variables tested in the model or to changes made in the discount rate (0-5%). In conclusion, performing prophylactic resection after the third attack of diverticulitis is cost saving in comparison to resection performed after the first or second attacks and remains cost-effective during sensitivity analysis.

[Operating cost analysis of anaesthesia: activity based costing (ABC analysis)].

Science.gov (United States)

Majstorović, Branislava M; Kastratović, Dragana A; Vučović, Dragan S; Milaković, Branko D; Miličić, Biljana R

2011-01-01

Cost of anaesthesiology represent defined measures to determine a precise profile of expenditure estimation of surgical treatment, which is important regarding planning of healthcare activities, prices and budget. In order to determine the actual value of anaestesiological services, we started with the analysis of activity based costing (ABC) analysis. Retrospectively, in 2005 and 2006, we estimated the direct costs of anestesiological services (salaries, drugs, supplying materials and other: analyses and equipment.) of the Institute of Anaesthesia and Resuscitation of the Clinical Centre of Serbia. The group included all anesthetized patients of both sexes and all ages. We compared direct costs with direct expenditure, "each cost object (service or unit)" of the Republican Healthcare Insurance. The Summary data of the Departments of Anaesthesia documented in the database of the Clinical Centre of Serbia. Numerical data were utilized and the numerical data were estimated and analyzed by computer programs Microsoft Office Excel 2003 and SPSS for Windows. We compared using the linear model of direct costs and unit costs of anaesthesiological services from the Costs List of the Republican Healthcare Insurance. Direct costs showed 40% of costs were spent on salaries, (32% on drugs and supplies, and 28% on other costs, such as analyses and equipment. The correlation of the direct costs of anaestesiological services showed a linear correlation with the unit costs of the Republican Healthcare Insurance. During surgery, costs of anaesthesia would increase by 10% the surgical treatment cost of patients. Regarding the actual costs of drugs and supplies, we do not see any possibility of costs reduction. Fixed elements of direct costs provide the possibility of rationalization of resources in anaesthesia.

Micosoft Excel Sensitivity Analysis for Linear and Stochastic Program Feed Formulation

Science.gov (United States)

Sensitivity analysis is a part of mathematical programming solutions and is used in making nutritional and economic decisions for a given feed formulation problem. The terms, shadow price and reduced cost, are familiar linear program (LP) terms to feed formulators. Because of the nonlinear nature of...

A cost-effect analysis of an intervention against radon in homes

Directory of Open Access Journals (Sweden)

Hein Stigum

2009-10-01

Full Text Available Background  Key words  : Radon exposure, lung cancer, cost-effect analysis, attributable risk, models-mathematical: Radon is a radioactive gas that may leak into buildings from the ground. Radon exposure is a risk factor for lung cancer. An intervention against radon exposure in homes may consist of locating homes with high radon exposure (above 200 Bq m-3 and improving these, and of protecting future houses. The purpose of this paper is to calculate the costs and the effects of this intervention. Methods: We performed a cost-effect analysis from the perspective of the society, followed by an uncertainty and sensitivity analysis. The distribution of radon levels in Norwegian homes is lognormal with mean=74.5 Bq/m3, and 7.6% above 200 Bq/m3. Results: The preventable attributable fraction of radon on lung cancer was 3.8% (95% uncertainty interval: 0.6%, 8.3%. In cumulative present values the intervention would cost $238 (145, 310 million and save 892 (133, 1981 lives, each life saved costs $0.27 (0.09, 0.9 million. The cost-effect ratio was sensitive to the radon risk, the radon exposure distribution, and the latency period of lung cancer. Together these three parameters explained 90% of the variation in the cost-effect ratio. Conclusions: Reducing the radon concentration in present and future homes to below 200 Bq/m3 will cost $0.27 (0.09, 0.9 million per life saved. The uncertainty in the estimated cost per life is large, mainly due to uncertainty in the risk of lung cancer from radon. Based on estimates from road construction, the Norwegian society has been willing to pay $1 million to save a life. We therefore conclude that the intervention against radon in homes is justifiable. The willingness to pay is also larger that the upper uncertainty limit of the cost per life. Our conclusion is therefore robust against the uncertainties in the parameters.

Comparison of global sensitivity analysis methods – Application to fuel behavior modeling

Energy Technology Data Exchange (ETDEWEB)

Ikonen, Timo, E-mail: timo.ikonen@vtt.fi

2016-02-15

Highlights: • Several global sensitivity analysis methods are compared. • The methods’ applicability to nuclear fuel performance simulations is assessed. • The implications of large input uncertainties and complex models are discussed. • Alternative strategies to perform sensitivity analyses are proposed. - Abstract: Fuel performance codes have two characteristics that make their sensitivity analysis challenging: large uncertainties in input parameters and complex, non-linear and non-additive structure of the models. The complex structure of the code leads to interactions between inputs that show as cross terms in the sensitivity analysis. Due to the large uncertainties of the inputs these interactions are significant, sometimes even dominating the sensitivity analysis. For the same reason, standard linearization techniques do not usually perform well in the analysis of fuel performance codes. More sophisticated methods are typically needed in the analysis. To this end, we compare the performance of several sensitivity analysis methods in the analysis of a steady state FRAPCON simulation. The comparison of importance rankings obtained with the various methods shows that even the simplest methods can be sufficient for the analysis of fuel maximum temperature. However, the analysis of the gap conductance requires more powerful methods that take into account the interactions of the inputs. In some cases, moment-independent methods are needed. We also investigate the computational cost of the various methods and present recommendations as to which methods to use in the analysis.

Importance measures in global sensitivity analysis of nonlinear models

International Nuclear Information System (INIS)

Homma, Toshimitsu; Saltelli, Andrea

1996-01-01

The present paper deals with a new method of global sensitivity analysis of nonlinear models. This is based on a measure of importance to calculate the fractional contribution of the input parameters to the variance of the model prediction. Measures of importance in sensitivity analysis have been suggested by several authors, whose work is reviewed in this article. More emphasis is given to the developments of sensitivity indices by the Russian mathematician I.M. Sobol'. Given that Sobol' treatment of the measure of importance is the most general, his formalism is employed throughout this paper where conceptual and computational improvements of the method are presented. The computational novelty of this study is the introduction of the 'total effect' parameter index. This index provides a measure of the total effect of a given parameter, including all the possible synergetic terms between that parameter and all the others. Rank transformation of the data is also introduced in order to increase the reproducibility of the method. These methods are tested on a few analytical and computer models. The main conclusion of this work is the identification of a sensitivity analysis methodology which is both flexible, accurate and informative, and which can be achieved at reasonable computational cost

Methodology for sensitivity analysis, approximate analysis, and design optimization in CFD for multidisciplinary applications. [computational fluid dynamics

Science.gov (United States)

Taylor, Arthur C., III; Hou, Gene W.

1992-01-01

Fundamental equations of aerodynamic sensitivity analysis and approximate analysis for the two dimensional thin layer Navier-Stokes equations are reviewed, and special boundary condition considerations necessary to apply these equations to isolated lifting airfoils on 'C' and 'O' meshes are discussed in detail. An efficient strategy which is based on the finite element method and an elastic membrane representation of the computational domain is successfully tested, which circumvents the costly 'brute force' method of obtaining grid sensitivity derivatives, and is also useful in mesh regeneration. The issue of turbulence modeling is addressed in a preliminary study. Aerodynamic shape sensitivity derivatives are efficiently calculated, and their accuracy is validated on two viscous test problems, including: (1) internal flow through a double throat nozzle, and (2) external flow over a NACA 4-digit airfoil. An automated aerodynamic design optimization strategy is outlined which includes the use of a design optimization program, an aerodynamic flow analysis code, an aerodynamic sensitivity and approximate analysis code, and a mesh regeneration and grid sensitivity analysis code. Application of the optimization methodology to the two test problems in each case resulted in a new design having a significantly improved performance in the aerodynamic response of interest.

Nonintravenous rescue medications for pediatric status epilepticus: A cost-effectiveness analysis.

Science.gov (United States)

Sánchez Fernández, Iván; Gaínza-Lein, Marina; Loddenkemper, Tobias

2017-08-01

To quantify the cost-effectiveness of rescue medications for pediatric status epilepticus: rectal diazepam, nasal midazolam, buccal midazolam, intramuscular midazolam, and nasal lorazepam. Decision analysis model populated with effectiveness data from the literature and cost data from publicly available market prices. The primary outcome was cost per seizure stopped ($/SS). One-way sensitivity analyses and second-order Monte Carlo simulations evaluated the robustness of the results across wide variations of the input parameters. The most cost-effective rescue medication was buccal midazolam (incremental cost-effectiveness ratio ([ICER]: $13.16/SS) followed by nasal midazolam (ICER: $38.19/SS). Nasal lorazepam (ICER: -$3.8/SS), intramuscular midazolam (ICER: -$64/SS), and rectal diazepam (ICER: -$2,246.21/SS) are never more cost-effective than the other options at any willingness to pay. One-way sensitivity analysis showed the following: (1) at its current effectiveness, rectal diazepam would become the most cost-effective option only if its cost was $6 or less, and (2) at its current cost, rectal diazepam would become the most cost-effective option only if effectiveness was higher than 0.89 (and only with very high willingness to pay of $2,859/SS to $31,447/SS). Second-order Monte Carlo simulations showed the following: (1) nasal midazolam and intramuscular midazolam were the more effective options; (2) the more cost-effective option was buccal midazolam for a willingness to pay from $14/SS to $41/SS and nasal midazolam for a willingness to pay above $41/SS; (3) cost-effectiveness overlapped for buccal midazolam, nasal lorazepam, intramuscular midazolam, and nasal midazolam; and (4) rectal diazepam was not cost-effective at any willingness to pay, and this conclusion remained extremely robust to wide variations of the input parameters. For pediatric status epilepticus, buccal midazolam and nasal midazolam are the most cost-effective nonintravenous rescue

Sensitivity functions for uncertainty analysis: Sensitivity and uncertainty analysis of reactor performance parameters

International Nuclear Information System (INIS)

Greenspan, E.

1982-01-01

This chapter presents the mathematical basis for sensitivity functions, discusses their physical meaning and information they contain, and clarifies a number of issues concerning their application, including the definition of group sensitivities, the selection of sensitivity functions to be included in the analysis, and limitations of sensitivity theory. Examines the theoretical foundation; criticality reset sensitivities; group sensitivities and uncertainties; selection of sensitivities included in the analysis; and other uses and limitations of sensitivity functions. Gives the theoretical formulation of sensitivity functions pertaining to ''as-built'' designs for performance parameters of the form of ratios of linear flux functionals (such as reaction-rate ratios), linear adjoint functionals, bilinear functions (such as reactivity worth ratios), and for reactor reactivity. Offers a consistent procedure for reducing energy-dependent or fine-group sensitivities and uncertainties to broad group sensitivities and uncertainties. Provides illustrations of sensitivity functions as well as references to available compilations of such functions and of total sensitivities. Indicates limitations of sensitivity theory originating from the fact that this theory is based on a first-order perturbation theory

Life cycle cost estimation and systems analysis of Waste Management Facilities

International Nuclear Information System (INIS)

Shropshire, D.; Feizollahi, F.

1995-01-01

This paper presents general conclusions from application of a system cost analysis method developed by the United States Department of Energy (DOE), Waste Management Division (WM), Waste Management Facilities Costs Information (WMFCI) program. The WMFCI method has been used to assess the DOE complex-wide management of radioactive, hazardous, and mixed wastes. The Idaho Engineering Laboratory, along with its subcontractor Morrison Knudsen Corporation, has been responsible for developing and applying the WMFCI cost analysis method. The cost analyses are based on system planning level life-cycle costs. The costs for life-cycle waste management activities estimated by WMFCI range from bench-scale testing and developmental work needed to design and construct a facility, facility permitting and startup, operation and maintenance, to the final decontamination, decommissioning, and closure of the facility. For DOE complex-wide assessments, cost estimates have been developed at the treatment, storage, and disposal module level and rolled up for each DOE installation. Discussions include conclusions reached by studies covering complex-wide consolidation of treatment, storage, and disposal facilities, system cost modeling, system costs sensitivity, system cost optimization, and the integration of WM waste with the environmental restoration and decontamination and decommissioning secondary wastes

A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus

Science.gov (United States)

Ulfsdotter, Malin

2015-01-01

Objective There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs) as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC). The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness. Methods A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data. Results The cost was €326.3 per parent, of which €53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and €272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of €47 290 per gained QALY. The sensitivity analyses resulted in ratios from €41 739 to €55 072. With the common Swedish threshold value of €55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent. Conclusion Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation. PMID:26681349

A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus.

Directory of Open Access Journals (Sweden)

Malin Ulfsdotter

Full Text Available There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC. The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness.A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data.The cost was € 326.3 per parent, of which € 53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and € 272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of € 47 290 per gained QALY. The sensitivity analyses resulted in ratios from € 41 739 to € 55 072. With the common Swedish threshold value of € 55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent.Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation.

A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus.

Science.gov (United States)

Ulfsdotter, Malin; Lindberg, Lene; Månsdotter, Anna

2015-01-01

There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs) as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC). The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness. A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data. The cost was € 326.3 per parent, of which € 53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and € 272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of € 47 290 per gained QALY. The sensitivity analyses resulted in ratios from € 41 739 to € 55 072. With the common Swedish threshold value of € 55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent. Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation.

Vasa previa screening strategies: a decision and cost-effectiveness analysis.

Science.gov (United States)

Sinkey, R G; Odibo, A O

2018-05-22

The aim of this study is to perform a decision and cost-effectiveness analysis comparing four screening strategies for the antenatal diagnosis of vasa previa among singleton pregnancies. A decision-analytic model was constructed comparing vasa previa screening strategies. Published probabilities and costs were applied to four transvaginal screening scenarios which occurred at the time of mid-trimester ultrasound: no screening, ultrasound-indicated screening, screening pregnancies conceived by in vitro fertilization (IVF), and universal screening. Ultrasound-indicated screening was defined as performing a transvaginal ultrasound at the time of routine anatomy ultrasound in response to one of the following sonographic findings associated with an increased risk of vasa previa: low-lying placenta, marginal or velamentous cord insertion, or bilobed or succenturiate lobed placenta. The primary outcome was cost per quality adjusted life years (QALY) in U.S. dollars. The analysis was from a healthcare system perspective with a willingness to pay (WTP) threshold of $100,000 per QALY selected. One-way and multivariate sensitivity analyses (Monte-Carlo simulation) were performed. This decision-analytic model demonstrated that screening pregnancies conceived by IVF was the most cost-effective strategy with an incremental cost effectiveness ratio (ICER) of $29,186.50 / QALY. Ultrasound-indicated screening was the second most cost-effective with an ICER of $56,096.77 / QALY. These data were robust to all one-way and multivariate sensitivity analyses performed. Within our baseline assumptions, transvaginal ultrasound screening for vasa previa appears to be most cost-effective when performed among IVF pregnancies. However, both IVF and ultrasound-indicated screening strategies fall within contemporary willingness-to-pay thresholds, suggesting that both strategies may be appropriate to apply in clinical practice. This article is protected by copyright. All rights reserved. This

Least Squares Shadowing Sensitivity Analysis of Chaotic Flow Around a Two-Dimensional Airfoil

Science.gov (United States)

Blonigan, Patrick J.; Wang, Qiqi; Nielsen, Eric J.; Diskin, Boris

2016-01-01

Gradient-based sensitivity analysis has proven to be an enabling technology for many applications, including design of aerospace vehicles. However, conventional sensitivity analysis methods break down when applied to long-time averages of chaotic systems. This breakdown is a serious limitation because many aerospace applications involve physical phenomena that exhibit chaotic dynamics, most notably high-resolution large-eddy and direct numerical simulations of turbulent aerodynamic flows. A recently proposed methodology, Least Squares Shadowing (LSS), avoids this breakdown and advances the state of the art in sensitivity analysis for chaotic flows. The first application of LSS to a chaotic flow simulated with a large-scale computational fluid dynamics solver is presented. The LSS sensitivity computed for this chaotic flow is verified and shown to be accurate, but the computational cost of the current LSS implementation is high.

Uranium solution mining cost estimating technique: means for rapid comparative analysis of deposits

International Nuclear Information System (INIS)

Anon.

1978-01-01

Twelve graphs provide a technique for determining relative cost ranges for uranium solution mining projects. The use of the technique can provide a consistent framework for rapid comparative analysis of various properties of mining situations. The technique is also useful to determine the sensitivities of cost figures to incremental changes in mining factors or deposit characteristics

Analysis of an inventory model for both linearly decreasing demand and holding cost

Science.gov (United States)

Malik, A. K.; Singh, Parth Raj; Tomar, Ajay; Kumar, Satish; Yadav, S. K.

2016-03-01

This study proposes the analysis of an inventory model for linearly decreasing demand and holding cost for non-instantaneous deteriorating items. The inventory model focuses on commodities having linearly decreasing demand without shortages. The holding cost doesn't remain uniform with time due to any form of variation in the time value of money. Here we consider that the holding cost decreases with respect to time. The optimal time interval for the total profit and the optimal order quantity are determined. The developed inventory model is pointed up through a numerical example. It also includes the sensitivity analysis.

The economic burden of nurse-sensitive adverse events in 22 medical-surgical units: retrospective and matching analysis.

Science.gov (United States)

Tchouaket, Eric; Dubois, Carl-Ardy; D'Amour, Danielle

2017-07-01

The aim of this study was to assess the economic burden of nurse-sensitive adverse events in 22 acute-care units in Quebec by estimating excess hospital-related costs and calculating resulting additional hospital days. Recent changes in the worldwide economic and financial contexts have made the cost of patient safety a topical issue. Yet, our knowledge about the economic burden of safety of nursing care is quite limited in Canada in general and Quebec in particular. Retrospective analysis of charts of 2699 patients hospitalized between July 2008 - August 2009 for at least 2 days of 30-day periods in 22 medical-surgical units in 11 hospitals in Quebec. Data were collected from September 2009 to August 2010. Nurse-sensitive adverse events analysed were pressure ulcers, falls, medication administration errors, pneumonia and urinary tract infections. Descriptive statistics identified numbers of cases for each nurse-sensitive adverse event. A literature analysis was used to estimate excess median hospital-related costs of treatments with these nurse-sensitive adverse events. Costs were calculated in 2014 Canadian dollars. Additional hospital days were estimated by comparing lengths of stay of patients with nurse-sensitive adverse events with those of similar patients without nurse-sensitive adverse events. This study found that five adverse events considered nurse-sensitive caused nearly 1300 additional hospital days for 166 patients and generated more than Canadian dollars 600,000 in excess treatment costs. The results present the financial consequences of the nurse-sensitive adverse events. Government should invest in prevention and in improvements to care quality and patient safety. Managers need to strengthen safety processes in their facilities and nurses should take greater precautions. © 2017 John Wiley & Sons Ltd.

Nuclear fuel cycle cost analysis using a probabilistic simulation technique

International Nuclear Information System (INIS)

Won, Il Ko; Jong, Won Choi; Chul, Hyung Kang; Jae, Sol Lee; Kun, Jai Lee

1998-01-01

A simple approach was described to incorporate the Monte Carlo simulation technique into a fuel cycle cost estimate. As a case study, the once-through and recycle fuel cycle options were tested with some alternatives (ie. the change of distribution type for input parameters), and the simulation results were compared with the values calculated by a deterministic method. A three-estimate approach was used for converting cost inputs into the statistical parameters of assumed probabilistic distributions. It was indicated that the Monte Carlo simulation by a Latin Hypercube Sampling technique and subsequent sensitivity analyses were useful for examining uncertainty propagation of fuel cycle costs, and could more efficiently provide information to decisions makers than a deterministic method. It was shown from the change of distribution types of input parameters that the values calculated by the deterministic method were set around a 40 th ∼ 50 th percentile of the output distribution function calculated by probabilistic simulation. Assuming lognormal distribution of inputs, however, the values calculated by the deterministic method were set around an 85 th percentile of the output distribution function calculated by probabilistic simulation. It was also indicated from the results of the sensitivity analysis that the front-end components were generally more sensitive than the back-end components, of which the uranium purchase cost was the most important factor of all. It showed, also, that the discount rate made many contributions to the fuel cycle cost, showing the rank of third or fifth of all components. The results of this study could be useful in applications to another options, such as the Dcp (Direct Use of PWR spent fuel In Candu reactors) cycle with high cost uncertainty

Challenges from variation across regions in cost effectiveness analysis in multi-regional clinical trials

Directory of Open Access Journals (Sweden)

Yunbo Chu

2016-10-01

Full Text Available Economic evaluation in the form of cost-effectiveness analysis has become a popular means to inform decisions in healthcare. With multi-regional clinical trials in a global development program becoming a new venue for drug efficacy testing in recent decades, questions in methods for cost-effectiveness analysis in the multi-regional clinical trials setting also emerge. This paper addresses some challenges from variation across regions in cost effectiveness analysis in multi-regional clinical trials. Several discussion points are raised for further attention and a multi-regional clinical trial example is presented to illustrate the implications in industrial application. A general message is delivered to call for a depth discussion by all stakeholders to reach an agreement on a good practice in cost-effectiveness analysis in the multi-regional clinical trials. Meanwhile, we recommend an additional consideration of cost-effectiveness analysis results based on the clinical evidence from a certain homogeneous population as sensitivity or scenario analysis upon data availability.

Cost-Effectiveness/Cost-Benefit Analysis of Newborn Screening for Severe Combined Immune Deficiency in Washington State.

Science.gov (United States)

Ding, Yao; Thompson, John D; Kobrynski, Lisa; Ojodu, Jelili; Zarbalian, Guisou; Grosse, Scott D

2016-05-01

To evaluate the expected cost-effectiveness and net benefit of the recent implementation of newborn screening (NBS) for severe combined immunodeficiency (SCID) in Washington State. We constructed a decision analysis model to estimate the costs and benefits of NBS in an annual birth cohort of 86 600 infants based on projections of avoided infant deaths. Point estimates and ranges for input variables, including the birth prevalence of SCID, proportion detected asymptomatically without screening through family history, screening test characteristics, survival rates, and costs of screening, diagnosis, and treatment were derived from published estimates, expert opinion, and the Washington NBS program. We estimated treatment costs stratified by age of identification and SCID type (with or without adenosine deaminase deficiency). Economic benefit was estimated using values of $4.2 and $9.0 million per death averted. We performed sensitivity analyses to evaluate the influence of key variables on the incremental cost-effectiveness ratio (ICER) of net direct cost per life-year saved. Our model predicts an additional 1.19 newborn infants with SCID detected preclinically through screening, in addition to those who would have been detected early through family history, and 0.40 deaths averted annually. Our base-case model suggests an ICER of $35 311 per life-year saved, and a benefit-cost ratio of either 5.31 or 2.71. Sensitivity analyses found ICER values <$100 000 and positive net benefit for plausible assumptions on all variables. Our model suggests that NBS for SCID in Washington is likely to be cost-effective and to show positive net economic benefit. Published by Elsevier Inc.

Cost-utility analysis of the National truth campaign to prevent youth smoking.

Science.gov (United States)

Holtgrave, David R; Wunderink, Katherine A; Vallone, Donna M; Healton, Cheryl G

2009-05-01

In 2005, the American Journal of Public Health published an article that indicated that 22% of the overall decline in youth smoking that occurred between 1999 and 2002 was directly attributable to the truth social marketing campaign launched in 2000. A remaining key question about the truth campaign is whether the economic investment in the program can be justified by the public health outcomes; that question is examined here. Standard methods of cost and cost-utility analysis were employed in accordance with the U.S. Panel on Cost-Effectiveness in Health and Medicine; a societal perspective was employed. During 2000-2002, expenditures totaled just over $324 million to develop, deliver, evaluate, and litigate the truth campaign. The base-case cost-utility analysis result indicates that the campaign was cost saving; it is estimated that the campaign recouped its costs and that just under $1.9 billion in medical costs was averted for society. Sensitivity analysis indicated that the basic determination of cost effectiveness for this campaign is robust to substantial variation in input parameters. This study suggests that the truth campaign not only markedly improved the public's health but did so in an economically efficient manner.

[Cost-benefit analysis of the active screening of pulmonary tuberculosis in a recluse population entering prison].

Science.gov (United States)

Martín, V; Domínguez, A; Alcaide, J

1997-01-01

In spanish prisons, tuberculosis is a serious problem of public health and health authorities don't take it seriously. To prove the efficiency of pulmonary tuberculosis case-finding on arrival at prison in order to get location resources in this activity. Cost-benefit analysis of a case-finding program compared with to wait for diagnostic to illness. The sensitivity of test was fixed in 80% and the specificity in 99.99%. The cost was based on market prices. Sensitivity analysis was done in every variables as well as tridimensional analysis in those one of more influence. The case-finding was efficient on prevalences of tuberculosis over 5 per mil. Its efficiency was hardly affected by discount social rates or the sensitivity of diagnostic tests. The prevalence of illness, the cost of diagnostic activities as well as the success of treatment and the specificity of diagnostic tests used had as influence on the efficiency model. The tridimensional analysis proved that the case-finding of pulmonary tuberculosis has efficiency on low prevalences (1 per thousand), provided the number of people cured is a 5% higher than the alternative one and the costs of case-finding less than 1,000 pesetas per subject. The case-finding pulmonary tuberculosis on arrival at prisons is of high efficiency. In a cost-opportunity situation (location of available resources, penitentiary and extrapenitentiary) the program is very efficacious taking into account the fact of higher prevalence of pulmonary tuberculosis in this people.

Global sensitivity analysis using a Gaussian Radial Basis Function metamodel

International Nuclear Information System (INIS)

Wu, Zeping; Wang, Donghui; Okolo N, Patrick; Hu, Fan; Zhang, Weihua

2016-01-01

Sensitivity analysis plays an important role in exploring the actual impact of adjustable parameters on response variables. Amongst the wide range of documented studies on sensitivity measures and analysis, Sobol' indices have received greater portion of attention due to the fact that they can provide accurate information for most models. In this paper, a novel analytical expression to compute the Sobol' indices is derived by introducing a method which uses the Gaussian Radial Basis Function to build metamodels of computationally expensive computer codes. Performance of the proposed method is validated against various analytical functions and also a structural simulation scenario. Results demonstrate that the proposed method is an efficient approach, requiring a computational cost of one to two orders of magnitude less when compared to the traditional Quasi Monte Carlo-based evaluation of Sobol' indices. - Highlights: • RBF based sensitivity analysis method is proposed. • Sobol' decomposition of Gaussian RBF metamodel is obtained. • Sobol' indices of Gaussian RBF metamodel are derived based on the decomposition. • The efficiency of proposed method is validated by some numerical examples.

Cost-effectiveness analysis of treatment alternatives for beef bulls with preputial prolapse.

Science.gov (United States)

Kasari, T R; McGrann, J M; Hooper, R N

1997-10-01

To develop an economic model for comparing cost-effectiveness of medical and surgical treatment versus replacement of beef bulls with preputial prolapse. Economic analysis. Estimates determined from medical records of bulls treated for preputial prolapse at our hospital and from information about treatment of bulls published elsewhere. Annual depreciation cost for treatment (ADC(T)) and replacement (ADC(R)) were calculated. Total investment for an injured bull equaled the sum of salvage value, maintenance cost, and expected cost of the treatment option under consideration. Total investment for a replacement bull was purchase price. Net present value of cost was calculated for each year of bull use. Sensitivity analyses were constructed to determine the value that would warrant treatment of an injured bull. The decision to treat was indicated when ADC(T) was less than ADC(R). In our example, it was more cost-effective for owners to cull an injured bull. The ADC(R) was $97 less than ADC(T) for medical treatment ($365 vs $462) and $280 less than ADC(T) for surgical treatment ($365 vs $645). Likewise, net present value of cost values indicated that it was more cost-effective for owners to cull an injured bull. Sensitivity analysis indicated treatment decisions were justified on the basis of replacement value or planned number of breeding seasons remaining for the bull. The model described here can be used by practitioners to provide an objective basis to guide decision making of owners who seek advice on whether to treat or replace bulls with preputial prolapse.

A cost-benefit/cost-effectiveness analysis of proposed supervised injection facilities in Ottawa, Canada.

Science.gov (United States)

Jozaghi, Ehsan; Reid, Andrew A; Andresen, Martin A; Juneau, Alexandre

2014-08-04

Supervised injection facilities (SIFs) are venues where people who inject drugs (PWID) have access to a clean and medically supervised environment in which they can safely inject their own illicit drugs. There is currently only one legal SIF in North America: Insite in Vancouver, British Columbia, Canada. The responses and feedback generated by the evaluations of Insite in Vancouver have been overwhelmingly positive. This study assesses whether the above mentioned facility in the Downtown Eastside of Vancouver needs to be expanded to other locations, more specifically that of Canada's capital city, Ottawa. The current study is aimed at contributing to the existing literature on health policy by conducting cost-benefit and cost-effective analyses for the opening of SIFs in Ottawa, Ontario. In particular, the costs of operating numerous SIFs in Ottawa was compared to the savings incurred; this was done after accounting for the prevention of new HIV and Hepatitis C (HCV) infections. To ensure accuracy, two distinct mathematical models and a sensitivity analysis were employed. The sensitivity analyses conducted with the models reveals the potential for SIFs in Ottawa to be a fiscally responsible harm reduction strategy for the prevention of HCV cases--when considered independently. With a baseline sharing rate of 19%, the cumulative annual cost model supported the establishment of two SIFs and the marginal annual cost model supported the establishment of a single SIF. More often, the prevention of HIV or HCV alone were not sufficient to justify the establishment cost-effectiveness; rather, only when both HIV and HCV are considered does sufficient economic support became apparent. Funded supervised injection facilities in Ottawa appear to be an efficient and effective use of financial resources in the public health domain.

Drilling cost analysis

International Nuclear Information System (INIS)

Anand, A.B.

1992-01-01

Drilling assumes greater importance in present day uranium exploration which emphasizes to explore more areas on the basis of conceptual model than merely on surface anomalies. But drilling is as costly as it is important and consumes a major share (50% to 60%) of the exploration budget. As such the cost of drilling has great bearing on the exploration strategy as well as on the overall cost of the project. Therefore, understanding the cost analysis is very much important when planning or intensifying an exploration programme. This not only helps in controlling the current operations but also in planning the budgetary provisions for future operations. Also, if the work is entrusted to a private party, knowledge of in-house cost analysis helps in fixing the rates of drilling in different formations and areas to be drilled. Under this topic, various factors that contribute to the cost of drilling per meter as well as ways to minimize the drilling cost for better economic evaluation of mineral deposits are discussed. (author)

Cost-consequence analysis of different active flowable hemostatic matrices in cardiac surgical procedures.

Science.gov (United States)

Makhija, D; Rock, M; Xiong, Y; Epstein, J D; Arnold, M R; Lattouf, O M; Calcaterra, D

2017-06-01

A recent retrospective comparative effectiveness study found that use of the FLOSEAL Hemostatic Matrix in cardiac surgery was associated with significantly lower risks of complications, blood transfusions, surgical revisions, and shorter length of surgery than use of SURGIFLO Hemostatic Matrix. These outcome improvements in cardiac surgery procedures may translate to economic savings for hospitals and payers. The objective of this study was to estimate the cost-consequence of two flowable hemostatic matrices (FLOSEAL or SURGIFLO) in cardiac surgeries for US hospitals. A cost-consequence model was constructed using clinical outcomes from a previously published retrospective comparative effectiveness study of FLOSEAL vs SURGIFLO in adult cardiac surgeries. The model accounted for the reported differences between these products in length of surgery, rates of major and minor complications, surgical revisions, and blood product transfusions. Costs were derived from Healthcare Cost and Utilization Project's National Inpatient Sample (NIS) 2012 database and converted to 2015 US dollars. Savings were modeled for a hospital performing 245 cardiac surgeries annually, as identified as the average for hospitals in the NIS dataset. One-way sensitivity analysis and probabilistic sensitivity analysis were performed to test model robustness. The results suggest that if FLOSEAL is utilized in a hospital that performs 245 mixed cardiac surgery procedures annually, 11 major complications, 31 minor complications, nine surgical revisions, 79 blood product transfusions, and 260.3 h of cumulative operating time could be avoided. These improved outcomes correspond to a net annualized saving of $1,532,896. Cost savings remained consistent between $1.3m and $1.8m and between $911k and $2.4m, even after accounting for the uncertainty around clinical and cost inputs, in a one-way and probabilistic sensitivity analysis, respectively. Outcome differences associated with FLOSEAL vs SURGIFLO

Sensitivity Analysis of Multidisciplinary Rotorcraft Simulations

Science.gov (United States)

Wang, Li; Diskin, Boris; Biedron, Robert T.; Nielsen, Eric J.; Bauchau, Olivier A.

2017-01-01

A multidisciplinary sensitivity analysis of rotorcraft simulations involving tightly coupled high-fidelity computational fluid dynamics and comprehensive analysis solvers is presented and evaluated. An unstructured sensitivity-enabled Navier-Stokes solver, FUN3D, and a nonlinear flexible multibody dynamics solver, DYMORE, are coupled to predict the aerodynamic loads and structural responses of helicopter rotor blades. A discretely-consistent adjoint-based sensitivity analysis available in FUN3D provides sensitivities arising from unsteady turbulent flows and unstructured dynamic overset meshes, while a complex-variable approach is used to compute DYMORE structural sensitivities with respect to aerodynamic loads. The multidisciplinary sensitivity analysis is conducted through integrating the sensitivity components from each discipline of the coupled system. Numerical results verify accuracy of the FUN3D/DYMORE system by conducting simulations for a benchmark rotorcraft test model and comparing solutions with established analyses and experimental data. Complex-variable implementation of sensitivity analysis of DYMORE and the coupled FUN3D/DYMORE system is verified by comparing with real-valued analysis and sensitivities. Correctness of adjoint formulations for FUN3D/DYMORE interfaces is verified by comparing adjoint-based and complex-variable sensitivities. Finally, sensitivities of the lift and drag functions obtained by complex-variable FUN3D/DYMORE simulations are compared with sensitivities computed by the multidisciplinary sensitivity analysis, which couples adjoint-based flow and grid sensitivities of FUN3D and FUN3D/DYMORE interfaces with complex-variable sensitivities of DYMORE structural responses.

Serological testing versus other strategies for diagnosis of active tuberculosis in India: a cost-effectiveness analysis.

Directory of Open Access Journals (Sweden)

David W Dowdy

2011-08-01

Full Text Available Undiagnosed and misdiagnosed tuberculosis (TB drives the epidemic in India. Serological (antibody detection TB tests are not recommended by any agency, but widely used in many countries, including the Indian private sector. The cost and impact of using serology compared with other diagnostic techniques is unknown.Taking a patient cohort conservatively equal to the annual number of serological tests done in India (1.5 million adults suspected of having active TB, we used decision analysis to estimate costs and effectiveness of sputum smear microscopy (US$3.62 for two smears, microscopy plus automated liquid culture (mycobacterium growth indicator tube [MGIT], US$20/test, and serological testing (anda-tb ELISA, US$20/test. Data on test accuracy and costs were obtained from published literature. We adopted the perspective of the Indian TB control sector and an analysis frame of 1 year. Our primary outcome was the incremental cost per disability-adjusted life year (DALY averted. We performed one-way sensitivity analysis on all model parameters, with multiway sensitivity analysis on variables to which the model was most sensitive. If used instead of sputum microscopy, serology generated an estimated 14,000 more TB diagnoses, but also 121,000 more false-positive diagnoses, 102,000 fewer DALYs averted, and 32,000 more secondary TB cases than microscopy, at approximately four times the incremental cost (US$47.5 million versus US$11.9 million. When added to high-quality sputum smears, MGIT culture was estimated to avert 130,000 incremental DALYs at an incremental cost of US$213 per DALY averted. Serology was dominated by (i.e., more costly and less effective than MGIT culture and remained less economically favorable than sputum smear or TB culture in one-way and multiway sensitivity analyses.In India, sputum smear microscopy remains the most cost-effective diagnostic test available for active TB; efforts to increase access to quality-assured microscopy

A cost-effectiveness analysis of typhoid fever vaccines in US military personnel.

Science.gov (United States)

Warren, T A; Finder, S F; Brier, K L; Ries, A J; Weber, M P; Miller, M R; Potyk, R P; Reeves, C S; Moran, E L; Tornow, J J

1996-11-01

Typhoid fever has been a problem for military personnel throughout history. A cost-effectiveness analysis of typhoid fever vaccines from the perspective of the US military was performed. Currently 3 vaccine preparations are available in the US: an oral live Type 21A whole cell vaccine; a single-dose parenteral, cell subunit vaccine; and a 2-dose parenteral heat-phenol killed, whole cell vaccine. This analysis assumed all vaccinees were US military personnel. Two pharmacoeconomic models were developed, one for personnel who have not yet been deployed, and the other for personnel who are deployed to an area endemic for typhoid fever. Drug acquisition, administration, adverse effect and lost work costs, as well as the costs associated with typhoid fever, were included in this analysis. Unique military issues, typhoid fever attack rates, vaccine efficacy, and compliance with each vaccine's dosage regimen were included in this analysis. A sensitivity analysis was performed to test the robustness of the models. Typhoid fever immunisation is not cost-effective for US military personnel unless they are considered imminently deployable or are deployed. The most cost-effective vaccine for US military personnel is the single-dose, cell subunit parenteral vaccine.

Life-Cycle Cost-Benefit Analysis

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

2010-01-01

The future use of Life-Cycle Cost-Benefit (LCCB) analysis is discussed in this paper. A more complete analysis including not only the traditional factors and user costs, but also factors which are difficult to include in the analysis is needed in the future.......The future use of Life-Cycle Cost-Benefit (LCCB) analysis is discussed in this paper. A more complete analysis including not only the traditional factors and user costs, but also factors which are difficult to include in the analysis is needed in the future....

Cost-effectiveness analysis of antithyroid drug therapy, 131I therapy and subtotal thyroidectomy for Graves' disease

International Nuclear Information System (INIS)

Yano, Fuzuki; Watanabe, Sadahiro; Hayashi, Katsumi; Kita, Tamotsu; Yamamoto, Masayoshi; Kosuda, Shigeru; Tanaka, Yuji

2007-01-01

The objective of this study was to assess the cost-effectiveness of antithyroid drug (ATD) therapy vs. radioiodine therapy (RIT) vs. subtotal thyroidectomy (STT) by calculating expected lifelong cost and utility based on Graves' disease patients' responses to questionnaires using a decision-tree sensitivity analysis and relevant variables. The decision-tree sensitivity analysis to determine expected lifelong cost and utility in Graves' disease patients was designed on the basis of the 4 competing strategies consisting of: (1) ATD therapy plus RIT strategy, (2) ATD therapy plus STT strategy, (3) low-fixed-dose (185 MBq) RIT alone strategy, and (4) high-fixed-dose (370 MBq) RIT alone strategy. One-way sensitivity analysis was designed in the ATD therapy plus RIT strategy, for replacement with RIT in place of ATD, ranging from a 1% incidence of ATD side effects to 30%. The low-fixed-dose RIT alone strategy was least costly, and the high-fixed-dose RIT alone strategy most costly. The lifelong utility of high-fixed-dose RIT alone strategy with a 5% rate of discounting was highest (lifelong utility for 30 years: 15.2/patient), and the utility of the ATD plus RIT strategy with 1% side effects of the ATD was lowest (14.1/patient). The cost-effectiveness ratio was lowest (yen 5 008/utility) in a low-fixed-dose RIT alone strategy. In conclusion, a low-fixed-dose RIT alone strategy is preferred treatments in view of cost-effectiveness ratio, and RIT should be used more widely in Japan. (author)

Cost-effectiveness in the management of Dupuytren's contracture. A Canadian cost-utility analysis of current and future management strategies.

Science.gov (United States)

Baltzer, H; Binhammer, P A

2013-08-01

In Canada, Dupuytren's contracture is managed with partial fasciectomy or percutaneous needle aponeurotomy (PNA). Injectable collagenase will soon be available. The optimal management of Dupuytren's contracture is controversial and trade-offs exist between the different methods. Using a cost-utility analysis approach, our aim was to identify the most cost-effective form of treatment for managing Dupuytren's contracture it and the threshold at which collagenase is cost-effective. We developed an expected-value decision analysis model for Dupuytren's contracture affecting a single finger, comparing the cost-effectiveness of fasciectomy, aponeurotomy and collagenase from a societal perspective. Cost-effectiveness, one-way sensitivity and variability analyses were performed using standard thresholds for cost effective treatment ($50 000 to $100 000/QALY gained). Percutaneous needle aponeurotomy was the preferred strategy for managing contractures affecting a single finger. The cost-effectiveness of primary aponeurotomy improved when repeated to treat recurrence. Fasciectomy was not cost-effective. Collagenase was cost-effective relative to and preferred over aponeurotomy at $875 and $470 per course of treatment, respectively. In summary, our model supports the trend towards non-surgical interventions for managing Dupuytren's contracture affecting a single finger. Injectable collagenase will only be feasible in our publicly funded healthcare system if it costs significantly less than current United States pricing.

A Cost-Effectiveness Analysis of Clopidogrel for Patients with Non-ST-Segment Elevation Acute Coronary Syndrome in China.

Science.gov (United States)

Cui, Ming; Tu, Chen Chen; Chen, Er Zhen; Wang, Xiao Li; Tan, Seng Chuen; Chen, Can

2016-09-01

There are a number of economic evaluation studies of clopidogrel for patients with non-ST-segment elevation acute coronary syndrome (NSTEACS) published from the perspective of multiple countries in recent years. However, relevant research is quite limited in China. We aimed to estimate the long-term cost effectiveness for up to 1-year treatment with clopidogrel plus acetylsalicylic acid (ASA) versus ASA alone for NSTEACS from the public payer perspective in China. This analysis used a Markov model to simulate a cohort of patients for quality-adjusted life years (QALYs) gained and incremental cost for lifetime horizon. Based on the primary event rates, adherence rate, and mortality derived from the CURE trial, hazard functions obtained from published literature were used to extrapolate the overall survival to lifetime horizon. Resource utilization, hospitalization, medication costs, and utility values were estimated from official reports, published literature, and analysis of the patient-level insurance data in China. To assess the impact of parameters' uncertainty on cost-effectiveness results, one-way sensitivity analyses were undertaken for key parameters, and probabilistic sensitivity analysis (PSA) was conducted using the Monte Carlo simulation. The therapy of clopidogrel plus ASA is a cost-effective option in comparison with ASA alone for the treatment of NSTEACS in China, leading to 0.0548 life years (LYs) and 0.0518 QALYs gained per patient. From the public payer perspective in China, clopidogrel plus ASA is associated with an incremental cost of 43,340 China Yuan (CNY) per QALY gained and 41,030 CNY per LY gained (discounting at 3.5% per year). PSA results demonstrated that 88% of simulations were lower than the cost-effectiveness threshold of 150,721 CYN per QALY gained. Based on the one-way sensitivity analysis, results are most sensitive to price of clopidogrel, but remain well below this threshold. This analysis suggests that treatment with

Missing data in trial-based cost-effectiveness analysis: An incomplete journey.

Science.gov (United States)

Leurent, Baptiste; Gomes, Manuel; Carpenter, James R

2018-06-01

Cost-effectiveness analyses (CEA) conducted alongside randomised trials provide key evidence for informing healthcare decision making, but missing data pose substantive challenges. Recently, there have been a number of developments in methods and guidelines addressing missing data in trials. However, it is unclear whether these developments have permeated CEA practice. This paper critically reviews the extent of and methods used to address missing data in recently published trial-based CEA. Issues of the Health Technology Assessment journal from 2013 to 2015 were searched. Fifty-two eligible studies were identified. Missing data were very common; the median proportion of trial participants with complete cost-effectiveness data was 63% (interquartile range: 47%-81%). The most common approach for the primary analysis was to restrict analysis to those with complete data (43%), followed by multiple imputation (30%). Half of the studies conducted some sort of sensitivity analyses, but only 2 (4%) considered possible departures from the missing-at-random assumption. Further improvements are needed to address missing data in cost-effectiveness analyses conducted alongside randomised trials. These should focus on limiting the extent of missing data, choosing an appropriate method for the primary analysis that is valid under contextually plausible assumptions, and conducting sensitivity analyses to departures from the missing-at-random assumption. © 2018 The Authors Health Economics published by John Wiley & Sons Ltd.

Cost-Effectiveness Analysis of Isavuconazole vs. Voriconazole as First-Line Treatment for Invasive Aspergillosis.

Science.gov (United States)

Harrington, Rachel; Lee, Edward; Yang, Hongbo; Wei, Jin; Messali, Andrew; Azie, Nkechi; Wu, Eric Q; Spalding, James

2017-01-01

Invasive aspergillosis (IA) is associated with a significant clinical and economic burden. The phase III SECURE trial demonstrated non-inferiority in clinical efficacy between isavuconazole and voriconazole. No studies have evaluated the cost-effectiveness of isavuconazole compared to voriconazole. The objective of this study was to evaluate the costs and cost-effectiveness of isavuconazole vs. voriconazole for the first-line treatment of IA from the US hospital perspective. An economic model was developed to assess the costs and cost-effectiveness of isavuconazole vs. voriconazole in hospitalized patients with IA. The time horizon was the duration of hospitalization. Length of stay for the initial admission, incidence of readmission, clinical response, overall survival rates, and experience of adverse events (AEs) came from the SECURE trial. Unit costs were from the literature. Total costs per patient were estimated, composed of drug costs, costs of AEs, and costs of hospitalizations. Incremental costs per death avoided and per additional clinical responders were reported. Deterministic and probabilistic sensitivity analyses (DSA and PSA) were conducted. Base case analysis showed that isavuconazole was associated with a $7418 lower total cost per patient than voriconazole. In both incremental costs per death avoided and incremental costs per additional clinical responder, isavuconazole dominated voriconazole. Results were robust in sensitivity analysis. Isavuconazole was cost saving and dominant vs. voriconazole in most DSA. In PSA, isavuconazole was cost saving in 80.2% of the simulations and cost-effective in 82.0% of the simulations at the $50,000 willingness to pay threshold per additional outcome. Isavuconazole is a cost-effective option for the treatment of IA among hospitalized patients. Astellas Pharma Global Development, Inc.

Cost Analysis of a High Support Housing Initiative for Persons with Severe Mental Illness and Long-Term Psychiatric Hospitalization.

Science.gov (United States)

Rudoler, David; de Oliveira, Claire; Jacob, Binu; Hopkins, Melonie; Kurdyak, Paul

2018-01-01

The objective of this article was to conduct a cost analysis comparing the costs of a supportive housing intervention to inpatient care for clients with severe mental illness who were designated alternative-level care while inpatient at the Centre for Addiction and Mental Health in Toronto. The intervention, called the High Support Housing Initiative, was implemented in 2013 through a collaboration between 15 agencies in the Toronto area. The perspective of this cost analysis was that of the Ontario Ministry of Health and Long-Term Care. We compared the cost of inpatient mental health care to high-support housing. Cost data were derived from a variety of sources, including health administrative data, expenditures reported by housing providers, and document analysis. The High Support Housing Initiative was cost saving relative to inpatient care. The average cost savings per diem were between $140 and $160. This amounts to an annual cost savings of approximately $51,000 to $58,000. When tested through sensitivity analysis, the intervention remained cost saving in most scenarios; however, the result was highly sensitive to health system costs for clients of the High Support Housing Initiative program. This study suggests the High Support Housing Initiative is potentially cost saving relative to inpatient hospitalization at the Centre for Addiction and Mental Health.

Cost-effectiveness analysis of two treatment strategies for chronic hepatitis C before and after access to direct-acting antivirals in Spain.

Science.gov (United States)

Turnes, Juan; Domínguez-Hernández, Raquel; Casado, Miguel Ángel

To evaluate the cost-effectiveness of a strategy based on direct-acting antivirals (DAAs) following the marketing of simeprevir and sofosbuvir (post-DAA) versus a pre-direct-acting antiviral strategy (pre-DAA) in patients with chronic hepatitis C, from the perspective of the Spanish National Health System. A decision tree combined with a Markov model was used to estimate the direct health costs (€, 2016) and health outcomes (quality-adjusted life years, QALYs) throughout the patient's life, with an annual discount rate of 3%. The sustained virological response, percentage of patients treated or not treated in each strategy, clinical characteristics of the patients, annual likelihood of transition, costs of treating and managing the disease, and utilities were obtained from the literature. The cost-effectiveness analysis was expressed as an incremental cost-effectiveness ratio (incremental cost per QALY gained). A deterministic sensitivity analysis and a probabilistic sensitivity analysis were performed. The post-DAA strategy showed higher health costs per patient (€30,944 vs. €23,707) than the pre-DAA strategy. However, it was associated with an increase of QALYs gained (15.79 vs. 12.83), showing an incremental cost-effectiveness ratio of €2,439 per QALY. The deterministic sensitivity analysis and the probabilistic sensitivity analysis showed the robustness of the results, with the post-DAA strategy being cost-effective in 99% of cases compared to the pre-DAA strategy. Compared to the pre-DAA strategy, the post-DAA strategy is efficient for the treatment of chronic hepatitis C in Spain, resulting in a much lower cost per QALY than the efficiency threshold used in Spain (€30,000 per QALY). Copyright © 2017 Elsevier España, S.L.U., AEEH y AEG. All rights reserved.

Cost-effectiveness analysis of pneumococcal vaccination for infants in China.

Science.gov (United States)

Maurer, Kristin A; Chen, Huey-Fen; Wagner, Abram L; Hegde, Sonia T; Patel, Tejasi; Boulton, Matthew L; Hutton, David W

2016-12-07

Although China has a high burden of pneumococcal disease among young children, the government does not administer publicly-funded pneumococcal conjugate vaccines (PCV) through its Expanded Program on Immunization (EPI). We evaluated the cost-effectiveness of publicly-funded PCV-7, PCV-10, and PCV-13 vaccination programs for infants in China. Using a Markov model, we simulated a cohort of 16 million Chinese infants to estimate the impact of PCV-7, PCV-10, and PCV-13 vaccination programs from a societal perspective. We extrapolated health states to estimate the effects of the programs over the course of a lifetime of 75years. Parameters in the model were derived from a review of the literature. We found that PCV-7, PCV-10, and PCV-13 vaccination programs would be cost-effective compared to no vaccination. However, PCV-13 had the lowest incremental cost-effectiveness ratio ($11,464/QALY vs $16,664/QALY for PCV-10 and $18,224/QALY for PCV-7) due to a reduction in overall costs. Our sensitivity analysis revealed that the incremental cost-effectiveness ratios were most sensitive to the utility of acute otitis media, the cost of PCV-13, and the incidence of pneumonia and acute otitis media. The Chinese government should take steps to reduce the burden of pneumococcal diseases among young children through the inclusion of a pneumococcal conjugate vaccine in its EPI. Although all vaccinations would be cost-effective, PCV-13 would save more costs to the healthcare system and would be the preferred strategy. Copyright © 2016 Elsevier Ltd. All rights reserved.

A cost-effectiveness and cost-utility analysis of radiosurgery vs. resection for single-brain metastases

International Nuclear Information System (INIS)

Mehta, Minesh; Noyes, William; Craig, Bruce; Lamond, John; Auchter, Richard; French, Molly; Johnson, Mark; Levin, Allan; Badie, Behnam; Robbins, Ian; Kinsella, Timothy

1997-01-01

determined. To calculate the societal or national impact of these practices, the proportion of patients potentially eligible for aggressive management was estimated and the financial impact was determined using various utilization ratios for radiosurgery and surgery. Results: Both resection and radiosurgery yielded superior survival and functional independence, compared to whole brain radiotherapy alone, with minor differences in outcome between the two modalities; resection resulted in a 1.8-fold increase in cost, compared to radiosurgery. The latter modality yielded superior cost outcomes on all measures, even when a sensitivity analysis of up to 50% was performed. A reversal estimate indicated that in order for surgery to yield equal cost effectiveness, its cost would have to decrease by 48% or median survival would have to improve by 108%. The average cost per week of survival was $310 for radiotherapy, $524 for resection plus radiation, and $270 for radiosurgery plus radiation. Conclusions: For selected patients, aggressive strategies such as resection or radiosurgery are warranted, as they result in improved median survival and functional independence. Radiosurgery appears to be the more cost-effective procedure

Cost utility analysis of endoscopic biliary stent in unresectable hilar cholangiocarcinoma: decision analytic modeling approach.

Science.gov (United States)

Sangchan, Apichat; Chaiyakunapruk, Nathorn; Supakankunti, Siripen; Pugkhem, Ake; Mairiang, Pisaln

2014-01-01

Endoscopic biliary drainage using metal and plastic stent in unresectable hilar cholangiocarcinoma (HCA) is widely used but little is known about their cost-effectiveness. This study evaluated the cost-utility of endoscopic metal and plastic stent drainage in unresectable complex, Bismuth type II-IV, HCA patients. Decision analytic model, Markov model, was used to evaluate cost and quality-adjusted life year (QALY) of endoscopic biliary drainage in unresectable HCA. Costs of treatment and utilities of each Markov state were retrieved from hospital charges and unresectable HCA patients from tertiary care hospital in Thailand, respectively. Transition probabilities were derived from international literature. Base case analyses and sensitivity analyses were performed. Under the base-case analysis, metal stent is more effective but more expensive than plastic stent. An incremental cost per additional QALY gained is 192,650 baht (US$ 6,318). From probabilistic sensitivity analysis, at the willingness to pay threshold of one and three times GDP per capita or 158,000 baht (US$ 5,182) and 474,000 baht (US$ 15,546), the probability of metal stent being cost-effective is 26.4% and 99.8%, respectively. Based on the WHO recommendation regarding the cost-effectiveness threshold criteria, endoscopic metal stent drainage is cost-effective compared to plastic stent in unresectable complex HCA.

Cost analysis and provider satisfaction with pediatrician in triage.

Science.gov (United States)

Kezirian, Janice; Muhammad, Warees T; Wan, Jim Y; Godambe, Sandip A; Pershad, Jay

2012-10-01

The goals of this study were to (1) conduct a cost-benefit analysis, from a hospital's perspective, of using a pediatrician in triage (PIT) in the emergency department (ED) and (2) assess the impact of a physician in triage on provider satisfaction. This was a prospective, controlled trial of PIT (intervention) versus conventional registered nurse-driven triage (control), at an urban, academic, tertiary level pediatric ED, which led to a cost-benefit analysis by looking at the effect that PIT has on length of stay (LOS) and thus on ED revenue. Provider satisfaction was assessed through surveys. During the 8-week study period, a total of 6579 patients were triaged: 3242 in the PIT group and 3337 in the control group. The 2 groups were similar in age, sex, admission rate, left-without-being-seen rate, and level of acuity. The mean LOS in the PIT group was 24.3 minutes shorter than in the control group. The costs of PIT seem to be increased and are not offset by savings; the net margin (total revenue minus costs) was $42,883 per year lower in the PIT than in the control group. Sensitivity analysis showed that if the LOS were reduced by more than 98.4 minutes, the cost savings would favor PIT. Most of the physicians and nurses (67%) reported that PIT facilitated their job. Placement of a PIT during periods of peak census resulted in shorter stay and notable provider satisfaction but at an incremental cost of $42,883 per year.

A cost-benefit/cost-effectiveness analysis of an unsanctioned supervised smoking facility in the Downtown Eastside of Vancouver, Canada.

Science.gov (United States)

Jozaghi, Ehsan

2014-11-13

Smoking crack involves the risk of transmitting diseases such as HIV and hepatitis C (HCV). The current study determines whether the formerly unsanctioned supervised smoking facility (SSF)-operated by the grassroot organization, Vancouver Area Network of Drug Users (VANDU) for the last few years-costs less than the costs incurred for health-care services as a direct consequence of not having such a program in Vancouver, Canada. The data pertaining to the attendance at the SSF was gathered in 2012-2013 by VANDU. By relying on this data, a mathematical model was employed to estimate the number of HCV infections prevented by the former facility in Vancouver's Downtown Eastside (DTES). The DTES SSF's benefit-cost ratio was conservatively estimated at 12.1:1 due to its low operating cost. The study used 70% and 90% initial pipe-sharing rates for sensitivity analysis. At 80% sharing rate, the marginal HCV cases prevented were determined to be 55 cases. Moreover, at 80% sharing rate, the marginal cost-effectiveness ratio ranges from $1,705 to $97,203. The results from both the baseline and sensitivity analysis demonstrated that the establishment of the SSF by VANDU on average had annually saved CAD$1.8 million dollars in taxpayer's money. Funding SSFs in Vancouver is an efficient and effective use of financial resources in the public health domain; therefore, Vancouver Coastal Health should actively participate in their establishment in order to reduce HCV and other blood-borne infections such as HIV within the non-injecting drug users.

The analysis of cost-effectiveness of implant and conventional fixed dental prosthesis.

Science.gov (United States)

Chun, June Sang; Har, Alix; Lim, Hyun-Pil; Lim, Hoi-Jeong

2016-02-01

This study conducted an analysis of cost-effectiveness of the implant and conventional fixed dental prosthesis (CFDP) from a single treatment perspective. The Markov model for cost-effectiveness analysis of the implant and CFDP was carried out over maximum 50 years. The probabilistic sensitivity analysis was performed by the 10,000 Monte-Carlo simulations, and cost-effectiveness acceptability curves (CEAC) were also presented. The results from meta-analysis studies were used to determine the survival rates and complication rates of the implant and CFDP. Data regarding the cost of each treatment method were collected from University Dental Hospital and Statistics Korea for 2013. Using the results of the patient satisfaction survey study, quality-adjusted prosthesis year (QAPY) of the implant and CFDP strategy was evaluated with annual discount rate. When only the direct cost was considered, implants were more cost-effective when the willingness to pay (WTP) was more than 10,000 won at 10(th) year after the treatment, and more cost-effective regardless of the WTP from 20(th) year after the prosthodontic treatment. When the indirect cost was added to the direct cost, implants were more cost-effective only when the WTP was more than 75,000 won at the 10(th) year after the prosthodontic treatment, more than 35,000 won at the 20(th) year after prosthodontic treatment. The CFDP was more cost-effective unless the WTP was more than 75,000 won at the 10(th) year after prosthodontic treatment. But the cost-effectivenss tendency changed from CFDP to implant as time passed.

Cost and cost-effectiveness analysis of a community mobilisation intervention to reduce intimate partner violence in Kampala, Uganda.

Science.gov (United States)

Michaels-Igbokwe, Christine; Abramsky, Tanya; Devries, Karen; Michau, Lori; Musuya, Tina; Watts, Charlotte

2016-02-29

Intimate partner violence (IPV) poses a major public health concern. To date there are few rigorous economic evaluations of interventions aimed at preventing IPV in low-income settings. This study provides a cost and cost effectiveness analysis of SASA!, a community mobilisation intervention to change social norms and prevent IPV. An economic evaluation alongside a cluster randomised controlled trial. Both financial and economic costs were collected retrospectively from the provider's perspective to generate total and unit cost estimates over four years of intervention programming. Univariate sensitivity analysis is conducted to estimate the impact of uncertainty in cost and outcome measures on results. The total cost of developing the SASA! Activist Kit is estimated as US$138,598. Total intervention costs over four years are estimated as US$553,252. The annual cost of supporting 351 activists to conduct SASA! activities was approximately US$389 per activist and the average cost per person reached in intervention communities was US$21 over the full course of the intervention, or US$5 annually. The primary trial outcome was past year experience of physical IPV with an estimated 1201 cases averted (90% CI: 97-2307 cases averted). The estimated cost per case of past year IPV averted was US$460. This study provides the first economic evaluation of a community mobilisation intervention aimed at preventing IPV. SASA! unit costs compare favourably with gender transformative interventions and support services for survivors of IPV. ClinicalTrials.gov # NCT00790959.

A feasibility and load sensitivity analysis of photovoltaic water pumping system with battery and diesel generator

International Nuclear Information System (INIS)

Muhsen, Dhiaa Halboot; Khatib, Tamer; Haider, Haider Tarish

2017-01-01

Highlights: • Feasibility and load sensitivity analysis is conducted for PVPS. • Battery and diesel generator are considered as supporting units to the system. • The configuration of the PV array and the initial status of the tank are important. • The COU is more sensitive to the capital cost of PV array than other components. • Increasing the maximum capacity of water storage tank is better storage and DG. - Abstract: In this paper, a feasibility and load sensitivity analysis is conducted for photovoltaic water pumping systems with storage device (battery) or diesel generator so as to obtain an optimal configuration that achieves a reliable system. The analysis is conducted based on techno-economic aspects, where the loss of load probability and life cycle cost are represented as technical and economic criteria, respectively. Various photovoltaic water pumping systems scenarios with initially full storage tank; battery and hybrid DG-PV energy source are proposed to analyze the feasibility of system. The result shows that the configuration of the PV array and the initial status of the storage tank are important variables to be considered. Moreover, the sensitivity of cost of unit for various PVPS components is studied. It is found that the cost of unit is more sensitive to the initial capital cost of photovoltaic array than other components. In this paper a standalone PV based pumping system with a PV array capacity of 2.4 kWp and a storage tank with a capacity of 80 m 3 was proposed an a optimum system. The system with the aforementioned configuration pumps an average hourly water volume of approximately 3.297 m 3 over one year with a unit of 0.05158 USD/m 3 . Moreover, according to results, increasing the maximum capacity of water storage tank is technically and economically better than supporting a photovoltaic water pumping systems with another energy source or extra storage device.

A cost sensitive inpatient bed reservation approach to reduce emergency department boarding times.

Science.gov (United States)

Qiu, Shanshan; Chinnam, Ratna Babu; Murat, Alper; Batarse, Bassam; Neemuchwala, Hakimuddin; Jordan, Will

2015-03-01

Emergency departments (ED) in hospitals are experiencing severe crowding and prolonged patient waiting times. A significant contributing factor is boarding delays where admitted patients are held in ED (occupying critical resources) until an inpatient bed is identified and readied in the admit wards. Recent research has suggested that if the hospital admissions of ED patients can be predicted during triage or soon after, then bed requests and preparations can be triggered early on to reduce patient boarding time. We propose a cost sensitive bed reservation policy that recommends optimal bed reservation times for patients. The policy relies on a classifier that estimates the probability that the ED patient will be admitted using the patient information collected and readily available at triage or right after. The policy is cost sensitive in that it accounts for costs associated with patient admission prediction misclassification as well as costs associated with incorrectly selecting the reservation time. Results from testing the proposed bed reservation policy using data from a VA Medical Center are very promising and suggest significant cost saving opportunities and reduced patient boarding times.

Cost-effectiveness analysis of combination therapies for visceral leishmaniasis in the Indian subcontinent.

Directory of Open Access Journals (Sweden)

Filip Meheus

2010-09-01

Full Text Available Visceral leishmaniasis is a systemic parasitic disease that is fatal unless treated. We assessed the cost and cost-effectiveness of alternative strategies for the treatment of visceral leishmaniasis in the Indian subcontinent. In particular we examined whether combination therapies are a cost-effective alternative compared to monotherapies.We assessed the cost-effectiveness of all possible mono- and combination therapies for the treatment of visceral leishmaniasis in the Indian subcontinent (India, Nepal and Bangladesh from a societal perspective using a decision analytical model based on a decision tree. Primary data collected in each country was combined with data from the literature and an expert poll (Delphi method. The cost per patient treated and average and incremental cost-effectiveness ratios expressed as cost per death averted were calculated. Extensive sensitivity analysis was done to evaluate the robustness of our estimations and conclusions. With a cost of US$92 per death averted, the combination miltefosine-paromomycin was the most cost-effective treatment strategy. The next best alternative was a combination of liposomal amphotericin B with paromomycin with an incremental cost-effectiveness of $652 per death averted. All other strategies were dominated with the exception of a single dose of 10mg per kg of liposomal amphotericin B. While strategies based on liposomal amphotericin B (AmBisome were found to be the most effective, its current drug cost of US$20 per vial resulted in a higher average cost-effectiveness. Sensitivity analysis showed the conclusion to be robust to variations in the input parameters over their plausible range.Combination treatments are a cost-effective alternative to current monotherapy for VL. Given their expected impact on the emergence of drug resistance, a switch to combination therapy should be considered once final results from clinical trials are available.

A cost-benefit analysis of power generation from commercial reinforced concrete solar chimney power plant

International Nuclear Information System (INIS)

Li, Weibing; Wei, Ping; Zhou, Xinping

2014-01-01

Highlights: • We develop an economic model different from related models. • We evaluate the initial investment cost of a plant built in northwest China. • We analyze the cost and benefit of a plant built in northwest China. • By the sensitivity analysis, we examine the sensitivity of TNPV to many parameters. - Abstract: This paper develops a model different from existing models to analyze the cost and benefit of a reinforced concrete solar chimney power plant (RCSCPP) built in northwest China. Based on the model and some assumptions for values of parameters, this work calculates total net present value (TNPV) and the minimum electricity price in each phase by dividing the whole service period into four phases. The results show that the minimum electricity price in the first phase is higher than the current market price of electricity, but the minimum prices in the other phases are far less than the current market price. The analysis indicates that huge advantages of the RCSCPP over coal-fired power plants can be embodied in phases 2–4. In addition, the sensitivity analysis performed in this paper discovers TNPV is very sensitive to changes in the solar electricity price and inflation rate, but responds only slightly to changes in carbon credits price, income tax rate and interest rate of loans. Our analysis predicts that RCSCPPs have very good application prospect. To encourage the development of RCSCPPs, the government should provide subsidy by setting higher electricity price in the first phase, then lower electricity price in the other phases

Methodology for cost analysis of film-based and filmless portable chest systems

Science.gov (United States)

Melson, David L.; Gauvain, Karen M.; Beardslee, Brian M.; Kraitsik, Michael J.; Burton, Larry; Blaine, G. James; Brink, Gary S.

1996-05-01

Many studies analyzing the costs of film-based and filmless radiology have focused on multi- modality, hospital-wide solutions. Yet due to the enormous cost of converting an entire large radiology department or hospital to a filmless environment all at once, institutions often choose to eliminate film one area at a time. Narrowing the focus of cost-analysis may be useful in making such decisions. This presentation will outline a methodology for analyzing the cost per exam of film-based and filmless solutions for providing portable chest exams to Intensive Care Units (ICUs). The methodology, unlike most in the literature, is based on parallel data collection from existing filmless and film-based ICUs, and is currently being utilized at our institution. Direct costs, taken from the perspective of the hospital, for portable computed radiography chest exams in one filmless and two film-based ICUs are identified. The major cost components are labor, equipment, materials, and storage. Methods for gathering and analyzing each of the cost components are discussed, including FTE-based and time-based labor analysis, incorporation of equipment depreciation, lease, and maintenance costs, and estimation of materials costs. Extrapolation of data from three ICUs to model hypothetical, hospital-wide film-based and filmless ICU imaging systems is described. Performance of sensitivity analysis on the filmless model to assess the impact of anticipated reductions in specific labor, equipment, and archiving costs is detailed. A number of indirect costs, which are not explicitly included in the analysis, are identified and discussed.

Decision-tree sensitivity analysis for cost-effectiveness of whole-body FDG PET in the management of patients with non-small-cell lung carcinoma in Japan

International Nuclear Information System (INIS)

Kosuda, Shigeru; Kobayashi, Hideo; Kusano, Shoichi; Ichihara, Kiyoshi; Watanabe, Masazumi

2002-01-01

Whole-body 2-fluoro-2-D-[ 18 F]deoxyglucose[FDG] positron emission tomography (WB-PET) may be more cost-effective than chest PET because WB-PET does not require conventional imaging (CI) for extrathoracic staging. The cost-effectiveness of WB-PET for the management of Japanese patients with non-small-cell lung carcinoma (NSCLC) was assessed. Decision-tree sensitivity analysis was designed, based on the two competing strategies of WB-PET vs. CI. WB-PET was assumed to have a sensitivity and specificity for detecting metastases, of 90% to 100% and CI of 80% to 90%. The prevalences of M1 disease were 34% and 20%. On thousand patients suspected of having NSCLC were simulated in each strategy. We surveyed the relevant literature for the choice of variables. Expected cost saving (CS) and expected life expectancy (LE) for NSCLC patients were calculated. The WB-PET strategy yielded an expected CS of $951 US to $1,493 US per patient and an expected LE of minus 0.0246 years to minus 0.0136 years per patient for the 71.4% NSCLC and 34% M1 disease prevalence at our hospital. PET avoided unnecessary bronchoscopies and thoracotomies for incurable and benign disease. Overall, the CS for each patient was $833 US to $2,010 US at NSCLC prevalences ranging from 10% to 90%. The LE of the WB-PET strategy was similar to that of the CI strategy. The CS and LE minimally varied in the two situations of 34% and 20% M1 disease prevalence. The introduction of a WB-PET strategy in place of CI for managing NSCLC patients is potentially cost-effective in Japan. (author)

Cost-Effectiveness Analysis of Stereotactic Body Radiation Therapy Compared With Radiofrequency Ablation for Inoperable Colorectal Liver Metastases

Energy Technology Data Exchange (ETDEWEB)

Kim, Hayeon, E-mail: kimh2@upmc.edu [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania (United States); Gill, Beant; Beriwal, Sushil; Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania (United States); Roberts, Mark S. [Department of Health Policy and Management, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania (United States); Smith, Kenneth J. [Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (United States)

2016-07-15

Purpose: To conduct a cost-effectiveness analysis to determine whether stereotactic body radiation therapy (SBRT) is a cost-effective therapy compared with radiofrequency ablation (RFA) for patients with unresectable colorectal cancer (CRC) liver metastases. Methods and Materials: A cost-effectiveness analysis was conducted using a Markov model and 1-month cycle over a lifetime horizon. Transition probabilities, quality of life utilities, and costs associated with SBRT and RFA were captured in the model on the basis of a comprehensive literature review and Medicare reimbursements in 2014. Strategies were compared using the incremental cost-effectiveness ratio, with effectiveness measured in quality-adjusted life years (QALYs). To account for model uncertainty, 1-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay threshold of $100,000 per QALY gained. Results: In base case analysis, treatment costs for 3 fractions of SBRT and 1 RFA procedure were $13,000 and $4397, respectively. Median survival was assumed the same for both strategies (25 months). The SBRT costs $8202 more than RFA while gaining 0.05 QALYs, resulting in an incremental cost-effectiveness ratio of $164,660 per QALY gained. In 1-way sensitivity analyses, results were most sensitive to variation of median survival from both treatments. Stereotactic body radiation therapy was economically reasonable if better survival was presumed (>1 month gain) or if used for large tumors (>4 cm). Conclusions: If equal survival is assumed, SBRT is not cost-effective compared with RFA for inoperable colorectal liver metastases. However, if better local control leads to small survival gains with SBRT, this strategy becomes cost-effective. Ideally, these results should be confirmed with prospective comparative data.

Cost-Effectiveness Analysis of Stereotactic Body Radiation Therapy Compared With Radiofrequency Ablation for Inoperable Colorectal Liver Metastases

International Nuclear Information System (INIS)

Kim, Hayeon; Gill, Beant; Beriwal, Sushil; Huq, M. Saiful; Roberts, Mark S.; Smith, Kenneth J.

2016-01-01

Purpose: To conduct a cost-effectiveness analysis to determine whether stereotactic body radiation therapy (SBRT) is a cost-effective therapy compared with radiofrequency ablation (RFA) for patients with unresectable colorectal cancer (CRC) liver metastases. Methods and Materials: A cost-effectiveness analysis was conducted using a Markov model and 1-month cycle over a lifetime horizon. Transition probabilities, quality of life utilities, and costs associated with SBRT and RFA were captured in the model on the basis of a comprehensive literature review and Medicare reimbursements in 2014. Strategies were compared using the incremental cost-effectiveness ratio, with effectiveness measured in quality-adjusted life years (QALYs). To account for model uncertainty, 1-way and probabilistic sensitivity analyses were performed. Strategies were evaluated with a willingness-to-pay threshold of $100,000 per QALY gained. Results: In base case analysis, treatment costs for 3 fractions of SBRT and 1 RFA procedure were $13,000 and $4397, respectively. Median survival was assumed the same for both strategies (25 months). The SBRT costs $8202 more than RFA while gaining 0.05 QALYs, resulting in an incremental cost-effectiveness ratio of $164,660 per QALY gained. In 1-way sensitivity analyses, results were most sensitive to variation of median survival from both treatments. Stereotactic body radiation therapy was economically reasonable if better survival was presumed (>1 month gain) or if used for large tumors (>4 cm). Conclusions: If equal survival is assumed, SBRT is not cost-effective compared with RFA for inoperable colorectal liver metastases. However, if better local control leads to small survival gains with SBRT, this strategy becomes cost-effective. Ideally, these results should be confirmed with prospective comparative data.

Cost-Utility Analysis: Sartorius Flap versus Negative Pressure Therapy for Infected Vascular Groin Graft Managment.

Science.gov (United States)

Chatterjee, Abhishek; Macarios, David; Griffin, Leah; Kosowski, Tomasz; Pyfer, Bryan J; Offodile, Anaeze C; Driscoll, Daniel; Maddali, Sirish; Attwood, John

2015-11-01

Sartorius flap coverage and adjunctive negative pressure wound therapy (NPWT) have been described in managing infected vascular groin grafts with varying cost and clinical success. We performed a cost-utility analysis comparing sartorius flap with NPWT in managing an infected vascular groin graft. A literature review compiling outcomes for sartorius flap and NPWT interventions was conducted from peer-reviewed journals in MEDLINE (PubMed) and EMBASE. Utility scores were derived from expert opinion and used to estimate quality-adjusted life years (QALYs). Medicare current procedure terminology and diagnosis-related groups codes were used to assess the costs for successful graft salvage with the associated complications. Incremental cost-effectiveness was assessed at $50,000/QALY, and both univariate and probabilistic sensitivity analyses were conducted to assess robustness of the conclusions. Thirty-two studies were used pooling 384 patients (234 sartorius flaps and 150 NPWT). NPWT had better clinical outcomes (86.7% success rate, 0.9% minor complication rate, and 13.3% major complication rate) than sartorius flap (81.6% success rate, 8.0% minor complication rate, and 18.4% major complication rate). NPWT was less costly ($12,366 versus $23,516) and slightly more effective (12.06 QALY versus 12.05 QALY) compared with sartorius flap. Sensitivity analyses confirmed the robustness of the base case findings; NPWT was either cost-effective at $50,000/QALY or dominated sartorius flap in 81.6% of all probabilistic sensitivity analyses. In our cost-utility analysis, use of adjunctive NPWT, along with debridement and antibiotic treatment, for managing infected vascular groin graft wounds was found to be a more cost-effective option when compared with sartorius flaps.

Cost-Effectiveness of Endovascular Stroke Therapy: A Patient Subgroup Analysis From a US Healthcare Perspective.

Science.gov (United States)

Kunz, Wolfgang G; Hunink, M G Myriam; Sommer, Wieland H; Beyer, Sebastian E; Meinel, Felix G; Dorn, Franziska; Wirth, Stefan; Reiser, Maximilian F; Ertl-Wagner, Birgit; Thierfelder, Kolja M

2016-11-01

Endovascular therapy in addition to standard care (EVT+SC) has been demonstrated to be more effective than SC in acute ischemic large vessel occlusion stroke. Our aim was to determine the cost-effectiveness of EVT+SC depending on patients' initial National Institutes of Health Stroke Scale (NIHSS) score, time from symptom onset, Alberta Stroke Program Early CT Score (ASPECTS), and occlusion location. A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with both strategies applied in a US setting. Model input parameters were obtained from the literature, including recently pooled outcome data of 5 randomized controlled trials (ESCAPE [Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke], EXTEND-IA [Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial], MR CLEAN [Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands], REVASCAT [Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within 8 Hours of Symptom Onset], and SWIFT PRIME [Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment]). Probabilistic sensitivity analysis was performed to estimate uncertainty of the model results. Net monetary benefits, incremental costs, incremental effectiveness, and incremental cost-effectiveness ratios were derived from the probabilistic sensitivity analysis. The willingness-to-pay was set to $50 000/QALY. Overall, EVT+SC was cost-effective compared with SC (incremental cost: $4938, incremental effectiveness: 1.59 QALYs, and incremental cost-effectiveness ratio: $3110/QALY) in 100% of simulations. In all patient subgroups, EVT+SC led to gained QALYs (range: 0.47-2.12), and mean incremental cost-effectiveness ratios were considered cost

Cross Validation Through Two-Dimensional Solution Surface for Cost-Sensitive SVM.

Science.gov (United States)

Gu, Bin; Sheng, Victor S; Tay, Keng Yeow; Romano, Walter; Li, Shuo

2017-06-01

Model selection plays an important role in cost-sensitive SVM (CS-SVM). It has been proven that the global minimum cross validation (CV) error can be efficiently computed based on the solution path for one parameter learning problems. However, it is a challenge to obtain the global minimum CV error for CS-SVM based on one-dimensional solution path and traditional grid search, because CS-SVM is with two regularization parameters. In this paper, we propose a solution and error surfaces based CV approach (CV-SES). More specifically, we first compute a two-dimensional solution surface for CS-SVM based on a bi-parameter space partition algorithm, which can fit solutions of CS-SVM for all values of both regularization parameters. Then, we compute a two-dimensional validation error surface for each CV fold, which can fit validation errors of CS-SVM for all values of both regularization parameters. Finally, we obtain the CV error surface by superposing K validation error surfaces, which can find the global minimum CV error of CS-SVM. Experiments are conducted on seven datasets for cost sensitive learning and on four datasets for imbalanced learning. Experimental results not only show that our proposed CV-SES has a better generalization ability than CS-SVM with various hybrids between grid search and solution path methods, and than recent proposed cost-sensitive hinge loss SVM with three-dimensional grid search, but also show that CV-SES uses less running time.

Sensitivity Analysis of Unsteady Flow Fields and Impact of Measurement Strategy

Directory of Open Access Journals (Sweden)

Takashi Misaka

2014-01-01

Full Text Available Difficulty of data assimilation arises from a large difference between the sizes of a state vector to be determined, that is, the number of spatiotemporal mesh points of a discretized numerical model and a measurement vector, that is, the amount of measurement data. Flow variables on a large number of mesh points are hardly defined by spatiotemporally limited measurements, which poses an underdetermined problem. In this study we conduct the sensitivity analysis of two- and three-dimensional vortical flow fields within a framework of data assimilation. The impact of measurement strategy, which is evaluated by the sensitivity of the 4D-Var cost function with respect to measurements, is investigated to effectively determine a flow field by limited measurements. The assimilation experiment shows that the error defined by the difference between the reference and assimilated flow fields is reduced by using the sensitivity information to locate the limited number of measurement points. To conduct data assimilation for a long time period, the 4D-Var data assimilation and the sensitivity analysis are repeated with a short assimilation window.

Cost Analysis of Poor Quality Using a Software Simulation

Directory of Open Access Journals (Sweden)

Jana Fabianová

2017-02-01

Full Text Available The issues of quality, cost of poor quality and factors affecting quality are crucial to maintaining a competitiveness regarding to business activities. Use of software applications and computer simulation enables more effective quality management. Simulation tools offer incorporating the variability of more variables in experiments and evaluating their common impact on the final output. The article presents a case study focused on the possibility of using computer simulation Monte Carlo in the field of quality management. Two approaches for determining the cost of poor quality are introduced here. One from retrospective scope of view, where the cost of poor quality and production process are calculated based on historical data. The second approach uses the probabilistic characteristics of the input variables by means of simulation, and reflects as a perspective view of the costs of poor quality. Simulation output in the form of a tornado and sensitivity charts complement the risk analysis.

Regional and parametric sensitivity analysis of Sobol' indices

International Nuclear Information System (INIS)

Wei, Pengfei; Lu, Zhenzhou; Song, Jingwen

2015-01-01

Nowadays, utilizing the Monte Carlo estimators for variance-based sensitivity analysis has gained sufficient popularity in many research fields. These estimators are usually based on n+2 sample matrices well designed for computing both the main and total effect indices, where n is the input dimension. The aim of this paper is to use such n+2 sample matrices to investigate how the main and total effect indices change when the uncertainty of the model inputs are reduced. For this purpose, the regional main and total effect functions are defined for measuring the changes on the main and total effect indices when the distribution range of one input is reduced, and the parametric main and total effect functions are introduced to quantify the residual main and total effect indices due to the reduced variance of one input. Monte Carlo estimators are derived for all the developed sensitivity concepts based on the n+2 samples matrices originally used for computing the main and total effect indices, thus no extra computational cost is introduced. The Ishigami function, a nonlinear model and a planar ten-bar structure are utilized for illustrating the developed sensitivity concepts, and for demonstrating the efficiency and accuracy of the derived Monte Carlo estimators. - Highlights: • The regional main and total effect functions are developed. • The parametric main and total effect functions are introduced. • The proposed sensitivity functions are all generalizations of Sobol' indices. • The Monte Carlo estimators are derived for the four sensitivity functions. • The computational cost of the estimators is the same as that of Sobol' indices

Cost-effectiveness analysis of left atrial appendage occlusion compared with pharmacological strategies for stroke prevention in atrial fibrillation.

Science.gov (United States)

Lee, Vivian Wing-Yan; Tsai, Ronald Bing-Ching; Chow, Ines Hang-Iao; Yan, Bryan Ping-Yen; Kaya, Mehmet Gungor; Park, Jai-Wun; Lam, Yat-Yin

2016-08-31

Transcatheter left atrial appendage occlusion (LAAO) is a promising therapy for stroke prophylaxis in non-valvular atrial fibrillation (NVAF) but its cost-effectiveness remains understudied. This study evaluated the cost-effectiveness of LAAO for stroke prophylaxis in NVAF. A Markov decision analytic model was used to compare the cost-effectiveness of LAAO with 7 pharmacological strategies: aspirin alone, clopidogrel plus aspirin, warfarin, dabigatran 110 mg, dabigatran 150 mg, apixaban, and rivaroxaban. Outcome measures included quality-adjusted life years (QALYs), lifetime costs and incremental cost-effectiveness ratios (ICERs). Base-case data were derived from ACTIVE, RE-LY, ARISTOTLE, ROCKET-AF, PROTECT-AF and PREVAIL trials. One-way sensitivity analysis varied by CHADS2 score, HAS-BLED score, time horizons, and LAAO costs; and probabilistic sensitivity analysis using 10,000 Monte Carlo simulations was conducted to assess parameter uncertainty. LAAO was considered cost-effective compared with aspirin, clopidogrel plus aspirin, and warfarin, with ICER of US$5,115, $2,447, and $6,298 per QALY gained, respectively. LAAO was dominant (i.e. less costly but more effective) compared to other strategies. Sensitivity analysis demonstrated favorable ICERs of LAAO against other strategies in varied CHADS2 score, HAS-BLED score, time horizons (5 to 15 years) and LAAO costs. LAAO was cost-effective in 86.24 % of 10,000 simulations using a threshold of US$50,000/QALY. Transcatheter LAAO is cost-effective for prevention of stroke in NVAF compared with 7 pharmacological strategies. The transcatheter left atrial appendage occlusion (LAAO) is considered cost-effective against the standard 7 oral pharmacological strategies including acetylsalicylic acid (ASA) alone, clopidogrel plus ASA, warfarin, dabigatran 110 mg, dabigatran 150 mg, apixaban, and rivaroxaban for stroke prophylaxis in non-valvular atrial fibrillation management.

Cost-effectiveness analysis of colon cancer treatments from MOSIAC and No. 16968 trials.

Science.gov (United States)

Wen, Feng; Yao, Ke; Du, Ze-Dong; He, Xiao-Feng; Zhang, Peng-Fei; Tang, Rui-Lei; Li, Qiu

2014-12-21

To compare XELOX and FOLFOX4 as colon cancer adjuvant chemotherapy based on MOSAIC and No. 16968 trails from Chinese cost-effectiveness perspective. A decision-analytic Markov model was developed to compare the FOLFOX4 and XELOX regimens based MOSAIC and No. 16968 trial. Five states were included in our Markov model: well (state 1), minor toxicity (state 2), major toxicity (state 3), quitting adjuvant chemotherapy (state 4), and death due to adjuvant chemotherapy (state 5). Transitions among the 5 states were assumed to be Markovian. Costs were calculated from the perspective of the Chinese health-care payer. The utility data were taken from published studies. Sensitivity analyses were used to explore the impact of uncertainty factors in this cost-effectiveness analysis. Total direct costs of FOLFOX4 and XELOX per patient were $19884.96 ± 4280.30 and $18113.25 ± 3122.20, respectively. The total fees related to adverse events per patient during the entire treatment were $204.75 ± 16.80 for the XELOX group, and $873.72 ± 27.60 for the FOLFOX4 group, and the costs for travel and absenteeism per patient were $18495.00 for the XELOX group and $21,352.68 for the FOLFOX4 group. The base-case analysis showed that FOLFOX4 was estimated to produce an additional 0.06 in quality adjusted life years (QALYs) at an additional cost of $3950.47 when compared to the XELOX regimen over the model time horizon. The cost per QALY gained was $8047.30 in the XELOX group, which was $900.98 less than in the FOLFOX4 group ($8948.28). The one way sensitivity analysis demonstrated that the utility for the well state and minor toxicity state greatly influenced the incremental cost-effectiveness ratio of FOLFOX4. In term of cost-comparison, XELOX is expected to dominate FOLFOX4 regimes; Therefore, XELOX provides a more cost-effective adjuvant chemotherapy for colon cancer patients in China.

A Cost-effectiveness Analysis of Early vs Late Tracheostomy.

Science.gov (United States)

Liu, C Carrie; Rudmik, Luke

2016-10-01

The timing of tracheostomy in critically ill patients requiring mechanical ventilation is controversial. An important consideration that is currently missing in the literature is an evaluation of the economic impact of an early tracheostomy strategy vs a late tracheostomy strategy. To evaluate the cost-effectiveness of the early tracheostomy strategy vs the late tracheostomy strategy. This economic analysis was performed using a decision tree model with a 90-day time horizon. The economic perspective was that of the US health care third-party payer. The primary outcome was the incremental cost per tracheostomy avoided. Probabilities were obtained from meta-analyses of randomized clinical trials. Costs were obtained from the published literature and the Healthcare Cost and Utilization Project database. A multivariate probabilistic sensitivity analysis was performed to account for uncertainty surrounding mean values used in the reference case. The reference case demonstrated that the cost of the late tracheostomy strategy was $45 943.81 for 0.36 of effectiveness. The cost of the early tracheostomy strategy was $31 979.12 for 0.19 of effectiveness. The incremental cost-effectiveness ratio for the late tracheostomy strategy compared with the early tracheostomy strategy was $82 145.24 per tracheostomy avoided. With a willingness-to-pay threshold of $50 000, the early tracheostomy strategy is cost-effective with 56% certainty. The adaptation of an early vs a late tracheostomy strategy depends on the priorities of the decision-maker. Up to a willingness-to-pay threshold of $80 000 per tracheostomy avoided, the early tracheostomy strategy has a higher probability of being the more cost-effective intervention.

Use of external cost assessment and multi-criteria decision analysis for comparative evaluation of options for electricity supply

International Nuclear Information System (INIS)

Hirschberg, Stefan; Dones, Roberto; Gantner, Urs

2000-01-01

This paper addresses external cost and multi-criteria analyses carried out for selected future electricity generating systems of interest under the Swiss. conditions. The external cost estimates are based on an application of the 'impact pathway approach', enriched by earlier experience from extensive Life Cycle Assessment (LCA). The estimated total costs, i.e. the sum of internal and external costs may serve as a measure of economic and environmental efficiency of energy systems. The multi-criteria approach allows a more explicit consideration of the social dimension, highly important for the decision process. The applications of multi-criteria analysis illustrate the sensitivity of the results to a range of preferences expressed in the energy debate. Certain patterns in systems ranking can be observed in spite of these sensitivities. Both total cost assessment and multi-criteria analysis are found to be useful, complementary instruments to support the decision process. (author)

Mixed kernel function support vector regression for global sensitivity analysis

Science.gov (United States)

Cheng, Kai; Lu, Zhenzhou; Wei, Yuhao; Shi, Yan; Zhou, Yicheng

2017-11-01

Global sensitivity analysis (GSA) plays an important role in exploring the respective effects of input variables on an assigned output response. Amongst the wide sensitivity analyses in literature, the Sobol indices have attracted much attention since they can provide accurate information for most models. In this paper, a mixed kernel function (MKF) based support vector regression (SVR) model is employed to evaluate the Sobol indices at low computational cost. By the proposed derivation, the estimation of the Sobol indices can be obtained by post-processing the coefficients of the SVR meta-model. The MKF is constituted by the orthogonal polynomials kernel function and Gaussian radial basis kernel function, thus the MKF possesses both the global characteristic advantage of the polynomials kernel function and the local characteristic advantage of the Gaussian radial basis kernel function. The proposed approach is suitable for high-dimensional and non-linear problems. Performance of the proposed approach is validated by various analytical functions and compared with the popular polynomial chaos expansion (PCE). Results demonstrate that the proposed approach is an efficient method for global sensitivity analysis.

Cost-Utility Analysis of Depot Atypical Antipsychotics for Chronic Schizophrenia in Croatia.

Science.gov (United States)

Jukic, Vlado; Jakovljevic, Miro; Filipcic, Igor; Herceg, Miroslav; Silic, Ante; Tomljanovic, Tatjana; Zilbershtein, Roman; Jensen, Rasmus C D; Hemels, Michiel E H; Einarson, Thomas R

As a nation with a developing economy, Croatia is faced with making choices between pharmaceutical products, including depot injectable antipsychotics. We conducted a pharmacoeconomic analysis to determine the cost-effectiveness of atypical depots in Croatia. A 1-year decision-analytic framework modeled drug use. We determined the average direct cost to the Croatian Institute for Health Insurance of using depot formulations of paliperidone palmitate long-acting injectable (PP-LAI), risperidone LAI (RIS-LAI), or olanzapine LAI (OLZ-LAI). An expert panel plus literature-derived clinical rates populated the core model, along with costs adjusted to 2012 by using the Croatian consumer price index. Clinical outcomes included quality-adjusted life-years, hospitalization rates, emergency room treatment rates, and relapse days. Robustness of results was examined with one-way sensitivity analyses on important inputs; overall, all inputs were varied over 10,000 simulations in a Monte Carlo analysis. Costs (quality-adjusted life-years) per patient were €5061 (0.817) for PP-LAI, €5168 (0.807) for RIS-LAI, and €6410 (0.812) for OLZ-LAI. PP-LAI had the fewest relapse days, emergency room visits, and hospitalizations. Results were sensitive against RIS-LAI with respect to drug costs and adherence rates, but were generally robust overall, dominating OLZ-LAI in 77.3% and RIS-LAI in 56.8% of the simulations. PP-LAI dominated the other drugs because it had the lowest cost and best clinical outcomes. Compared with depots of olanzapine and risperidone and oral olanzapine, PP-LAI was the cost-effective atypical LAI for treating chronic schizophrenia in Croatia. Using depot paliperidone in place of either olanzapine or risperidone would reduce the overall costs of caring for these patients. Copyright © 2013, International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc.

Cost benefit analysis of recycling nuclear fuel cycle in Korea

International Nuclear Information System (INIS)

Lee, Jewhan; Chang, Soonheung

2012-01-01

Nuclear power has become an essential part of electricity generation to meet the continuous growth of electricity demand. The importance if nuclear waste management has been the main issue since the beginning of nuclear history. The recycling nuclear fuel cycle includes the fast reactor, which can burn the nuclear wastes, and the pyro-processing technology, which can reprocess the spent nuclear fuel. In this study, a methodology using Linear Programming (LP) is employed to evaluate the cost and benefits of introducing the recycling strategy and thus, to see the competitiveness of recycling fuel cycle. The LP optimization involves tradeoffs between the fast reactor capital cost with pyro-processing cost premiums and the total system uranium price with spent nuclear fuel management cost premiums. With the help of LP and sensitivity analysis, the effect of important parameters is presented as well as the target values for each cost and price of key factors

MOVES regional level sensitivity analysis

Science.gov (United States)

2012-01-01

The MOVES Regional Level Sensitivity Analysis was conducted to increase understanding of the operations of the MOVES Model in regional emissions analysis and to highlight the following: : the relative sensitivity of selected MOVES Model input paramet...

Cost-effectiveness analysis of trastuzumab in the adjuvant setting for treatment of HER2-positive breast cancer.

Science.gov (United States)

Garrison, Louis P; Lubeck, Deborah; Lalla, Deepa; Paton, Virginia; Dueck, Amylou; Perez, Edith A

2007-08-01

Adding trastuzumab to adjuvant chemotherapy provides significant clinical benefit in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. A cost-effectiveness analysis was performed to assess clinical and economic implications of adding trastuzumab to adjuvant chemotherapy, based upon joint analysis of NSABP B-31 and NCCTG N9831 trials. A Markov model with 4 health states was used to estimate the cost utility for a 50-year-old woman on the basis of trial results through 4 years and estimates of long-term recurrence and death based on a meta-analysis of trials. From 6 years onward, rates of recurrence and death were assumed to be the same in both trastuzumab and chemotherapy-only arms. Incremental costs were estimated for diagnostic and treatment-related costs. Analyses were from payer and societal perspectives, and these analyses were projected to lifetime and 20-year horizons. Over a lifetime, the projected cost of trastuzumab per quality-adjusted life year (QALY; discount rate 3%) gained was 26,417 dollars (range 9,104 dollars-69,340 dollars under multiway sensitivity analysis). Discounted incremental lifetime cost was 44,923 dollars, and projected life expectancy was 3 years longer for patients who received trastuzumab (19.4 years vs 16.4 years). During a 20-year horizon, the projected cost of adding trastuzumab to chemotherapy was 34,201 dollars per QALY gained. Key cost-effectiveness drivers were discount rate, trastuzumab price, and probability of metastasis. The cost-effectiveness result was robust to sensitivity analysis. Trastuzumab for adjuvant treatment of early stage breast cancer was projected to be cost effective over a lifetime horizon, achieving a cost-effectiveness ratio below that of many widely accepted oncology treatments. (c) 2007 American Cancer Society.

Cost effectiveness analysis comparing repetitive transcranial magnetic stimulation to antidepressant medications after a first treatment failure for major depressive disorder in newly diagnosed patients - A lifetime analysis.

Science.gov (United States)

Voigt, Jeffrey; Carpenter, Linda; Leuchter, Andrew

2017-01-01

Repetitive Transcranial Magnetic Stimulation (rTMS) commonly is used for the treatment of Major Depressive Disorder (MDD) after patients have failed to benefit from trials of multiple antidepressant medications. No analysis to date has examined the cost-effectiveness of rTMS used earlier in the course of treatment and over a patients' lifetime. We used lifetime Markov simulation modeling to compare the direct costs and quality adjusted life years (QALYs) of rTMS and medication therapy in patients with newly diagnosed MDD (ages 20-59) who had failed to benefit from one pharmacotherapy trial. Patients' life expectancies, rates of response and remission, and quality of life outcomes were derived from the literature, and treatment costs were based upon published Medicare reimbursement data. Baseline costs, aggregate per year quality of life assessments (QALYs), Monte Carlo simulation, tornado analysis, assessment of dominance, and one way sensitivity analysis were also performed. The discount rate applied was 3%. Lifetime direct treatment costs, and QALYs identified rTMS as the dominant therapy compared to antidepressant medications (i.e., lower costs with better outcomes) in all age ranges, with costs/improved QALYs ranging from $2,952/0.32 (older patients) to $11,140/0.43 (younger patients). One-way sensitivity analysis demonstrated that the model was most sensitive to the input variables of cost per rTMS session, monthly prescription drug cost, and the number of rTMS sessions per year. rTMS was identified as the dominant therapy compared to antidepressant medication trials over the life of the patient across the lifespan of adults with MDD, given current costs of treatment. These models support the use of rTMS after a single failed antidepressant medication trial versus further attempts at medication treatment in adults with MDD.

Cost effectiveness analysis comparing repetitive transcranial magnetic stimulation to antidepressant medications after a first treatment failure for major depressive disorder in newly diagnosed patients - A lifetime analysis.

Directory of Open Access Journals (Sweden)

Jeffrey Voigt

Full Text Available Repetitive Transcranial Magnetic Stimulation (rTMS commonly is used for the treatment of Major Depressive Disorder (MDD after patients have failed to benefit from trials of multiple antidepressant medications. No analysis to date has examined the cost-effectiveness of rTMS used earlier in the course of treatment and over a patients' lifetime.We used lifetime Markov simulation modeling to compare the direct costs and quality adjusted life years (QALYs of rTMS and medication therapy in patients with newly diagnosed MDD (ages 20-59 who had failed to benefit from one pharmacotherapy trial. Patients' life expectancies, rates of response and remission, and quality of life outcomes were derived from the literature, and treatment costs were based upon published Medicare reimbursement data. Baseline costs, aggregate per year quality of life assessments (QALYs, Monte Carlo simulation, tornado analysis, assessment of dominance, and one way sensitivity analysis were also performed. The discount rate applied was 3%.Lifetime direct treatment costs, and QALYs identified rTMS as the dominant therapy compared to antidepressant medications (i.e., lower costs with better outcomes in all age ranges, with costs/improved QALYs ranging from $2,952/0.32 (older patients to $11,140/0.43 (younger patients. One-way sensitivity analysis demonstrated that the model was most sensitive to the input variables of cost per rTMS session, monthly prescription drug cost, and the number of rTMS sessions per year.rTMS was identified as the dominant therapy compared to antidepressant medication trials over the life of the patient across the lifespan of adults with MDD, given current costs of treatment. These models support the use of rTMS after a single failed antidepressant medication trial versus further attempts at medication treatment in adults with MDD.

An analysis of decommissioning costs

International Nuclear Information System (INIS)

Teunckens, L.; Loeschhorn, U.; Yanagihara, S.; Wren, G.; Menon, S.

1992-01-01

Within the OECD/NEA Cooperative Programme on Decommissioning a Task Group was set up early in 1989 to identify the reasons for the large variations in decommissioning cost estimates. The Task Group gathered cost data from 12 of the 14 projects in the Programme to form the basis of their analysis. They included reactors being decommissioned to various stages as well as fuel cycle facilities. The projects were divided into groups of projects with similar characteristics ('models') to facilitate the analysis of the cost distribution in each group of projects and the cost data was progressively refined by a dialogue between the Task Group and the project managers. A comparative analysis was then performed and project specific discrepancies were identified. The Task Group's report is summarized on the results of the comparative analysis as well as the lessons learnt by the Task Group in the acquisition and analysis of cost data from international decommissioning projects. (author) 5 tabs

Ethics and Cost-Benefit Analysis

DEFF Research Database (Denmark)

Arler, Finn

The purpose of this research report is threefold. Firstly, the author traces the origins and justification of cost-benefit analysis in moral and political philosophy. Secondly, he explain some of the basic features of cost-benefit analysis as a planning tool in a step-bystep presentation. Thirdly......, he presents and discusses some of the main ethical difficulties related to the use of cost-benefit analysis as a planning tool....

Example-Dependent Cost-Sensitive Classification with Applications in Financial Risk Modeling and Marketing Analytics

OpenAIRE

Correa Bahnsen, Alejandro

2015-01-01

Several real-world binary classification problems are example-dependent cost-sensitive in nature, where the costs due to misclassification vary between examples and not only within classes. However, standard binary classification methods do not take these costs into account, and assume a constant cost of misclassification errors. This approach is not realistic in many real-world applications. For example in credit card fraud detection, failing to detect a fraudulent transaction may have an ec...

Uncertainty and sensitivity analyses of ballast life-cycle cost and payback period

OpenAIRE

Mcmahon, James E.

2000-01-01

The paper introduces an innovative methology for evaluating the relative significance of energy-efficient technologies applied to fluorescent lamp ballasts. The method involves replacing the point estimates of life cycle cost of the ballasts with uncertainty distributions reflecting the whole spectrum of possible costs, and the assessed probability associated with each value. The results of uncertainty and sensitivity analyses will help analysts reduce effort in data collection and carry on a...

Cost-effectiveness analysis of universal maternal immunization with tetanus-diphtheria-acellular pertussis (Tdap) vaccine in Brazil.

Science.gov (United States)

Sartori, Ana Marli Christovam; de Soárez, Patrícia Coelho; Fernandes, Eder Gatti; Gryninger, Ligia Castellon Figueiredo; Viscondi, Juliana Yukari Kodaira; Novaes, Hillegonda Maria Dutilh

2016-03-18

Pertussis incidence has increased significantly in Brazil since 2011, despite high coverage of whole-cell pertussis containing vaccines in childhood. Infants cost-effectiveness of introducing universal maternal vaccination with tetanus-diphtheria-acellular pertussis vaccine (Tdap) into the National Immunization Program in Brazil. Economic evaluation using a decision tree model comparing two strategies: (1) universal vaccination with one dose of Tdap in the third trimester of pregnancy and (2) current practice (no pertussis maternal vaccination), from the perspective of the health system and society. An annual cohort of newborns representing the number of vaccinated pregnant women were followed for one year. Vaccine efficacy were based on literature review. Epidemiological, healthcare resource utilization and cost estimates were based on local data retrieved from Brazilian Health Information Systems. Costs of epidemiological investigation and treatment of contacts of cases were included in the analysis. No discount rate was applied to costs and benefits, as the temporal horizon was one year. Primary outcome was cost per life year saved (LYS). Univariate and best- and worst-case scenarios sensitivity analysis were performed. Maternal vaccination of one annual cohort, with vaccine effectiveness of 78%, and vaccine cost of USD$12.39 per dose, would avoid 661 cases and 24 infant deaths of pertussis, save 1800 years of life and cost USD$28,942,808 and USD$29,002,947, respectively, from the health system and societal perspective. The universal immunization would result in ICERs of USD$15,608 and USD$15,590 per LYS, from the health system and societal perspective, respectively. In sensitivity analysis, the ICER was most sensitive to discounting of life years saved, variation in case-fatality, disease incidence, vaccine cost, and vaccine effectiveness. The results indicate that universal maternal immunization with Tdap is a cost-effective intervention for preventing

Analytical methods for large-scale sensitivity analysis using GRESS [GRadient Enhanced Software System] and ADGEN [Automated Adjoint Generator

International Nuclear Information System (INIS)

Pin, F.G.

1988-04-01

Sensitivity analysis is an established methodology used by researchers in almost every field to gain essential insight in design and modeling studies and in performance assessments of complex systems. Conventional sensitivity analysis methodologies, however, have not enjoyed the widespread use they deserve considering the wealth of information they can provide, partly because of their prohibitive cost or the large initial analytical investment they require. Automated systems have recently been developed at ORNL to eliminate these drawbacks. Compilers such as GRESS and ADGEN now allow automatic and cost effective calculation of sensitivities in FORTRAN computer codes. In this paper, these and other related tools are described and their impact and applicability in the general areas of modeling, performance assessment and decision making for radioactive waste isolation problems are discussed. 7 refs., 2 figs

Sensitivity analysis approaches applied to systems biology models.

Science.gov (United States)

Zi, Z

2011-11-01

With the rising application of systems biology, sensitivity analysis methods have been widely applied to study the biological systems, including metabolic networks, signalling pathways and genetic circuits. Sensitivity analysis can provide valuable insights about how robust the biological responses are with respect to the changes of biological parameters and which model inputs are the key factors that affect the model outputs. In addition, sensitivity analysis is valuable for guiding experimental analysis, model reduction and parameter estimation. Local and global sensitivity analysis approaches are the two types of sensitivity analysis that are commonly applied in systems biology. Local sensitivity analysis is a classic method that studies the impact of small perturbations on the model outputs. On the other hand, global sensitivity analysis approaches have been applied to understand how the model outputs are affected by large variations of the model input parameters. In this review, the author introduces the basic concepts of sensitivity analysis approaches applied to systems biology models. Moreover, the author discusses the advantages and disadvantages of different sensitivity analysis methods, how to choose a proper sensitivity analysis approach, the available sensitivity analysis tools for systems biology models and the caveats in the interpretation of sensitivity analysis results.

Sensitivity Analysis Without Assumptions.

Science.gov (United States)

Ding, Peng; VanderWeele, Tyler J

2016-05-01

Unmeasured confounding may undermine the validity of causal inference with observational studies. Sensitivity analysis provides an attractive way to partially circumvent this issue by assessing the potential influence of unmeasured confounding on causal conclusions. However, previous sensitivity analysis approaches often make strong and untestable assumptions such as having an unmeasured confounder that is binary, or having no interaction between the effects of the exposure and the confounder on the outcome, or having only one unmeasured confounder. Without imposing any assumptions on the unmeasured confounder or confounders, we derive a bounding factor and a sharp inequality such that the sensitivity analysis parameters must satisfy the inequality if an unmeasured confounder is to explain away the observed effect estimate or reduce it to a particular level. Our approach is easy to implement and involves only two sensitivity parameters. Surprisingly, our bounding factor, which makes no simplifying assumptions, is no more conservative than a number of previous sensitivity analysis techniques that do make assumptions. Our new bounding factor implies not only the traditional Cornfield conditions that both the relative risk of the exposure on the confounder and that of the confounder on the outcome must satisfy but also a high threshold that the maximum of these relative risks must satisfy. Furthermore, this new bounding factor can be viewed as a measure of the strength of confounding between the exposure and the outcome induced by a confounder.

Sensitivity analysis of critical experiment with direct perturbation compared to TSUNAMI-3D sensitivity analysis

International Nuclear Information System (INIS)

Barber, A. D.; Busch, R.

2009-01-01

The goal of this work is to obtain sensitivities from direct uncertainty analysis calculation and correlate those calculated values with the sensitivities produced from TSUNAMI-3D (Tools for Sensitivity and Uncertainty Analysis Methodology Implementation in Three Dimensions). A full sensitivity analysis is performed on a critical experiment to determine the overall uncertainty of the experiment. Small perturbation calculations are performed for all known uncertainties to obtain the total uncertainty of the experiment. The results from a critical experiment are only known as well as the geometric and material properties. The goal of this relationship is to simplify the uncertainty quantification process in assessing a critical experiment, while still considering all of the important parameters. (authors)

Sensitivity analysis in multi-parameter probabilistic systems

International Nuclear Information System (INIS)

Walker, J.R.

1987-01-01

Probabilistic methods involving the use of multi-parameter Monte Carlo analysis can be applied to a wide range of engineering systems. The output from the Monte Carlo analysis is a probabilistic estimate of the system consequence, which can vary spatially and temporally. Sensitivity analysis aims to examine how the output consequence is influenced by the input parameter values. Sensitivity analysis provides the necessary information so that the engineering properties of the system can be optimized. This report details a package of sensitivity analysis techniques that together form an integrated methodology for the sensitivity analysis of probabilistic systems. The techniques have known confidence limits and can be applied to a wide range of engineering problems. The sensitivity analysis methodology is illustrated by performing the sensitivity analysis of the MCROC rock microcracking model

An Efficient Cost-Sensitive Feature Selection Using Chaos Genetic Algorithm for Class Imbalance Problem

Directory of Open Access Journals (Sweden)

Jing Bian

2016-01-01

Full Text Available In the era of big data, feature selection is an essential process in machine learning. Although the class imbalance problem has recently attracted a great deal of attention, little effort has been undertaken to develop feature selection techniques. In addition, most applications involving feature selection focus on classification accuracy but not cost, although costs are important. To cope with imbalance problems, we developed a cost-sensitive feature selection algorithm that adds the cost-based evaluation function of a filter feature selection using a chaos genetic algorithm, referred to as CSFSG. The evaluation function considers both feature-acquiring costs (test costs and misclassification costs in the field of network security, thereby weakening the influence of many instances from the majority of classes in large-scale datasets. The CSFSG algorithm reduces the total cost of feature selection and trades off both factors. The behavior of the CSFSG algorithm is tested on a large-scale dataset of network security, using two kinds of classifiers: C4.5 and k-nearest neighbor (KNN. The results of the experimental research show that the approach is efficient and able to effectively improve classification accuracy and to decrease classification time. In addition, the results of our method are more promising than the results of other cost-sensitive feature selection algorithms.

Financial Profitability and Sensitivity Analysis of Palm Oil Plantation in Indonesia

Directory of Open Access Journals (Sweden)

Tereza Svatoňová

2015-01-01

Full Text Available Oil palm cultivation in Indonesia is increasing. This study investigates the financial and economic aspects of establishing an oil palm plantation using data collected in 2014. The financial case study is undertaken from the perspective of company in North Sumatra, Indonesia. A spreadsheet model was used to develop and calculate the net present value (NPV, return of investment (ROI, internal rate of return (IRR and payback period (PP. Sensitivity analysis of the NPV to the default discount rate (10% was included. A 8,000 ha plantation over 25 years was estimated to result in a positive NPV of USD 10,670 with a ROI 73.50% and an IRR at 14.83% and payback period of 6.75 years. Establishing an oil palm plantation seems to be very profitable investment on the basis of the assumptions made. System is tested on sensitivity in different capital and recurrent costs and in selling price of raw material, while change in selling price of FFB is more sensitive to NPV than change in investment and recurrent costs Discount rate is also one of the factors affecting NPV and system is tested between 5–15% change in discount rate.

Uncertainty and Sensitivity Analysis of Afterbody Radiative Heating Predictions for Earth Entry

Science.gov (United States)

West, Thomas K., IV; Johnston, Christopher O.; Hosder, Serhat

2016-01-01

The objective of this work was to perform sensitivity analysis and uncertainty quantification for afterbody radiative heating predictions of Stardust capsule during Earth entry at peak afterbody radiation conditions. The radiation environment in the afterbody region poses significant challenges for accurate uncertainty quantification and sensitivity analysis due to the complexity of the flow physics, computational cost, and large number of un-certain variables. In this study, first a sparse collocation non-intrusive polynomial chaos approach along with global non-linear sensitivity analysis was used to identify the most significant uncertain variables and reduce the dimensions of the stochastic problem. Then, a total order stochastic expansion was constructed over only the important parameters for an efficient and accurate estimate of the uncertainty in radiation. Based on previous work, 388 uncertain parameters were considered in the radiation model, which came from the thermodynamics, flow field chemistry, and radiation modeling. The sensitivity analysis showed that only four of these variables contributed significantly to afterbody radiation uncertainty, accounting for almost 95% of the uncertainty. These included the electronic- impact excitation rate for N between level 2 and level 5 and rates of three chemical reactions in uencing N, N(+), O, and O(+) number densities in the flow field.

Global optimization and sensitivity analysis

International Nuclear Information System (INIS)

Cacuci, D.G.

1990-01-01

A new direction for the analysis of nonlinear models of nuclear systems is suggested to overcome fundamental limitations of sensitivity analysis and optimization methods currently prevalent in nuclear engineering usage. This direction is toward a global analysis of the behavior of the respective system as its design parameters are allowed to vary over their respective design ranges. Presented is a methodology for global analysis that unifies and extends the current scopes of sensitivity analysis and optimization by identifying all the critical points (maxima, minima) and solution bifurcation points together with corresponding sensitivities at any design point of interest. The potential applicability of this methodology is illustrated with test problems involving multiple critical points and bifurcations and comprising both equality and inequality constraints

Cost-utility analysis of varenicline, an oral smoking-cessation drug, in Japan.

Science.gov (United States)

Igarashi, Ataru; Takuma, Hiroki; Fukuda, Takashi; Tsutani, Kiichiro

2009-01-01

To conduct a cost-utility analysis of two 12-week smoking-cessation interventions in Japan: smoking-cessation counselling by a physician compared with use of varenicline, an oral smoking-cessation drug, in addition to counselling. A Markov model was constructed to analyse lifetime medical costs and QALYs from the perspective of the healthcare payer. The cycle length was 5 years. Both costs and QALYs were discounted at 3% annually. The cohort of smokers was classified by sex and age, and we assumed that smokers started smoking at the age of 20 years and received smoking-cessation therapy at the ages of 30, 40, 50, 60 or 70 years (five separate models were run). The healthcare costs and QALYs were calculated throughout the term until the age of 90 years. In the base-case analysis, success rates of varenicline plus counselling and counselling alone were assumed to be 37.9% and 25.5%, respectively, in male smokers, and 22.2% and 16.1%, respectively, in female smokers, based on a randomized controlled trial conducted in Japan. Both univariate and probabilistic sensitivity analyses were conducted. Prescribed varenicline was shown to be more effective and less costly than smoking-cessation counselling alone. Varenicline would save direct medical costs of Japanese Yen (yen)43 846 ($US381; $US1 = yen115; Oct 2007) and generate an increase of 0.094 QALYs in male smokers. In females the incremental cost-effectiveness ratio was yen346 143 per QALY gained. Varenicline is estimated to save yen23.7 billion ($US206 million) of the medical costs for tobacco-associated diseases for the whole population. Overall savings are yen9.5 billion. Sensitivity analyses suggested the robustness of the results. As with any data of this nature, there is some uncertainty in the results and further research is warranted. However, based on the results of this pharmacoeconomic evaluation, varenicline, the first non-nicotine, oral treatment developed for smoking cessation, appears to be cost

Cost benefit analysis vs. referenda

OpenAIRE

Martin J. Osborne; Matthew A. Turner

2007-01-01

We consider a planner who chooses between two possible public policies and ask whether a referendum or a cost benefit analysis leads to higher welfare. We find that a referendum leads to higher welfare than a cost benefit analyses in "common value" environments. Cost benefit analysis is better in "private value" environments.

Fertility preservation for social indications: a cost-based decision analysis.

Science.gov (United States)

Hirshfeld-Cytron, Jennifer; Grobman, William A; Milad, Magdy P

2012-03-01

Age-related infertility remains a problem that assisted reproductive techniques (ART) have limited ability to overcome. Correspondingly, because an increasing number of women are choosing to delay childbearing, fertility preservation strategies, initially intended for patients undergoing gonadotoxic therapies, are being applied to this group of healthy women. Studies supporting the effectiveness of this practice are lacking. Decision analytic techniques. We compared the cost-effectiveness of three strategies for women planning delayed childbearing until age 40: oocyte cryopreservation at age 25, ovarian tissue cryopreservation (OTC) at age 25, and no assisted reproduction until spontaneous conception had been attempted. Not applicable. Not applicable. Cost-effectiveness, which was defined as the cost per live birth. In this analysis, the strategy of foregoing fertility preservation at age 25 and then choosing ART only after not spontaneously conceiving at age 40 was the most cost-effective option. OTC was dominated by the other strategies. Sensitivity analyses demonstrated the robustness of the model; no analysis existed in which OTC was not dominated by oocyte cryopreservation. Increasing the cost of an IVF cycle beyond $22,000 was the only situation in which oocyte cryopreservation was the most preferred strategy. Neither oocyte cryopreservation nor OTC appear to be cost-effective under current circumstances for otherwise healthy women planning delayed childbearing. This analysis should give pause to the current practice of offering fertility preservation based only on the desire for delayed childbearing. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Cost-effectiveness Analysis for Technology Acquisition.

Science.gov (United States)

Chakravarty, A; Naware, S S

2008-01-01

In a developing country with limited resources, it is important to utilize the total cost visibility approach over the entire life-cycle of the technology and then analyse alternative options for acquiring technology. The present study analysed cost-effectiveness of an "In-house" magnetic resonance imaging (MRI) scan facility of a large service hospital against outsourcing possibilities. Cost per unit scan was calculated by operating costing method and break-even volume was calculated. Then life-cycle cost analysis was performed to enable total cost visibility of the MRI scan in both "In-house" and "outsourcing of facility" configuration. Finally, cost-effectiveness analysis was performed to identify the more acceptable decision option. Total cost for performing unit MRI scan was found to be Rs 3,875 for scans without contrast and Rs 4,129 with contrast. On life-cycle cost analysis, net present value (NPV) of the "In-house" configuration was found to be Rs-(4,09,06,265) while that of "outsourcing of facility" configuration was Rs-(5,70,23,315). Subsequently, cost-effectiveness analysis across eight Figures of Merit showed the "In-house" facility to be the more acceptable option for the system. Every decision for acquiring high-end technology must be subjected to life-cycle cost analysis.

[Analysis of costs and cost-effectiveness of preferred GESIDA/National AIDS Plan regimens for initial antiretroviral therapy in human immunodeficiency virus infected adult patients in 2013].

Science.gov (United States)

Blasco, Antonio Javier; Llibre, Josep M; Arribas, José Ramón; Boix, Vicente; Clotet, Bonaventura; Domingo, Pere; González-García, Juan; Knobel, Hernando; López, Juan Carlos; Lozano, Fernando; Miró, José M; Podzamczer, Daniel; Santamaría, Juan Miguel; Tuset, Montserrat; Zamora, Laura; Lázaro, Pablo; Gatell, Josep M

2013-11-01

The GESIDA and National AIDS Plan panel of experts have proposed "preferred regimens" of antiretroviral treatment (ART) as initial therapy in HIV infected patients for 2013. The objective of this study is to evaluate the costs and effectiveness of initiating treatment with these "preferred regimens". An economic assessment of costs and effectiveness (cost/effectiveness) was performed using decision tree analysis models. Effectiveness was defined as the probability of having viral load <50copies/mL at week48, in an intention-to-treat analysis. Cost of initiating treatment with an ART regime was defined as the costs of ART and its consequences (adverse effects, changes of ART regime and drug resistance analyses) during the first 48weeks. The perspective of the analysis is that of the National Health System was applied, only taking into account differential direct costs: ART (official prices), management of adverse effects, resistance studies, and determination of HLA B*5701. The setting is Spain and the costs are those of 2013. A sensitivity deterministic analysis was performed, constructing three scenarios for each regimen: baseline, most favourable, and most unfavourable cases. In the baseline case scenario, the cost of initiating treatment ranges from 6,747euros for TDF/FTC+NVP to 12,059euros for TDF/FTC+RAL. The effectiveness ranges between 0.66 for ABC/3TC+LPV/r and ABC/3TC+ATV/r, and 0.87 for TDF/FTC+RAL and ABC/3TC+RAL. Effectiveness, in terms of cost/effectiveness, varies between 8,396euros and 13,930euros per responder at 48weeks, for TDF/FTC/RPV and TDF/FTC+RAL, respectively. Taking ART at official prices, the most effective regimen was TDF/FTC/RPV, followed by the rest of non-nucleoside containing regimens. The sensitivity analysis confirms the robustness of these findings. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Costs and cost-efficacy analysis of the 2014 GESIDA/Spanish National AIDS Plan recommended guidelines for initial antiretroviral therapy in HIV-infected adults.

Science.gov (United States)

Blasco, Antonio Javier; Llibre, Josep M; Berenguer, Juan; González-García, Juan; Knobel, Hernando; Lozano, Fernando; Podzamczer, Daniel; Pulido, Federico; Rivero, Antonio; Tuset, Montserrat; Lázaro, Pablo; Gatell, Josep M

2015-03-01

GESIDA and the National AIDS Plan panel of experts suggest preferred (PR) and alternative (AR) regimens of antiretroviral treatment (ART) as initial therapy in HIV-infected patients for 2014. The objective of this study is to evaluate the costs and the efficiency of initiating treatment with these regimens. An economic assessment was made of costs and efficiency (cost/efficacy) based on decision tree analyses. Efficacy was defined as the probability of reporting a viral load <50 copies/mL at week 48, in an intention-to-treat analysis. Cost of initiating treatment with an ART regimen was defined as the costs of ART and its consequences (adverse effects, changes of ART regimen, and drug resistance studies) during the first 48 weeks. The payer perspective (National Health System) was applied by considering only differential direct costs: ART (official prices), management of adverse effects, studies of resistance, and HLA B*5701 testing. The setting is Spain and costs correspond to those of 2014. A sensitivity deterministic analysis was conducted, building three scenarios for each regimen: base case, most favourable and least favourable. In the base case scenario, the cost of initiating treatment ranges from 5133 Euros for ABC/3TC+EFV to 11,949 Euros for TDF/FTC+RAL. The efficacy varies between 0.66 for ABC/3TC+LPV/r and ABC/3TC+ATV/r, and 0.89 for TDF/FTC/EVG/COBI. Efficiency, in terms of cost/efficacy, ranges from 7546 to 13,802 Euros per responder at 48 weeks, for ABC/3TC+EFV and TDF/FTC+RAL respectively. Considering ART official prices, the most efficient regimen was ABC/3TC+EFV (AR), followed by the non-nucleoside containing PR (TDF/FTC/RPV and TDF/FTC/EFV). The sensitivity analysis confirms the robustness of these findings. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Time-Dependent Global Sensitivity Analysis for Long-Term Degeneracy Model Using Polynomial Chaos

Directory of Open Access Journals (Sweden)

Jianbin Guo

2014-07-01

Full Text Available Global sensitivity is used to quantify the influence of uncertain model inputs on the output variability of static models in general. However, very few approaches can be applied for the sensitivity analysis of long-term degeneracy models, as far as time-dependent reliability is concerned. The reason is that the static sensitivity may not reflect the completed sensitivity during the entire life circle. This paper presents time-dependent global sensitivity analysis for long-term degeneracy models based on polynomial chaos expansion (PCE. Sobol’ indices are employed as the time-dependent global sensitivity since they provide accurate information on the selected uncertain inputs. In order to compute Sobol’ indices more efficiently, this paper proposes a moving least squares (MLS method to obtain the time-dependent PCE coefficients with acceptable simulation effort. Then Sobol’ indices can be calculated analytically as a postprocessing of the time-dependent PCE coefficients with almost no additional cost. A test case is used to show how to conduct the proposed method, then this approach is applied to an engineering case, and the time-dependent global sensitivity is obtained for the long-term degeneracy mechanism model.

An automated sensitivity analysis procedure for the performance assessment of nuclear waste isolation systems

International Nuclear Information System (INIS)

Pin, F.G.; Worley, B.A.; Oblow, E.M.; Wright, R.Q.; Harper, W.V.

1986-01-01

To support an effort in making large-scale sensitivity analyses feasible, cost efficient and quantitatively complete, the authors have developed an automated procedure making use of computer calculus. The procedure, called GRESS (GRadient Enhanced Software System), is embodied in a precompiler that can process Fortran computer codes and add derivative-taking capabilities to the normal calculation scheme. In this paper, the automated GRESS procedure is described and applied to the code UCB-NE-10.2, which simulates the migration through a sorption medium of the radionuclide members of a decay chain. The sensitivity calculations for a sample problem are verified using comparison with analytical and perturbation analysis results. Conclusions are drawn relative to the applicability of GRESS for more general large-scale sensitivity studies, and the role of such techniques in an overall sensitivity and uncertainty analysis program is discussed

Cost-effectiveness analysis of cochlear dose reduction by proton beam therapy for medulloblastoma in childhood

International Nuclear Information System (INIS)

Hirano, Emi; Kawabuchi, Koichi; Fuji, Hiroshi; Onoe, Tsuyoshi; Kumar, Vinay; Shirato, Hiroki

2014-01-01

The aim of this study is to evaluate the cost-effectiveness of proton beam therapy with cochlear dose reduction compared with conventional X-ray radiotherapy for medulloblastoma in childhood. We developed a Markov model to describe health states of 6-year-old children with medulloblastoma after treatment with proton or X-ray radiotherapy. The risks of hearing loss were calculated on cochlear dose for each treatment. Three types of health-related quality of life (HRQOL) of EQ-5D, HUI3 and SF-6D were used for estimation of quality-adjusted life years (QALYs). The incremental cost-effectiveness ratio (ICER) for proton beam therapy compared with X-ray radiotherapy was calculated for each HRQOL. Sensitivity analyses were performed to model uncertainty in these parameters. The ICER for EQ-5D, HUI3 and SF-6D were $21 716/QALY, $11 773/QALY, and $20 150/QALY, respectively. One-way sensitivity analyses found that the results were sensitive to discount rate, the risk of hearing loss after proton therapy, and costs of proton irradiation. Cost-effectiveness acceptability curve analysis revealed a 99% probability of proton therapy being cost effective at a societal willingness-to-pay value. Proton beam therapy with cochlear dose reduction improves health outcomes at a cost that is within the acceptable cost-effectiveness range from the payer's standpoint. (author)

Chemical kinetic functional sensitivity analysis: Elementary sensitivities

International Nuclear Information System (INIS)

Demiralp, M.; Rabitz, H.

1981-01-01

Sensitivity analysis is considered for kinetics problems defined in the space--time domain. This extends an earlier temporal Green's function method to handle calculations of elementary functional sensitivities deltau/sub i//deltaα/sub j/ where u/sub i/ is the ith species concentration and α/sub j/ is the jth system parameter. The system parameters include rate constants, diffusion coefficients, initial conditions, boundary conditions, or any other well-defined variables in the kinetic equations. These parameters are generally considered to be functions of position and/or time. Derivation of the governing equations for the sensitivities and the Green's funciton are presented. The physical interpretation of the Green's function and sensitivities is given along with a discussion of the relation of this work to earlier research

Cost-utility analysis comparing radioactive iodine, anti-thyroid drugs and total thyroidectomy for primary treatment of Graves' disease.

Science.gov (United States)

Donovan, Peter J; McLeod, Donald S A; Little, Richard; Gordon, Louisa

2016-12-01

Little data is in existence about the most cost-effective primary treatment for Graves' disease. We performed a cost-utility analysis comparing radioactive iodine (RAI), anti-thyroid drugs (ATD) and total thyroidectomy (TT) as first-line therapy for Graves' disease in England and Australia. We used a Markov model to compare lifetime costs and benefits (quality-adjusted life-years (QALYs)). The model included efficacy, rates of relapse and major complications associated with each treatment, and alternative second-line therapies. Model parameters were obtained from published literature. One-way sensitivity analyses were conducted. Costs were presented in 2015£ or Australian Dollars (AUD). RAI was the least expensive therapy in both England (£5425; QALYs 34.73) and Australia (AUD5601; 30.97 QALYs). In base case results, in both countries, ATD was a cost-effective alternative to RAI (£16 866; 35.17 QALYs; incremental cost-effectiveness ratio (ICER) £26 279 per QALY gained England; AUD8924; 31.37 QALYs; ICER AUD9687 per QALY gained Australia), while RAI dominated TT (£7115; QALYs 33.93 England; AUD15 668; 30.25 QALYs Australia). In sensitivity analysis, base case results were stable to changes in most cost, transition probabilities and health-relative quality-of-life (HRQoL) weights; however, in England, the results were sensitive to changes in the HRQoL weights of hypothyroidism and euthyroidism on ATD. In this analysis, RAI is the least expensive choice for first-line treatment strategy for Graves' disease. In England and Australia, ATD is likely to be a cost-effective alternative, while TT is unlikely to be cost-effective. Further research into HRQoL in Graves' disease could improve the quality of future studies. © 2016 European Society of Endocrinology.

Probabilistic sensitivity analysis of biochemical reaction systems.

Science.gov (United States)

Zhang, Hong-Xuan; Dempsey, William P; Goutsias, John

2009-09-07

Sensitivity analysis is an indispensable tool for studying the robustness and fragility properties of biochemical reaction systems as well as for designing optimal approaches for selective perturbation and intervention. Deterministic sensitivity analysis techniques, using derivatives of the system response, have been extensively used in the literature. However, these techniques suffer from several drawbacks, which must be carefully considered before using them in problems of systems biology. We develop here a probabilistic approach to sensitivity analysis of biochemical reaction systems. The proposed technique employs a biophysically derived model for parameter fluctuations and, by using a recently suggested variance-based approach to sensitivity analysis [Saltelli et al., Chem. Rev. (Washington, D.C.) 105, 2811 (2005)], it leads to a powerful sensitivity analysis methodology for biochemical reaction systems. The approach presented in this paper addresses many problems associated with derivative-based sensitivity analysis techniques. Most importantly, it produces thermodynamically consistent sensitivity analysis results, can easily accommodate appreciable parameter variations, and allows for systematic investigation of high-order interaction effects. By employing a computational model of the mitogen-activated protein kinase signaling cascade, we demonstrate that our approach is well suited for sensitivity analysis of biochemical reaction systems and can produce a wealth of information about the sensitivity properties of such systems. The price to be paid, however, is a substantial increase in computational complexity over derivative-based techniques, which must be effectively addressed in order to make the proposed approach to sensitivity analysis more practical.

Cost-Effectiveness Analysis of Three Leprosy Case Detection Methods in Northern Nigeria

Science.gov (United States)

Ezenduka, Charles; Post, Erik; John, Steven; Suraj, Abdulkarim; Namadi, Abdulahi; Onwujekwe, Obinna

2012-01-01

Background Despite several leprosy control measures in Nigeria, child proportion and disability grade 2 cases remain high while new cases have not significantly reduced, suggesting continuous spread of the disease. Hence, there is the need to review detection methods to enhance identification of early cases for effective control and prevention of permanent disability. This study evaluated the cost-effectiveness of three leprosy case detection methods in Northern Nigeria to identify the most cost-effective approach for detection of leprosy. Methods A cross-sectional study was carried out to evaluate the additional benefits of using several case detection methods in addition to routine practice in two north-eastern states of Nigeria. Primary and secondary data were collected from routine practice records and the Nigerian Tuberculosis and Leprosy Control Programme of 2009. The methods evaluated were Rapid Village Survey (RVS), Household Contact Examination (HCE) and Traditional Healers incentive method (TH). Effectiveness was measured as number of new leprosy cases detected and cost-effectiveness was expressed as cost per case detected. Costs were measured from both providers' and patients' perspectives. Additional costs and effects of each method were estimated by comparing each method against routine practise and expressed as incremental cost-effectiveness ratio (ICER). All costs were converted to the U.S. dollar at the 2010 exchange rate. Univariate sensitivity analysis was used to evaluate uncertainties around the ICER. Results The ICER for HCE was $142 per additional case detected at all contact levels and it was the most cost-effective method. At ICER of $194 per additional case detected, THs method detected more cases at a lower cost than the RVS, which was not cost-effective at $313 per additional case detected. Sensitivity analysis showed that varying the proportion of shared costs and subsistent wage for valuing unpaid time did not significantly change the

Cost-effectiveness analysis of EGFR mutation testing in patients with non-small cell lung cancer (NSCLC) with gefitinib or carboplatin-paclitaxel.

Science.gov (United States)

Arrieta, Oscar; Anaya, Pablo; Morales-Oyarvide, Vicente; Ramírez-Tirado, Laura Alejandra; Polanco, Ana C

2016-09-01

Assess the cost-effectiveness of an EGFR-mutation testing strategy for advanced NSCLC in first-line therapy with either gefitinib or carboplatin-paclitaxel in Mexican institutions. Cost-effectiveness analysis using a discrete event simulation (DES) model to simulate two therapeutic strategies in patients with advanced NSCLC. Strategy one included patients tested for EGFR-mutation and therapy given accordingly. Strategy two included chemotherapy for all patients without testing. All results are presented in 2014 US dollars. The analysis was made with data from the Mexican frequency of EGFR-mutation. A univariate sensitivity analysis was conducted on EGFR prevalence. Progression-free survival (PFS) transition probabilities were estimated on data from the IPASS and simulated with a Weibull distribution, run with parallel trials to calculate a probabilistic sensitivity analysis. PFS of patients in the testing strategy was 6.76 months (95 % CI 6.10-7.44) vs 5.85 months (95 % CI 5.43-6.29) in the non-testing group. The one-way sensitivity analysis showed that PFS has a direct relationship with EGFR-mutation prevalence, while the ICER and testing cost have an inverse relationship with EGFR-mutation prevalence. The probabilistic sensitivity analysis showed that all iterations had incremental costs and incremental PFS for strategy 1 in comparison with strategy 2. There is a direct relationship between the ICER and the cost of EGFR testing, with an inverse relationship with the prevalence of EGFR-mutation. When prevalence is >10 % ICER remains constant. This study could impact Mexican and Latin American health policies regarding mutation detection testing and treatment for advanced NSCLC.

Cost-effectiveness analysis of thiazolidinediones in uncontrolled type 2 diabetic patients receiving sulfonylureas and metformin in Thailand.

Science.gov (United States)

Chirakup, Suphachai; Chaiyakunapruk, Nathorn; Chaikledkeaw, Usa; Pongcharoensuk, Petcharat; Ongphiphadhanakul, Boonsong; Roze, Stephane; Valentine, William J; Palmer, Andrew J

2008-03-01

The national essential drug committee in Thailand suggested that only one of thiazolidinediones be included in hospital formulary but little was know about their cost-effectiveness values. This study aims to determine an incremental cost-effectiveness ratio of pioglitazone 45 mg compared with rosiglitazone 8 mg in uncontrolled type 2 diabetic patients receiving sulfonylureas and metformin in Thailand. A Markov diabetes model (Center for Outcome Research model) was used in this study. Baseline characteristics of patients were based on Thai diabetes registry project. Costs of diabetes were calculated mainly from Buddhachinaraj hospital. Nonspecific mortality rate and transition probabilities of death from renal replacement therapy were obtained from Thai sources. Clinical effectiveness of thiazolidinediones was retrieved from a meta-analysis. All analyses were based on the government hospital policymaker perspective. Both cost and outcomes were discounted with the rate of 3%. Base-case analyses were analyzed as incremental cost per quality-adjusted life year (QALY) gained. A series of sensitive analyses were performed. In base-case analysis, the pioglitazone group had a better clinical outcomes and higher lifetime costs. The incremental cost per QALY gained was 186,246 baht (US$ 5389). The acceptability curves showed that the probability of pioglitazone being cost-effective was 29% at the willingness to pay of one time of Thai gross domestic product per capita (GDP per capita). The effect of pioglitazone on %HbA1c decrease was the most sensitive to the final outcomes. Our findings showed that in type 2 diabetic patients who cannot control their blood glucose under the combination of sulfonylurea and metformin, the use of pioglitazone 45 mg fell in the cost-effective range recommended by World Health Organization (one to three times of GDP per capita) on average, compared to rosiglitazone 8 mg. Nevertheless, based on sensitivity analysis, its probability of being cost

Maternal sensitivity: a concept analysis.

Science.gov (United States)

Shin, Hyunjeong; Park, Young-Joo; Ryu, Hosihn; Seomun, Gyeong-Ae

2008-11-01

The aim of this paper is to report a concept analysis of maternal sensitivity. Maternal sensitivity is a broad concept encompassing a variety of interrelated affective and behavioural caregiving attributes. It is used interchangeably with the terms maternal responsiveness or maternal competency, with no consistency of use. There is a need to clarify the concept of maternal sensitivity for research and practice. A search was performed on the CINAHL and Ovid MEDLINE databases using 'maternal sensitivity', 'maternal responsiveness' and 'sensitive mothering' as key words. The searches yielded 54 records for the years 1981-2007. Rodgers' method of evolutionary concept analysis was used to analyse the material. Four critical attributes of maternal sensitivity were identified: (a) dynamic process involving maternal abilities; (b) reciprocal give-and-take with the infant; (c) contingency on the infant's behaviour and (d) quality of maternal behaviours. Maternal identity and infant's needs and cues are antecedents for these attributes. The consequences are infant's comfort, mother-infant attachment and infant development. In addition, three positive affecting factors (social support, maternal-foetal attachment and high self-esteem) and three negative affecting factors (maternal depression, maternal stress and maternal anxiety) were identified. A clear understanding of the concept of maternal sensitivity could be useful for developing ways to enhance maternal sensitivity and to maximize the developmental potential of infants. Knowledge of the attributes of maternal sensitivity identified in this concept analysis may be helpful for constructing measuring items or dimensions.

Cost Effectiveness Analysis of Quasi-Static Wireless Power Transfer for Plug-In Hybrid Electric Transit Buses: Preprint

Energy Technology Data Exchange (ETDEWEB)

Wang, Lijuan; Gonder, Jeff; Burton, Evan; Brooker, Aaron; Meintz, Andrew; Konan, Arnaud

2015-11-11

This study evaluates the costs and benefits associated with the use of a plug-in hybrid electric bus and determines the cost effectiveness relative to a conventional bus and a hybrid electric bus. A sensitivity sweep analysis was performed over a number of a different battery sizes, charging powers, and charging stations. The net present value was calculated for each vehicle design and provided the basis for the design evaluation. In all cases, given present day economic assumptions, the conventional bus achieved the lowest net present value while the optimal plug-in hybrid electric bus scenario reached lower lifetime costs than the hybrid electric bus. The study also performed parameter sensitivity analysis under low market potential assumptions and high market potential assumptions. The net present value of plug-in hybrid electric bus is close to that of conventional bus.

A Cost-Effectiveness Analysis of Reverse Total Shoulder Arthroplasty versus Hemiarthroplasty for the Management of Complex Proximal Humeral Fractures in the Elderly.

Science.gov (United States)

Osterhoff, Georg; O'Hara, Nathan N; D'Cruz, Jennifer; Sprague, Sheila A; Bansback, Nick; Evaniew, Nathan; Slobogean, Gerard P

2017-03-01

There is ongoing debate regarding the optimal surgical treatment of complex proximal humeral fractures in elderly patients. To evaluate the cost-effectiveness of reverse total shoulder arthroplasty (RTSA) compared with hemiarthroplasty (HA) in the management of complex proximal humeral fractures, using a cost-utility analysis. On the basis of data from published literature, a cost-utility analysis was conducted using decision tree and Markov modeling. A single-payer perspective, with a willingness-to-pay (WTP) threshold of Can$50,000 (Canadian dollars), and a lifetime time horizon were used. The incremental cost-effectiveness ratio (ICER) was used as the study's primary outcome measure. In comparison with HA, the incremental cost per quality-adjusted life-year gained for RTSA was Can$13,679. One-way sensitivity analysis revealed the model to be sensitive to the RTSA implant cost and the RTSA procedural cost. The ICER of Can$13,679 is well below the WTP threshold of Can$50,000, and probabilistic sensitivity analysis demonstrated that 92.6% of model simulations favored RTSA. Our economic analysis found that RTSA for the treatment of complex proximal humeral fractures in the elderly is the preferred economic strategy when compared with HA. The ICER of RTSA is well below standard WTP thresholds, and its estimate of cost-effectiveness is similar to other highly successful orthopedic strategies such as total hip arthroplasty for the treatment of hip arthritis. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Clinical Evaluation and Cost-Effectiveness Analysis of Serum Tumor Markers in Lung Cancer

Directory of Open Access Journals (Sweden)

Rong Wang

2013-01-01

Full Text Available The detection of serum tumor markers is valuable for the early diagnosis of lung cancer. Tumor markers are frequently used for the management of cancer patients. However, single markers are less efficient but marker combinations increase the cost, which is troublesome for clinics. To find an optimal serum marker combination panel that benefits the patients and the medical management system as well, four routine lung cancer serum markers (SCCA, NSE, CEA, and CYFRA21-1 were evaluated individually and in combination. Meanwhile, the costs and effects of these markers in clinical practice in China were assessed by cost-effectiveness analysis. As expected, combinations of these tumor markers improved their sensitivity for lung cancer and different combination panels had their own usefulness. NSE + CEA + CYFRA21-1 was the optimal combination panel with highest Youden’s index (0.64, higher sensitivity (75.76%, and specificity (88.57%, which can aid the clinical diagnosis of lung cancer. Nevertheless, the most cost-effective combination was SCCA + CEA, which can be used to screen the high-risk group.

Use of Tumor Markers in Gastrointestinal Cancers: Surgeon Perceptions and Cost-Benefit Trade-Off Analysis.

Science.gov (United States)

Acharya, Amish; Markar, Sheraz R; Matar, Michael; Ni, Melody; Hanna, George B

2017-05-01

Gastrointestinal cancers constitute the third most common cancers worldwide. Tumor markers have long since been used in the postoperative surveillance of these malignancies; however, the true value in clinical practice remains undetermined. This study aimed to evaluate the clinical utility of three tumor markers in colorectal and esophagogastric cancer. A systematic review of the literature was undertaken to elicit the sensitivity, specificity, statistical heterogeneity and ability to predict recurrence and metastases for carcinoembryonic antigen (CEA), cancer antigen (CA) 19-9 and CA125. European surgeons were surveyed to assess their current practice and the characteristics of tumor markers they most valued. Data from the included studies and survey were combined in a cost-benefit trade-off analysis to assess which tumor markers are of most use in clinical practice. Diagnostic sensitivity and specificity were ranked the most desirable characteristics of a tumor marker by those surveyed. Overall, 156 studies were included to inform the cost-benefit trade-off. The cost-benefit trade-off showed that CEA outperformed both CA19-9 and CA125, with lower financial cost and a higher sensitivity, and diagnostic accuracy for metastases at presentation (area under the curve [AUC] 0.70 vs. 0.61 vs. 0.46), as well as similar diagnostic accuracy for recurrence (AUC 0.46 vs. 0.48). Cost-benefit trade-off analysis identified CEA to be the best performing tumor marker. Further studies should seek to evaluate new tumor markers, with investigation tailored to factors that meet the requirements of practicing clinicians.

Cost Utility Analysis of Topical Steroids Compared With Dietary Elimination for Treatment of Eosinophilic Esophagitis.

Science.gov (United States)

Cotton, Cary C; Erim, Daniel; Eluri, Swathi; Palmer, Sarah H; Green, Daniel J; Wolf, W Asher; Runge, Thomas M; Wheeler, Stephanie; Shaheen, Nicholas J; Dellon, Evan S

2017-06-01

Topical corticosteroids or dietary elimination are recommended as first-line therapies for eosinophilic esophagitis, but data to directly compare these therapies are scant. We performed a cost utility comparison of topical corticosteroids and the 6-food elimination diet (SFED) in treatment of eosinophilic esophagitis, from the payer perspective. We used a modified Markov model based on current clinical guidelines, in which transition between states depended on histologic response simulated at the individual cohort-member level. Simulation parameters were defined by systematic review and meta-analysis to determine the base-case estimates and bounds of uncertainty for sensitivity analysis. Meta-regression models included adjustment for differences in study and cohort characteristics. In the base-case scenario, topical fluticasone was about as effective as SFED but more expensive at a 5-year time horizon ($9261.58 vs $5719.72 per person). SFED was more effective and less expensive than topical fluticasone and topical budesonide in the base-case scenario. Probabilistic sensitivity analysis revealed little uncertainty in relative treatment effectiveness. There was somewhat greater uncertainty in the relative cost of treatments; most simulations found SFED to be less expensive. In a cost utility analysis comparing topical corticosteroids and SFED for first-line treatment of eosinophilic esophagitis, the therapies were similar in effectiveness. SFED was on average less expensive, and more cost effective in most simulations, than topical budesonide and topical fluticasone, from a payer perspective and not accounting for patient-level costs or quality of life. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

A cost-effectiveness threshold analysis of a multidisciplinary structured educational intervention in pediatric asthma.

Science.gov (United States)

Rodriguez-Martinez, Carlos E; Sossa-Briceño, Monica P; Castro-Rodriguez, Jose A

2018-05-01

Asthma educational interventions have been shown to improve several clinically and economically important outcomes. However, these interventions are costly in themselves and could lead to even higher disease costs. A cost-effectiveness threshold analysis would be helpful in determining the threshold value of the cost of educational interventions, leading to these interventions being cost-effective. The aim of the present study was to perform a cost-effectiveness threshold analysis to determine the level at which the cost of a pediatric asthma educational intervention would be cost-effective and cost-saving. A Markov-type model was developed in order to estimate costs and health outcomes of a simulated cohort of pediatric patients with persistent asthma treated over a 12-month period. Effectiveness parameters were obtained from a single uncontrolled before-and-after study performed with Colombian asthmatic children. Cost data were obtained from official databases provided by the Colombian Ministry of Health. The main outcome was the variable "quality-adjusted life-years" (QALYs). A deterministic threshold sensitivity analysis showed that the asthma educational intervention will be cost-saving to the health system if its cost is under US$513.20. Additionally, the analysis showed that the cost of the intervention would have to be below US$967.40 in order to be cost-effective. This study identified the level at which the cost of a pediatric asthma educational intervention will be cost-effective and cost-saving for the health system in Colombia. Our findings could be a useful aid for decision makers in efficiently allocating limited resources when planning asthma educational interventions for pediatric patients.

[Cost-effectiveness analysis of delayed-release dimethyl-fumarate in the treatment of relapsing-remitting multiple sclerosis in Italy

Directory of Open Access Journals (Sweden)

Gianluca Furneri

2016-06-01

RESULTS: In the base-case analysis, DMF was more efficacious than alternatives, in terms of both survival (19.496 vs. 19.297-19.461 discounted LYs, respectively, and QALYs (6.548 vs. 5.172- 6.212 discounted QALYs, respectively. Per-patient lifetime costs with DMF amounted to € 276,500, similarly to the other options. DMF was the drug with the largest effect of disability cost reduction. DMF was dominant vs. IFN beta-1a 44 mcg and cost-effective vs. all other IFNs, GA and teriflunomide, with incremental cost-effectiveness ratio (ICERs between € 11,272 and € 23,409. All ICER values were lower than the € 50,000 per QALY threshold. One-way sensitivity analysis showed that, for all tested scenarios, ICER of DMF vs. therapeutic alternatives remained favourable (≤ 50.000 €/QALY gained and the results of probabilistic sensitivity analysis showed that the probability for DMF of being favourable (≤ 50.000 €/QALY gained was between around 70% and 93%, thus ensuring robustness of the results. CONCLUSIONS: The results of this economic analysis show that, at the current price and the described assumptions, DMF represents a cost-effective option vs. other available first-line treatments indicated in RRMS in the perspective of the Italian NHS. [Article in Italian

Cost-effectiveness analysis of treatment strategies for initial Clostridium difficile infection.

Science.gov (United States)

Varier, R U; Biltaji, E; Smith, K J; Roberts, M S; Jensen, M K; LaFleur, J; Nelson, R E

2014-12-01

Clostridium difficile infection (CDI) is costly. Current guidelines recommend metronidazole as first-line therapy and vancomycin as an alternative. Recurrence is common. Faecal microbiota transplantation (FMT) is an effective therapy for recurrent CDI (RCDI). This study explores the cost-effectiveness of FMT, vancomycin and metronidazole for initial CDI. We constructed a decision-analytic computer simulation using inputs from published literature to compare FMT with a 10-14-day course of oral metronidazole or vancomycin for initial CDI. Parameters included cure rates (baseline value (range)) for metronidazole (80% (65-85%)), vancomycin (90% (88-92%)) and FMT(91% (83-100%)). Direct costs of metronidazole, vancomycin and FMT, adjusted to 2011 dollars, were $57 ($43-72), $1347 ($1195-1499) and $1086 ($815-1358), respectively. Our effectiveness measure was quality-adjusted life years (QALYs). One-way and probabilistic sensitivity analyses were conducted from the third-party payer perspective. Analysis using baseline values showed that FMT($1669, 0.242 QALYs) dominated (i.e. was less costly and more effective) vancomycin ($1890, 0.241 QALYs). FMT was more costly and more effective than metronidazole ($1167, 0.238 QALYs), yielding an incremental cost-effectiveness ratio (ICER) of $124 964/QALY. One-way sensitivity analyses showed that metronidazole dominated both strategies if its probability of cure were >90%; FMT dominated if it cost costly. FMT and vancomycin are more effective. However, FMT is less likely to be economically favourable, and vancomycin is unlikely to be favourable as first-line therapy when compared with FMT. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

Cost-effectiveness analysis of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis.

Science.gov (United States)

Cardona-Arias, Jaiberth Antonio; López-Carvajal, Liliana; Tamayo Plata, Mery Patricia; Vélez, Iván Darío

2017-05-01

The treatment of cutaneous leishmaniasis is toxic, has contraindications, and a high cost. The objective of this study was to estimate the cost-effectiveness of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis. Effectiveness was the proportion of healing and safety with the adverse effects; these parameters were estimated from a controlled clinical trial and a meta-analysis. A standard costing was conducted. Average and incremental cost-effectiveness ratios were estimated. The uncertainty regarding effectiveness, safety, and costs was determined through sensitivity analyses. The total costs were $66,807 with Glucantime and $14,079 with thermotherapy. The therapeutic effectiveness rates were 64.2% for thermotherapy and 85.1% for Glucantime. The average cost-effectiveness ratios ranged between $721 and $1275 for Glucantime and between $187 and $390 for thermotherapy. Based on the meta-analysis, thermotherapy may be a dominant strategy. The excellent cost-effectiveness ratio of thermotherapy shows the relevance of its inclusion in guidelines for the treatment. © 2017 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd.

Micro-cost Analysis of ALK Rearrangement Testing by FISH to Determine Eligibility for Crizotinib Therapy in NSCLC: Implications for Cost Effectiveness of Testing and Treatment

Science.gov (United States)

Parker, David; Belaud-Rotureau, Marc-Antoine

2014-01-01

Break-apart fluorescence in situ hybridization (FISH) is the gold standard test for anaplastic lymphoma kinase (ALK) gene rearrangement. However, this methodology often is assumed to be expensive and potentially cost-prohibitive given the low prevalence of ALK-positive non-small cell lung cancer (NSCLC) cases. To more accurately estimate the cost of ALK testing by FISH, we developed a micro-cost model that accounts for all cost elements of the assay, including laboratory reagents, supplies, capital equipment, technical and pathologist labor, and the acquisition cost of the commercial test and associated reagent kits and controls. By applying a set of real-world base-case parameter values, we determined that the cost of a single ALK break-apart FISH test result is $278.01. Sensitivity analysis on the parameters of batch size, testing efficiency, and the cost of the commercial diagnostic testing products revealed that the cost per result is highly sensitive to batch size, but much less so to efficiency or product cost. This implies that ALK testing by FISH will be most cost effective when performed in high-volume centers. Our results indicate that testing cost may not be the primary determinant of crizotinib (Xalkori®) treatment cost effectiveness, and suggest that testing cost is an insufficient reason to limit the use of FISH testing for ALK rearrangement. PMID:25520569

Micro-cost Analysis of ALK Rearrangement Testing by FISH to Determine Eligibility for Crizotinib Therapy in NSCLC: Implications for Cost Effectiveness of Testing and Treatment.

Science.gov (United States)

Parker, David; Belaud-Rotureau, Marc-Antoine

2014-01-01

Break-apart fluorescence in situ hybridization (FISH) is the gold standard test for anaplastic lymphoma kinase (ALK) gene rearrangement. However, this methodology often is assumed to be expensive and potentially cost-prohibitive given the low prevalence of ALK-positive non-small cell lung cancer (NSCLC) cases. To more accurately estimate the cost of ALK testing by FISH, we developed a micro-cost model that accounts for all cost elements of the assay, including laboratory reagents, supplies, capital equipment, technical and pathologist labor, and the acquisition cost of the commercial test and associated reagent kits and controls. By applying a set of real-world base-case parameter values, we determined that the cost of a single ALK break-apart FISH test result is $278.01. Sensitivity analysis on the parameters of batch size, testing efficiency, and the cost of the commercial diagnostic testing products revealed that the cost per result is highly sensitive to batch size, but much less so to efficiency or product cost. This implies that ALK testing by FISH will be most cost effective when performed in high-volume centers. Our results indicate that testing cost may not be the primary determinant of crizotinib (Xalkori(®)) treatment cost effectiveness, and suggest that testing cost is an insufficient reason to limit the use of FISH testing for ALK rearrangement.

Advanced Fuel Cycle Economic Sensitivity Analysis

Energy Technology Data Exchange (ETDEWEB)

David Shropshire; Kent Williams; J.D. Smith; Brent Boore

2006-12-01

A fuel cycle economic analysis was performed on four fuel cycles to provide a baseline for initial cost comparison using the Gen IV Economic Modeling Work Group G4 ECON spreadsheet model, Decision Programming Language software, the 2006 Advanced Fuel Cycle Cost Basis report, industry cost data, international papers, the nuclear power related cost study from MIT, Harvard, and the University of Chicago. The analysis developed and compared the fuel cycle cost component of the total cost of energy for a wide range of fuel cycles including: once through, thermal with fast recycle, continuous fast recycle, and thermal recycle.

A Nuclear Waste Management Cost Model for Policy Analysis

Science.gov (United States)

Barron, R. W.; Hill, M. C.

2017-12-01

Although integrated assessments of climate change policy have frequently identified nuclear energy as a promising alternative to fossil fuels, these studies have often treated nuclear waste disposal very simply. Simple assumptions about nuclear waste are problematic because they may not be adequate to capture relevant costs and uncertainties, which could result in suboptimal policy choices. Modeling nuclear waste management costs is a cross-disciplinary, multi-scale problem that involves economic, geologic and environmental processes that operate at vastly different temporal scales. Similarly, the climate-related costs and benefits of nuclear energy are dependent on environmental sensitivity to CO2 emissions and radiation, nuclear energy's ability to offset carbon emissions, and the risk of nuclear accidents, factors which are all deeply uncertain. Alternative value systems further complicate the problem by suggesting different approaches to valuing intergenerational impacts. Effective policy assessment of nuclear energy requires an integrated approach to modeling nuclear waste management that (1) bridges disciplinary and temporal gaps, (2) supports an iterative, adaptive process that responds to evolving understandings of uncertainties, and (3) supports a broad range of value systems. This work develops the Nuclear Waste Management Cost Model (NWMCM). NWMCM provides a flexible framework for evaluating the cost of nuclear waste management across a range of technology pathways and value systems. We illustrate how NWMCM can support policy analysis by estimating how different nuclear waste disposal scenarios developed using the NWMCM framework affect the results of a recent integrated assessment study of alternative energy futures and their effects on the cost of achieving carbon abatement targets. Results suggest that the optimism reflected in previous works is fragile: Plausible nuclear waste management costs and discount rates appropriate for intergenerational cost

Cost-effectiveness of competing strategies for management of recurrent Clostridium difficile infection: a decision analysis.

Science.gov (United States)

Konijeti, Gauree G; Sauk, Jenny; Shrime, Mark G; Gupta, Meera; Ananthakrishnan, Ashwin N

2014-06-01

Clostridium difficile infection (CDI) is an important cause of morbidity and healthcare costs, and is characterized by high rates of disease recurrence. The cost-effectiveness of newer treatments for recurrent CDI has not been examined, yet would be important to inform clinical practice. The aim of this study was to analyze the cost effectiveness of competing strategies for recurrent CDI. We constructed a decision-analytic model comparing 4 treatment strategies for first-line treatment of recurrent CDI in a population with a median age of 65 years: metronidazole, vancomycin, fidaxomicin, and fecal microbiota transplant (FMT). We modeled up to 2 additional recurrences following the initial recurrence. We assumed FMT delivery via colonoscopy as our base case, but conducted sensitivity analyses based on different modes of delivery. Willingness-to-pay threshold was set at $50 000 per quality-adjusted life-year. At our base case estimates, initial treatment of recurrent CDI using FMT colonoscopy was the most cost-effective strategy, with an incremental cost-effectiveness ratio of $17 016 relative to oral vancomycin. Fidaxomicin and metronidazole were both dominated by FMT colonoscopy. On sensitivity analysis, FMT colonoscopy remained the most cost-effective strategy at cure rates >88.4% and CDI recurrence rates cost cost-effectiveness threshold. In clinical settings where FMT is not available or applicable, the preferred strategy appears to be initial treatment with oral vancomycin. In this decision analysis examining treatment strategies for recurrent CDI, we demonstrate that FMT colonoscopy is the most cost-effective initial strategy for management of recurrent CDI.

Cost-effectiveness Analysis in R Using a Multi-state Modeling Survival Analysis Framework: A Tutorial.

Science.gov (United States)

Williams, Claire; Lewsey, James D; Briggs, Andrew H; Mackay, Daniel F

2017-05-01

This tutorial provides a step-by-step guide to performing cost-effectiveness analysis using a multi-state modeling approach. Alongside the tutorial, we provide easy-to-use functions in the statistics package R. We argue that this multi-state modeling approach using a package such as R has advantages over approaches where models are built in a spreadsheet package. In particular, using a syntax-based approach means there is a written record of what was done and the calculations are transparent. Reproducing the analysis is straightforward as the syntax just needs to be run again. The approach can be thought of as an alternative way to build a Markov decision-analytic model, which also has the option to use a state-arrival extended approach. In the state-arrival extended multi-state model, a covariate that represents patients' history is included, allowing the Markov property to be tested. We illustrate the building of multi-state survival models, making predictions from the models and assessing fits. We then proceed to perform a cost-effectiveness analysis, including deterministic and probabilistic sensitivity analyses. Finally, we show how to create 2 common methods of visualizing the results-namely, cost-effectiveness planes and cost-effectiveness acceptability curves. The analysis is implemented entirely within R. It is based on adaptions to functions in the existing R package mstate to accommodate parametric multi-state modeling that facilitates extrapolation of survival curves.

Palbociclib in hormone receptor positive advanced breast cancer: A cost-utility analysis.

Science.gov (United States)

Raphael, J; Helou, J; Pritchard, K I; Naimark, D M

2017-11-01

The addition of palbociclib to letrozole improves progression-free survival in the first-line treatment of hormone receptor positive advanced breast cancer (ABC). This study assesses the cost-utility of palbociclib from the Canadian healthcare payer perspective. A probabilistic discrete event simulation (DES) model was developed and parameterised with data from the PALOMA 1 and 2 trials and other sources. The incremental cost per quality-adjusted life-month (QALM) gained for palbociclib was calculated. A time horizon of 15 years was used in the base case with costs and effectiveness discounted at 5% annually. Time-to- progression and time-to-death were derived from a Weibull and exponential distribution. Expected costs were based on Ontario fees and other sources. Probabilistic sensitivity analyses were conducted to account for parameter uncertainty. Compared to letrozole, the addition of palbociclib provided an additional 14.7 QALM at an incremental cost of $161,508. The resulting incremental cost-effectiveness ratio was $10,999/QALM gained. Assuming a willingness-to-pay (WTP) of $4167/QALM, the probability of palbociclib to be cost-effective was 0%. Cost-effectiveness acceptability curves derived from a probabilistic sensitivity analysis showed that at a WTP of $11,000/QALM gained, the probability of palbociclib to be cost-effective was 50%. The addition of palbociclib to letrozole is unlikely to be cost-effective for the treatment of ABC from a Canadian healthcare perspective with its current price. While ABC patients derive a meaningful clinical benefit from palbociclib, considerations should be given to increase the WTP threshold and reduce the drug pricing, to render this strategy more affordable. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cost Analysis of Noninvasive Helmet Ventilation Compared with Use of Noninvasive Face Mask in ARDS

Directory of Open Access Journals (Sweden)

Kwadwo Kyeremanteng

2018-01-01

Full Text Available Intensive care unit (ICU costs have doubled since 2000, totalling 108 billion dollars per year. Acute respiratory distress syndrome (ARDS has a prevalence of 10.4% and a 28-day mortality of 34.8%. Noninvasive ventilation (NIV is used in up to 30% of cases. A recent randomized controlled trial by Patel et al. (2016 showed lower intubation rates and 90-day mortality when comparing helmet to face mask NIV in ARDS. The population in the Patel et al. trial was used for cost analysis in this study. Projections of cost savings showed a decrease in ICU costs by $2527 and hospital costs by $3103 per patient, along with a 43.3% absolute reduction in intubation rates. Sensitivity analysis showed consistent cost reductions. Projected annual cost savings, assuming the current prevalence of ARDS, were $237538 in ICU costs and $291682 in hospital costs. At a national level, using yearly incidence of ARDS cases in American ICUs, this represents $449 million in savings. Helmet NIV, compared to face mask NIV, in nonintubated patients with ARDS, reduces ICU and hospital direct-variable costs along with intubation rates, LOS, and mortality. A large-scale cost-effectiveness analysis is needed to validate the findings.

Allocating provider resources to diagnose and treat restless legs syndrome: a cost-utility analysis.

Science.gov (United States)

Padula, William V; Phelps, Charles E; Moran, Dane; Earley, Christopher

2017-10-01

Restless legs syndrome (RLS) is a neurological disorder that is frequently misdiagnosed, resulting in delays in proper treatment. The objective of this study was to analyze the cost-utility of training primary care providers (PCP) in early and accurate diagnosis of RLS. We used a Markov model to compare two strategies: one where PCPs received training to diagnose RLS (informed care) and one where PCPs did not receive training (standard care). This analysis was conducted from the US societal and health sector perspectives over one-year, five-year, and lifetime (50-year) horizons. Costs were adjusted to 2016 USD, utilities measured as quality-adjusted life-years (QALYs), and both measures were discounted annually at 3%. Cost, utilities, and probabilities for the model were obtained through a comprehensive review of literature. An incremental cost-effectiveness ratio (ICER) was calculated to interpret our findings at a willingness-to-pay threshold of $100,000/QALY. Univariate and multivariate analyses were conducted to test model uncertainty, in addition to calculating the expected value of perfect information. Providing training to PCPs to correctly diagnose RLS was cost-effective since it cost $2021 more and gained 0.44 QALYs per patient over the course of a lifetime, resulting in an ICER of $4593/QALY. The model was sensitive to the utility for treated and untreated RLS. The probabilistic sensitivity analysis revealed that at $100,000/QALY, informed care had a 65.5% probability of being cost-effective. A program to train PCPs to better diagnose RLS appears to be a cost-effective strategy for improving outcomes for RLS patients. Copyright © 2017 Elsevier B.V. All rights reserved.

ADGEN: a system for automated sensitivity analysis of predictive models

International Nuclear Information System (INIS)

Pin, F.G.; Horwedel, J.E.; Oblow, E.M.; Lucius, J.L.

1986-09-01

A system that can automatically enhance computer codes with a sensitivity calculation capability is presented. With this new system, named ADGEN, rapid and cost-effective calculation of sensitivities can be performed in any FORTRAN code for all input data or parameters. The resulting sensitivities can be used in performance assessment studies related to licensing or interactions with the public to systematically and quantitatively prove the relative importance of each of the system parameters in calculating the final performance results. A general procedure calling for the systematic use of sensitivities in assessment studies is presented. The procedure can be used in modelling and model validation studies to avoid ''over modelling,'' in site characterization planning to avoid ''over collection of data,'' and in performance assessment to determine the uncertainties on the final calculated results. The added capability to formally perform the inverse problem, i.e., to determine the input data or parameters on which to focus additional research or analysis effort in order to improve the uncertainty of the final results, is also discussed

Cost-Risk Trade-off of Solar Radiation Management and Mitigation under Probabilistic Information on Climate Sensitivity

Science.gov (United States)

Khabbazan, Mohammad Mohammadi; Roshan, Elnaz; Held, Hermann

2017-04-01

In principle solar radiation management (SRM) offers an option to ameliorate anthropogenic temperature rise. However we cannot expect it to simultaneously compensate for anthropogenic changes in further climate variables in a perfect manner. Here, we ask to what extent a proponent of the 2°C-temperature target would apply SRM in conjunction with mitigation in view of global or regional disparities in precipitation changes. We apply cost-risk analysis (CRA), which is a decision analytic framework that makes a trade-off between the expected welfare-loss from climate policy costs and the climate risks from transgressing a climate target. Here, in both global-scale and 'Giorgi'-regional-scale analyses, we evaluate the optimal mixture of SRM and mitigation under probabilistic information about climate sensitivity. To do so, we generalize CRA for the sake of including not only temperature risk, but also globally aggregated and regionally disaggregated precipitation risks. Social welfare is maximized for the following three valuation scenarios: temperature-risk-only, precipitation-risk-only, and equally weighted both-risks. For now, the Giorgi regions are treated by equal weight. We find that for regionally differentiated precipitation targets, the usage of SRM will be comparably more restricted. In the course of time, a cooling of up to 1.3°C can be attributed to SRM for the latter scenario and for a median climate sensitivity of 3°C (for a global target only, this number reduces by 0.5°C). Our results indicate that although SRM would almost completely substitute for mitigation in the globally aggregated analysis, it only saves 70% to 75% of the welfare-loss compared to a purely mitigation-based analysis (from economic costs and climate risks, approximately 4% in terms of BGE) when considering regional precipitation risks in precipitation-risk-only and both-risks scenarios. It remains to be shown how the inclusion of further risks or different regional weights would

Clinical benefits, costs, and cost-effectiveness of neonatal intensive care in Mexico.

Directory of Open Access Journals (Sweden)

Jochen Profit

2010-12-01

Full Text Available Neonatal intensive care improves survival, but is associated with high costs and disability amongst survivors. Recent health reform in Mexico launched a new subsidized insurance program, necessitating informed choices on the different interventions that might be covered by the program, including neonatal intensive care. The purpose of this study was to estimate the clinical outcomes, costs, and cost-effectiveness of neonatal intensive care in Mexico.A cost-effectiveness analysis was conducted using a decision analytic model of health and economic outcomes following preterm birth. Model parameters governing health outcomes were estimated from Mexican vital registration and hospital discharge databases, supplemented with meta-analyses and systematic reviews from the published literature. Costs were estimated on the basis of data provided by the Ministry of Health in Mexico and World Health Organization price lists, supplemented with published studies from other countries as needed. The model estimated changes in clinical outcomes, life expectancy, disability-free life expectancy, lifetime costs, disability-adjusted life years (DALYs, and incremental cost-effectiveness ratios (ICERs for neonatal intensive care compared to no intensive care. Uncertainty around the results was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. In the base-case analysis, neonatal intensive care for infants born at 24-26, 27-29, and 30-33 weeks gestational age prolonged life expectancy by 28, 43, and 34 years and averted 9, 15, and 12 DALYs, at incremental costs per infant of US$11,400, US$9,500, and US$3,000, respectively, compared to an alternative of no intensive care. The ICERs of neonatal intensive care at 24-26, 27-29, and 30-33 weeks were US$1,200, US$650, and US$240, per DALY averted, respectively. The findings were robust to variation in parameter values over wide ranges in sensitivity analyses

Partial-Breast Irradiation Versus Whole-Breast Irradiation for Early-Stage Breast Cancer: A Cost-Effectiveness Analysis

International Nuclear Information System (INIS)

Sher, David J.; Wittenberg, Eve; Suh, W. Warren; Taghian, Alphonse G.; Punglia, Rinaa S.

2009-01-01

Purpose: Accelerated partial-breast irradiation (PBI) is a new treatment paradigm for patients with early-stage breast cancer. Although PBI may lead to greater local recurrence rates, it may be cost-effective because of better tolerability and lower cost. We aim to determine the incremental cost-effectiveness of PBI compared with whole-breast radiation therapy (WBRT) for estrogen receptor-positive postmenopausal women treated for early-stage breast cancer. Methods and Materials: We developed a Markov model to describe health states in the 15 years after radiotherapy for early-stage breast cancer. External beam (EB) and MammoSite (MS) PBI were considered and assumed to be equally effective, but carried different costs. Patients received tamoxifen, but not chemotherapy. Utilities, recurrence risks, and costs were adapted from the literature; the baseline utility for no disease after radiotherapy was set at 0.92. Probabilistic sensitivity analyses were performed to model uncertainty in the PBI hazard ratio, recurrence pattern, and patient utilities. Costs (in 2004 US dollars) and quality-adjusted life-years were discounted at 3%/y. Results: The incremental cost-effectiveness ratio for WBRT compared with EB-PBI was $630,000/quality-adjusted life-year; WBRT strongly dominated MS-PBI. One-way sensitivity analysis found that results were sensitive to PBI hazard ratio, recurrence pattern, baseline recurrence risk, and no evidence of disease PBI utility values. Probabilistic sensitivity showed that EB-PBI was the most cost-effective technique over a wide range of assumptions and societal willingness-to-pay values. Conclusions: EB-PBI was the most cost-effective strategy for postmenopausal women with early-stage breast cancer. Unless the quality of life after MS-PBI proves to be superior, it is unlikely to be cost-effective.

Cost-effectiveness of FDG-PET for the management of solitary pulmonary nodules: a decision analysis based on cost reimbursement in Germany

International Nuclear Information System (INIS)

Dietlein, M.; Weber, K.; Moka, D.; Theissen, P.; Schicha, H.; Gandjour, A.; Lauterbach, K.W.

2000-01-01

Management of solitary pulmonary nodules (SPNs) of up to 3 cm was modelled on decision analysis comparing ''wait and watch'', transthoracic needle biopsy (TNB), exploratory surgery and full-ring dedicated positron emission tomography (PET) using fluorine-18 2-fluorodeoxyglucose (FDG). The incremental cost-effectiveness ratios (ICERs) were calculated for the main risk group, a cohort of 62-year-old men, using first ''wait and watch'' and second exploratory surgery as the baseline strategy. Based on published data, the sensitivity and specificity of FDG-PET were estimated at 0.95 and 0.80 for detecting malignancy in SPNs and at 0.74 and 0.96 for detecting metastasis in normal-sized mediastinal lymph nodes. The costs quoted correspond to reimbursement in 1999 by the public health provider in Germany. Decision analysis modelling indicates the potential cost-effectiveness of the FDG-PET strategy for management of SPNs. Taking watchful waiting as the low-cost baseline strategy, the ICER of PET [3218 euros (EUR) per life year saved] was more favourable than that of exploratory surgery (4210 EUR/year) or that of TNB (6120 EUR/year). Changing the baseline strategy to exploratory surgery, the use of PET led to cost savings and additional life expectancy. This constellation was described by a negative ICER of -6912 EUR/year. The PET algorithm was cost-effective for risk and non-risk patients. However, the ICER of PET as the preferred strategy was sensitive to a hypothetical deterioration of any PET parameters by more than 0.07. To transfer the diagnostic efficacy from controlled studies to the routine user and to maintain the cost-effectiveness of this technology, obligatory protocols for data acquisitions would need to be defined. If the prevalence of SPNs is estimated at the USA level (52 per 100,000 individuals) and assuming that multiple strategies without PET are the norm, the overall costs of a newly implemented PET algorithm would be limited to far less than one EUR

Cost-Effectiveness Analysis of Probiotic Use to Prevent Clostridium difficile Infection in Hospitalized Adults Receiving Antibiotics.

Science.gov (United States)

Shen, Nicole T; Leff, Jared A; Schneider, Yecheskel; Crawford, Carl V; Maw, Anna; Bosworth, Brian; Simon, Matthew S

2017-01-01

Systematic reviews with meta-analyses and meta-regression suggest that timely probiotic use can prevent Clostridium difficile infection (CDI) in hospitalized adults receiving antibiotics, but the cost effectiveness is unknown. We sought to evaluate the cost effectiveness of probiotic use for prevention of CDI versus no probiotic use in the United States. We programmed a decision analytic model using published literature and national databases with a 1-year time horizon. The base case was modeled as a hypothetical cohort of hospitalized adults (mean age 68) receiving antibiotics with and without concurrent probiotic administration. Projected outcomes included quality-adjusted life-years (QALYs), costs (2013 US dollars), incremental cost-effectiveness ratios (ICERs; $/QALY), and cost per infection avoided. One-way, two-way, and probabilistic sensitivity analyses were conducted, and scenarios of different age cohorts were considered. The ICERs less than $100000 per QALY were considered cost effective. Probiotic use dominated (more effective and less costly) no probiotic use. Results were sensitive to probiotic efficacy (relative risk 1.6%), the risk of probiotic-associated bactermia/fungemia (cost (65). In probabilistic sensitivity analysis, at a willingness-to-pay threshold of $100000/QALY, probiotics were the optimal strategy in 69.4% of simulations. Our findings suggest that probiotic use may be a cost-effective strategy to prevent CDI in hospitalized adults receiving antibiotics age 65 or older or when the baseline risk of CDI exceeds 1.6%.

Cost-Effectiveness Analysis of Probiotic Use to Prevent Clostridium difficile Infection in Hospitalized Adults Receiving Antibiotics

Science.gov (United States)

Leff, Jared A; Schneider, Yecheskel; Crawford, Carl V; Maw, Anna; Bosworth, Brian; Simon, Matthew S

2017-01-01

Abstract Background Systematic reviews with meta-analyses and meta-regression suggest that timely probiotic use can prevent Clostridium difficile infection (CDI) in hospitalized adults receiving antibiotics, but the cost effectiveness is unknown. We sought to evaluate the cost effectiveness of probiotic use for prevention of CDI versus no probiotic use in the United States. Methods We programmed a decision analytic model using published literature and national databases with a 1-year time horizon. The base case was modeled as a hypothetical cohort of hospitalized adults (mean age 68) receiving antibiotics with and without concurrent probiotic administration. Projected outcomes included quality-adjusted life-years (QALYs), costs (2013 US dollars), incremental cost-effectiveness ratios (ICERs; $/QALY), and cost per infection avoided. One-way, two-way, and probabilistic sensitivity analyses were conducted, and scenarios of different age cohorts were considered. The ICERs less than $100000 per QALY were considered cost effective. Results Probiotic use dominated (more effective and less costly) no probiotic use. Results were sensitive to probiotic efficacy (relative risk CDI (>1.6%), the risk of probiotic-associated bactermia/fungemia (cost (65). In probabilistic sensitivity analysis, at a willingness-to-pay threshold of $100000/QALY, probiotics were the optimal strategy in 69.4% of simulations. Conclusions Our findings suggest that probiotic use may be a cost-effective strategy to prevent CDI in hospitalized adults receiving antibiotics age 65 or older or when the baseline risk of CDI exceeds 1.6%. PMID:29230429

The source of investment cash flow sensitivity in manufacturing firms: Is it asymmetric information or agency costs?

Directory of Open Access Journals (Sweden)

Daniel Makina

2016-09-01

Full Text Available In the literature, positive investment cash flow sensitivity is attributed to either asymmetric information induced financing constraints or the agency costs of free cash flow. Using data from a sample of 68 manufacturing firms listed on the South African JSE, this paper contributes to the literature by investigating the source of investment cash flow sensitivity. We have found that asymmetric information explains the positive investment cash flow sensitivity better than agency costs. Furthermore, asymmetric information has been observed to be more pronounced in low-dividend-paying firms and small firms. Despite South Africa’s having a developed financial system by international standards, small firms are seen to be financially constrained. We attribute the absence of investment cash flow sensitivity due to agency costs to good corporate governance of South African listed firms. Thus the paper provides further evidence in support of the proposition in the literature that the source of investment cash flow sensitivity may depend on the institutional setting of a country, such as its corporate governance.

Cost-benefit analysis of avian influenza control in Nepal.

Science.gov (United States)

Karki, S; Lupiani, B; Budke, C M; Karki, N P S; Rushton, J; Ivanek, R

2015-12-01

Numerous outbreaks of highly pathogenic avian influenza A strain H5N1 have occurred in Nepal since 2009 despite implementation of a national programme to control the disease through surveillance and culling of infected poultry flocks. The objective of the study was to use cost-benefit analysis to compare the current control programme (CCP) with the possible alternatives of: i) no intervention (i.e., absence of control measures [ACM]) and ii) vaccinating 60% of the national poultry flock twice a year. In terms of the benefit-cost ratio, findings indicate a return of US $1.94 for every dollar spent in the CCP compared with ACM. The net present value of the CCP versus ACM, i.e., the amount of money saved by implementing the CCP rather than ACM, is US $861,507 (the benefits of CCP [prevented losses which would have occurred under ACM] minus the cost of CCP). The vaccination programme yields a return of US $2.32 for every dollar spent when compared with the CCR The net present value of vaccination versus the CCP is approximately US $12 million. Sensitivity analysis indicated thatthe findings were robust to different rates of discounting, whereas results were sensitive to the assumed market loss and the number of birds affected in the outbreaks under the ACM and vaccination options. Overall, the findings of the study indicate that the CCP is economically superior to ACM, but that vaccination could give greater economic returns and may be a better control strategy. Future research should be directed towards evaluating the financial feasibility and social acceptability of the CCP and of vaccination, with an emphasis on evaluating market reaction to the presence of H5N1 infection in the country.

Costs and cost-effectiveness of pediatric inguinal hernia repair in Uganda.

Science.gov (United States)

Eeson, Gareth; Birabwa-Male, Doreen; Pennington, Mark; Blair, Geoffrey K

2015-02-01

Surgically treatable diseases contribute approximately 11% of disability-adjusted life years (DALYs) worldwide yet they remain a neglected public health priority in low- and middle-income countries (LMICs). Pediatric inguinal hernia is the most common congenital abnormality in newborns and a major cause of morbidity and mortality yet elective repair remains largely unavailable in LMICs. This study is aimed to determine the costs and cost-effectiveness of pediatric inguinal hernia repair (PIHR) in a low-resource setting. Medical costs of consecutive elective PIHRs were recorded prospectively at two centers in Uganda. Decision modeling was used to compare two different treatment scenarios (adoption of PIHR and non-adoption) from a provider perspective. A Markov model was constructed to estimate health outcomes under each scenario. The robustness of the cost-effectiveness results in the base case analysis was tested in one-way and probabilistic sensitivity analysis. The primary outcome of interest was cost per DALY averted by the intervention. Sixty-nine PIHRs were performed in 65 children (mean age 3.6 years). Mean cost per procedure was $86.68 US (95% CI 83.1-90.2 USD) and averted an average of 5.7 DALYs each. Incremental cost-effectiveness ratio was $12.41 per DALY averted. The probability of cost-effectiveness was 95% at a cost-effectiveness threshold of $35 per averted DALY. Results were robust to sensitivity analysis under all considered scenarios. Elective PIHR is highly cost-effective for the treatment and prevention of complications of hernia disease even in low-resource settings. PIHR should be prioritized in LMICs alongside other cost-effective interventions.

Addition of docetaxel and/or zoledronic acid to standard of care for hormone-naive prostate cancer: a cost-effectiveness analysis.

Science.gov (United States)

Zhang, Pengfei; Wen, Feng; Fu, Ping; Yang, Yu; Li, Qiu

2017-07-31

The effectiveness of the addition of docetaxel and/or zoledronic acid to the standard of care (SOC) for hormone-naive prostate cancer has been evaluated in the STAMPEDE trial. The object of the present analysis was to evaluate the cost-effectiveness of these treatment options in the treatment of advanced hormone-naive prostate cancer in China. A cost-effectiveness analysis using a Markov model was carried out from the Chinese societal perspective. The efficacy data were obtained from the STAMPEDE trial and health utilities were derived from previous studies. Transition probabilities were calculated based on the survival in each group. The primary endpoint in the analysis was the incremental cost-effectiveness ratio (ICER), and model uncertainties were explored by 1-way sensitivity analysis and probabilistic sensitivity analysis. SOC alone generated an effectiveness of 2.65 quality-adjusted life years (QALYs) at a lifetime cost of $20,969.23. At a cost of $25,001.34, SOC plus zoledronic acid was associated with 2.69 QALYs, resulting in an ICER of $100,802.75/QALY compared with SOC alone. SOC plus docetaxel gained an effectiveness of 2.85 QALYs at a cost of $28,764.66, while the effectiveness and cost data in the SOC plus zoledronic acid/docetaxel group were 2.78 QALYs and $32,640.95. Based on the results of the analysis, SOC plus zoledronic acid, SOC plus docetaxel, and SOC plus zoledronic acid/docetaxel are unlikely to be cost-effective options in patients with advanced hormone-naive prostate cancer compared with SOC alone.

Cost analysis of a school-based comprehensive malaria program in primary schools in Sikasso region, Mali.

Science.gov (United States)

Maccario, Roberta; Rouhani, Saba; Drake, Tom; Nagy, Annie; Bamadio, Modibo; Diarra, Seybou; Djanken, Souleymane; Roschnik, Natalie; Clarke, Siân E; Sacko, Moussa; Brooker, Simon; Thuilliez, Josselin

2017-06-12

The expansion of malaria prevention and control to school-aged children is receiving increasing attention, but there are still limited data on the costs of intervention. This paper analyses the costs of a comprehensive school-based intervention strategy, delivered by teachers, that included participatory malaria educational activities, distribution of long lasting insecticide-treated nets (LLIN), and Intermittent Parasite Clearance in schools (IPCs) in southern Mali. Costs were collected alongside a randomised controlled trial conducted in 80 primary schools in Sikasso Region in Mali in 2010-2012. Cost data were compiled between November 2011 and March 2012 for the 40 intervention schools (6413 children). A provider perspective was adopted. Using an ingredients approach, costs were classified by cost category and by activity. Total costs and cost per child were estimated for the actual intervention, as well as for a simpler version of the programme more suited for scale-up by the government. Univariate sensitivity analysis was performed. The economic cost of the comprehensive intervention was estimated to $10.38 per child (financial cost $8.41) with malaria education, LLIN distribution and IPCs costing $2.13 (20.5%), $5.53 (53.3%) and $2.72 (26.2%) per child respectively. Human resources were found to be the key cost driver, and training costs were the greatest contributor to overall programme costs. Sensitivity analysis showed that an adapted intervention delivering one LLIN instead of two would lower the economic cost to $8.66 per child; and that excluding LLIN distribution in schools altogether, for example in settings where malaria control already includes universal distribution of LLINs at community-level, would reduce costs to $4.89 per child. A comprehensive school-based control strategy may be a feasible and affordable way to address the burden of malaria among schoolchildren in the Sahel.

Cost analysis of a school-based comprehensive malaria program in primary schools in Sikasso region, Mali

Directory of Open Access Journals (Sweden)

Roberta Maccario

2017-06-01

Full Text Available Abstract Background The expansion of malaria prevention and control to school-aged children is receiving increasing attention, but there are still limited data on the costs of intervention. This paper analyses the costs of a comprehensive school-based intervention strategy, delivered by teachers, that included participatory malaria educational activities, distribution of long lasting insecticide-treated nets (LLIN, and Intermittent Parasite Clearance in schools (IPCs in southern Mali. Methods Costs were collected alongside a randomised controlled trial conducted in 80 primary schools in Sikasso Region in Mali in 2010-2012. Cost data were compiled between November 2011 and March 2012 for the 40 intervention schools (6413 children. A provider perspective was adopted. Using an ingredients approach, costs were classified by cost category and by activity. Total costs and cost per child were estimated for the actual intervention, as well as for a simpler version of the programme more suited for scale-up by the government. Univariate sensitivity analysis was performed. Results The economic cost of the comprehensive intervention was estimated to $10.38 per child (financial cost $8.41 with malaria education, LLIN distribution and IPCs costing $2.13 (20.5%, $5.53 (53.3% and $2.72 (26.2% per child respectively. Human resources were found to be the key cost driver, and training costs were the greatest contributor to overall programme costs. Sensitivity analysis showed that an adapted intervention delivering one LLIN instead of two would lower the economic cost to $8.66 per child; and that excluding LLIN distribution in schools altogether, for example in settings where malaria control already includes universal distribution of LLINs at community-level, would reduce costs to $4.89 per child. Conclusions A comprehensive school-based control strategy may be a feasible and affordable way to address the burden of malaria among schoolchildren in the Sahel.

Sensitivity analysis of U238 cross section in thermal nuclear systems

International Nuclear Information System (INIS)

Amorim, E.S. do; D'Oliveira, A.B.; Oliveira, E.C. de; Moura Neto, C. de.

1980-01-01

A sensitivity analysis system is developed for assessing the implication of uncertainties in nuclear data and related computational methods for light water power reactor. Sensitivies, at equilibrium cycle condition, are carried out for the few group macroscopic cross section of the U 238 with respect to their 35 group microscopic absorption cross section using the batch depletion code SENTEAV similar to those calculation methods used in the industry. This investigation indicates that improvements are requested on specific range of energy. These results point out the direction for worth while experimental measurements based on an analysis of costs and economic benefits. (Author) [pt

Sensitivity Analysis of Corrosion Rate Prediction Models Utilized for Reinforced Concrete Affected by Chloride

Science.gov (United States)

Siamphukdee, Kanjana; Collins, Frank; Zou, Roger

2013-06-01

Chloride-induced reinforcement corrosion is one of the major causes of premature deterioration in reinforced concrete (RC) structures. Given the high maintenance and replacement costs, accurate modeling of RC deterioration is indispensable for ensuring the optimal allocation of limited economic resources. Since corrosion rate is one of the major factors influencing the rate of deterioration, many predictive models exist. However, because the existing models use very different sets of input parameters, the choice of model for RC deterioration is made difficult. Although the factors affecting corrosion rate are frequently reported in the literature, there is no published quantitative study on the sensitivity of predicted corrosion rate to the various input parameters. This paper presents the results of the sensitivity analysis of the input parameters for nine selected corrosion rate prediction models. Three different methods of analysis are used to determine and compare the sensitivity of corrosion rate to various input parameters: (i) univariate regression analysis, (ii) multivariate regression analysis, and (iii) sensitivity index. The results from the analysis have quantitatively verified that the corrosion rate of steel reinforcement bars in RC structures is highly sensitive to corrosion duration time, concrete resistivity, and concrete chloride content. These important findings establish that future empirical models for predicting corrosion rate of RC should carefully consider and incorporate these input parameters.

Design windows and cost analysis on helical reactors

International Nuclear Information System (INIS)

Kozaki, Y.; Imagawa, S.; Sagara, A.

2007-01-01

The LHD type helical reactors are characterized by a large major radius but slender helical coil, which give us different approaches for power plants from tokamak reactors. For searching design windows of helical reactors and discussing their potential as power plants, we have developed a mass-cost estimating model linked with system design code (HeliCos), thorough studying the relationships between major plasma parameters and reactor parameters, and weight of major components. In regard to cost data we have much experience through preparing ITER construction. To compare the weight and cost of magnet systems between tokamak and helical reactors, we broke down magnet systems and cost factors, such as weights of super conducting strands, conduits, support structures, and winding unit costs, through estimating ITER cost data basis. Based on FFHR2m1 deign we considered a typical 3 GWth helical plant (LHD type) with the same magnet size, coil major radius Rc 14 m, magnetic energy 120 GJ, but increasing plasma densities. We evaluated the weight and cost of magnet systems of 3 GWth helical plant, the total magnet weights of 16,000ton and costs of 210 BYen, which are similar values of tokamak reactors (10,200 ton, 110 BYen in ITER 2002 report, and 21,900 ton, 275 BYen in ITER FDR1999). The costs of strands and winding occupy 70% of total magnet costs, and influence entire power plants economics. The design windows analysis and comparative economics studies to optimize the main reactor parameters have been carried out. Economics studies show that it is misunderstanding to consider helical coils are too large and too expensive to achieve power plants. But we should notice that the helical reactor design windows and economics are very sensitive to allowable blanket space (depend on ergodic layer conditions) and diverter configuration for decreasing heat loads. (orig.)

Robotic and endoscopic transaxillary thyroidectomies may be cost prohibitive when compared to standard cervical thyroidectomy: a cost analysis.

Science.gov (United States)

Cabot, Jennifer C; Lee, Cho Rok; Brunaud, Laurent; Kleiman, David A; Chung, Woong Youn; Fahey, Thomas J; Zarnegar, Rasa

2012-12-01

This study presents a cost analysis of the standard cervical, gasless transaxillary endoscopic, and gasless transaxillary robotic thyroidectomy approaches based on medical costs in the United States. A retrospective review of 140 patients who underwent standard cervical, transaxillary endoscopic, or transaxillary robotic thyroidectomy at 2 tertiary centers was conducted. The cost model included operating room charges, anesthesia fee, consumables cost, equipment depreciation, and maintenance cost. Sensitivity analyses assessed individual cost variables. The mean operative times for the standard cervical, transaxillary endoscopic, and transaxillary robotic approaches were 121 ± 18.9, 185 ± 26.0, and 166 ± 29.4 minutes, respectively. The total cost for the standard cervical, transaxillary endoscopic, and transaxillary robotic approaches were $9,028 ± $891, $12,505 ± $1,222, and $13,670 ± $1,384, respectively. Transaxillary approaches were significantly more expensive than the standard cervical technique (standard cervical/transaxillary endoscopic, P cost when transaxillary endoscopic operative time decreased to 111 minutes and transaxillary robotic operative time decreased to 68 minutes. Increasing the case load did not resolve the cost difference. Transaxillary endoscopic and transaxillary robotic thyroidectomies are significantly more expensive than the standard cervical approach. Decreasing operative times reduces this cost difference. The greater expense may be prohibitive in countries with a flat reimbursement schedule. Copyright © 2012 Mosby, Inc. All rights reserved.

A highly sensitive, low-cost, wearable pressure sensor based on conductive hydrogel spheres

KAUST Repository

Tai, Yanlong; Mulle, Matthieu; Ventura, Isaac Aguilar; Lubineau, Gilles

2015-01-01

Wearable pressure sensing solutions have promising future for practical applications in health monitoring and human/machine interfaces. Here, a highly sensitive, low-cost, wearable pressure sensor based on conductive single-walled carbon nanotube

Cost and sensitivity of restricted active-space calculations of metal L-edge X-ray absorption spectra.

Science.gov (United States)

Pinjari, Rahul V; Delcey, Mickaël G; Guo, Meiyuan; Odelius, Michael; Lundberg, Marcus

2016-02-15

The restricted active-space (RAS) approach can accurately simulate metal L-edge X-ray absorption spectra of first-row transition metal complexes without the use of any fitting parameters. These characteristics provide a unique capability to identify unknown chemical species and to analyze their electronic structure. To find the best balance between cost and accuracy, the sensitivity of the simulated spectra with respect to the method variables has been tested for two models, [FeCl6 ](3-) and [Fe(CN)6 ](3-) . For these systems, the reference calculations give deviations, when compared with experiment, of ≤1 eV in peak positions, ≤30% for the relative intensity of major peaks, and ≤50% for minor peaks. When compared with these deviations, the simulated spectra are sensitive to the number of final states, the inclusion of dynamical correlation, and the ionization potential electron affinity shift, in addition to the selection of the active space. The spectra are less sensitive to the quality of the basis set and even a double-ζ basis gives reasonable results. The inclusion of dynamical correlation through second-order perturbation theory can be done efficiently using the state-specific formalism without correlating the core orbitals. Although these observations are not directly transferable to other systems, they can, together with a cost analysis, aid in the design of RAS models and help to extend the use of this powerful approach to a wider range of transition metal systems. © 2015 Wiley Periodicals, Inc.

Cost-effectiveness analysis of repeat fine-needle aspiration for thyroid biopsies read as atypia of undetermined significance.

Science.gov (United States)

Heller, Michael; Zanocco, Kyle; Zydowicz, Sara; Elaraj, Dina; Nayar, Ritu; Sturgeon, Cord

2012-09-01

The 2007 National Cancer Institute (NCI) conference on Thyroid Fine-Needle Aspiration (FNA) introduced the category atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS). Repeat FNA in 3 to 6 months was recommended for low-risk patients. Compliance with these recommendations has been suboptimal. We hypothesized that repeat FNA would be more effective than diagnostic lobectomy, with decreased costs and improved rates of cancer detection. Cost-effectiveness analysis was performed in which we compared diagnostic lobectomy with repeat FNA. A Markov model was developed. Outcomes and probabilities were identified from literature review. Third-party payer costs were estimated in 2010 US dollars. Outcomes were weighted by use of the quality-of-life utility factors, yielding quality-adjusted life years (QALYs). Monte Carlo simulation and sensitivity analysis were used to examine the uncertainty of probability, cost, and utility estimates. The diagnostic lobectomy strategy cost $8,057 and produced 23.99 QALYs. Repeat FNA cost $2,462 and produced 24.05 QALYs. Repeat FNA was dominant until the cost of FNA increased to $6,091. Dominance of the repeat FNA strategy was not sensitive to the cost of operation or the complication rate. The NCI recommendations for repeat FNA regarding follow-up of AUS/FLUS results are cost-effective. Improving compliance with these guidelines should lead to less overall costs, greater quality of life, and fewer unnecessary operations. Copyright © 2012 Mosby, Inc. All rights reserved.

Is testosterone replacement therapy in males with hypogonadism cost-effective? An analysis in Sweden.

Science.gov (United States)

Arver, Stefan; Luong, Ba; Fraschke, Anina; Ghatnekar, Ola; Stanisic, Sanja; Gultyev, Dmitry; Müller, Elvira

2014-01-01

Testosterone replacement therapy (TRT) has been recommended for the treatment of primary and secondary hypogonadism. However, long-term implications of TRT have not been investigated extensively. The aim of this analysis was to evaluate health outcomes and costs associated with life-long TRT in patients suffering from Klinefelter syndrome and late-onset hypogonadism (LOH). A Markov model was developed to assess cost-effectiveness of testosterone undecanoate (TU) depot injection treatment compared with no treatment. Health outcomes and associated costs were modeled in monthly cycles per patient individually along a lifetime horizon. Modeled health outcomes included development of type 2 diabetes, depression, cardiovascular and cerebrovascular complications, and fractures. Analysis was performed for the Swedish health-care setting from health-care payer's and societal perspective. One-way sensitivity analyses evaluated the robustness of results. The main outcome measures were quality-adjusted life-years (QALYs) and total cost in TU depot injection treatment and no treatment cohorts. In addition, outcomes were also expressed as incremental cost per QALY gained for TU depot injection therapy compared with no treatment (incremental cost-effectiveness ratio [ICER]). TU depot injection compared to no-treatment yielded a gain of 1.67 QALYs at an incremental cost of 28,176 EUR (37,192 USD) in the Klinefelter population. The ICER was 16,884 EUR (22,287 USD) per QALY gained. Outcomes in LOH population estimated benefits of TRT at 19,719 EUR (26,029 USD) per QALY gained. Results showed to be considerably robust when tested in sensitivity analyses. Variation of relative risk to develop type 2 diabetes had the highest impact on long-term outcomes in both patient groups. This analysis suggests that lifelong TU depot injection therapy of patients with hypogonadism is a cost-effective treatment in Sweden. Hence, it can support clinicians in decision making when considering

Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Anal Cancer

Energy Technology Data Exchange (ETDEWEB)

Hodges, Joseph C., E-mail: joseph.hodges@utsouthwestern.edu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Beg, Muhammad S. [Division of Hematology and Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Das, Prajnan [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Meyer, Jeffrey [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)

2014-07-15

Purpose: To compare the cost-effectiveness of intensity modulated radiation therapy (IMRT) and 3-dimensional conformal radiation therapy (3D-CRT) for anal cancer and determine disease, patient, and treatment parameters that influence the result. Methods and Materials: A Markov decision model was designed with the various disease states for the base case of a 65-year-old patient with anal cancer treated with either IMRT or 3D-CRT and concurrent chemotherapy. Health states accounting for rates of local failure, colostomy failure, treatment breaks, patient prognosis, acute and late toxicities, and the utility of toxicities were informed by existing literature and analyzed with deterministic and probabilistic sensitivity analysis. Results: In the base case, mean costs and quality-adjusted life expectancy in years (QALY) for IMRT and 3D-CRT were $32,291 (4.81) and $28,444 (4.78), respectively, resulting in an incremental cost-effectiveness ratio of $128,233/QALY for IMRT compared with 3D-CRT. Probabilistic sensitivity analysis found that IMRT was cost-effective in 22%, 47%, and 65% of iterations at willingness-to-pay thresholds of $50,000, $100,000, and $150,000 per QALY, respectively. Conclusions: In our base model, IMRT was a cost-ineffective strategy despite the reduced acute treatment toxicities and their associated costs of management. The model outcome was sensitive to variations in local and colostomy failure rates, as well as patient-reported utilities relating to acute toxicities.

Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Anal Cancer

International Nuclear Information System (INIS)

Hodges, Joseph C.; Beg, Muhammad S.; Das, Prajnan; Meyer, Jeffrey

2014-01-01

Purpose: To compare the cost-effectiveness of intensity modulated radiation therapy (IMRT) and 3-dimensional conformal radiation therapy (3D-CRT) for anal cancer and determine disease, patient, and treatment parameters that influence the result. Methods and Materials: A Markov decision model was designed with the various disease states for the base case of a 65-year-old patient with anal cancer treated with either IMRT or 3D-CRT and concurrent chemotherapy. Health states accounting for rates of local failure, colostomy failure, treatment breaks, patient prognosis, acute and late toxicities, and the utility of toxicities were informed by existing literature and analyzed with deterministic and probabilistic sensitivity analysis. Results: In the base case, mean costs and quality-adjusted life expectancy in years (QALY) for IMRT and 3D-CRT were $32,291 (4.81) and $28,444 (4.78), respectively, resulting in an incremental cost-effectiveness ratio of $128,233/QALY for IMRT compared with 3D-CRT. Probabilistic sensitivity analysis found that IMRT was cost-effective in 22%, 47%, and 65% of iterations at willingness-to-pay thresholds of $50,000, $100,000, and $150,000 per QALY, respectively. Conclusions: In our base model, IMRT was a cost-ineffective strategy despite the reduced acute treatment toxicities and their associated costs of management. The model outcome was sensitive to variations in local and colostomy failure rates, as well as patient-reported utilities relating to acute toxicities

Dedicated Perioperative Hip Fracture Comanagement Programs are Cost-effective in High-volume Centers: An Economic Analysis.

Science.gov (United States)

Swart, Eric; Vasudeva, Eshan; Makhni, Eric C; Macaulay, William; Bozic, Kevin J

2016-01-01

a full-time basis. Additionally, we evaluated the scenario where the necessary staff was already employed at the hospital and could be dedicated to a comanagement service on a part-time basis, and explored the effect of triaging only patients considered high risk to a comanagement service versus comanaging all geriatric patients. Finally, probabilistic sensitivity analysis was conducted on all critical variables, with broad ranges used for values around which there was higher uncertainty. For the base case, universal comanagement was more cost effective than traditional care and risk-stratified comanagement (incremental cost effectiveness ratios of USD 41,100 per quality-adjusted life-year and USD 81,900 per quality-adjusted life-year, respectively). Comanagement was more cost effective than traditional management as long as the case volume was more than 54 patients annually (range, 41-68 patients based on sensitivity analysis) and resulted in cost savings when there were more than 318 patients annually (range, 238-397 patients). In a scenario where staff could be partially dedicated to a comanagement service, universal comanagement was more cost effective than risk-stratified comanagement (incremental cost effectiveness of USD 2300 per quality-adjusted life-year), and both comanagement programs had lower costs and better outcomes compared with traditional management. Sensitivity analysis was conducted and showed that the level of uncertainty in key variables was not high enough to change the core conclusions of the model. Implementation of a systems-based comanagement strategy using a dedicated team to improve perioperative medical care and expedite preoperative evaluation is cost effective in hospitals with moderate volume and can result in cost savings at higher-volume centers. The optimum patient population for a comanagement strategy is still being defined. Level 1, Economic and Decision Analysis.

Modelling User-Costs in Life Cycle Cost-Benefit (LCCB) analysis

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

2008-01-01

The importance of including user's costs in Life-Cycle Cost-Benefit analysis of structures is discussed in this paper. This is especially for bridges of great importance. Repair or/and failure of a bridge will usually result in user costs greater than the repair or replacement costs of the bridge...

Incorporating psychological influences in probabilistic cost analysis

Energy Technology Data Exchange (ETDEWEB)

Kujawski, Edouard; Alvaro, Mariana; Edwards, William

2004-01-08

Today's typical probabilistic cost analysis assumes an ''ideal'' project that is devoid of the human and organizational considerations that heavily influence the success and cost of real-world projects. In the real world ''Money Allocated Is Money Spent'' (MAIMS principle); cost underruns are rarely available to protect against cost overruns while task overruns are passed on to the total project cost. Realistic cost estimates therefore require a modified probabilistic cost analysis that simultaneously models the cost management strategy including budget allocation. Psychological influences such as overconfidence in assessing uncertainties and dependencies among cost elements and risks are other important considerations that are generally not addressed. It should then be no surprise that actual project costs often exceed the initial estimates and are delivered late and/or with a reduced scope. This paper presents a practical probabilistic cost analysis model that incorporates recent findings in human behavior and judgment under uncertainty, dependencies among cost elements, the MAIMS principle, and project management practices. Uncertain cost elements are elicited from experts using the direct fractile assessment method and fitted with three-parameter Weibull distributions. The full correlation matrix is specified in terms of two parameters that characterize correlations among cost elements in the same and in different subsystems. The analysis is readily implemented using standard Monte Carlo simulation tools such as {at}Risk and Crystal Ball{reg_sign}. The analysis of a representative design and engineering project substantiates that today's typical probabilistic cost analysis is likely to severely underestimate project cost for probability of success values of importance to contractors and procuring activities. The proposed approach provides a framework for developing a viable cost management strategy for

Interference and Sensitivity Analysis.

Science.gov (United States)

VanderWeele, Tyler J; Tchetgen Tchetgen, Eric J; Halloran, M Elizabeth

2014-11-01

Causal inference with interference is a rapidly growing area. The literature has begun to relax the "no-interference" assumption that the treatment received by one individual does not affect the outcomes of other individuals. In this paper we briefly review the literature on causal inference in the presence of interference when treatments have been randomized. We then consider settings in which causal effects in the presence of interference are not identified, either because randomization alone does not suffice for identification, or because treatment is not randomized and there may be unmeasured confounders of the treatment-outcome relationship. We develop sensitivity analysis techniques for these settings. We describe several sensitivity analysis techniques for the infectiousness effect which, in a vaccine trial, captures the effect of the vaccine of one person on protecting a second person from infection even if the first is infected. We also develop two sensitivity analysis techniques for causal effects in the presence of unmeasured confounding which generalize analogous techniques when interference is absent. These two techniques for unmeasured confounding are compared and contrasted.

A sensitivity analysis of process design parameters, commodity prices and robustness on the economics of odour abatement technologies.

Science.gov (United States)

Estrada, José M; Kraakman, N J R Bart; Lebrero, Raquel; Muñoz, Raúl

2012-01-01

The sensitivity of the economics of the five most commonly applied odour abatement technologies (biofiltration, biotrickling filtration, activated carbon adsorption, chemical scrubbing and a hybrid technology consisting of a biotrickling filter coupled with carbon adsorption) towards design parameters and commodity prices was evaluated. Besides, the influence of the geographical location on the Net Present Value calculated for a 20 years lifespan (NPV20) of each technology and its robustness towards typical process fluctuations and operational upsets were also assessed. This comparative analysis showed that biological techniques present lower operating costs (up to 6 times) and lower sensitivity than their physical/chemical counterparts, with the packing material being the key parameter affecting their operating costs (40-50% of the total operating costs). The use of recycled or partially treated water (e.g. secondary effluent in wastewater treatment plants) offers an opportunity to significantly reduce costs in biological techniques. Physical/chemical technologies present a high sensitivity towards H2S concentration, which is an important drawback due to the fluctuating nature of malodorous emissions. The geographical analysis evidenced high NPV20 variations around the world for all the technologies evaluated, but despite the differences in wage and price levels, biofiltration and biotrickling filtration are always the most cost-efficient alternatives (NPV20). When, in an economical evaluation, the robustness is as relevant as the overall costs (NPV20), the hybrid technology would move up next to BTF as the most preferred technologies. Copyright © 2012 Elsevier Inc. All rights reserved.

Cost minimisation analysis of fingolimod vs natalizumab as a second line of treatment for relapsing-remitting multiple sclerosis.

Science.gov (United States)

Crespo, C; Izquierdo, G; García-Ruiz, A; Granell, M; Brosa, M

2014-05-01

At present, there is a lack of economic assessments of second-line treatments for relapsing-recurring multiple sclerosis. The aim of this study was to compare the efficiency between fingolimod and natalizumab in Spain. A cost minimisation analysis model was developed for a 2-year horizon. The same relapse rate was applied to both treatment arms and the cost of resources was calculated using Spain's stipulated rates for 2012 in euros. The analysis was conducted from the perspective of Spain's national health system and an annual discount rate of 3% was applied to future costs. A sensitivity analysis was performed to validate the robustness of the model. Indirect comparison of fingolimod with natalizumab revealed no significant differences (hazard ratio between 0.82 and 1.07). The total direct cost, considering a 2-year analytical horizon, a 7.5% discount stipulated by Royal Decree, and a mean annual relapse rate of 0.22, was € 40914.72 for fingolimod and € 45890.53 for natalizumab. Of the total direct costs that were analysed, the maximum cost savings derived from prescribing fingolimod prescription was € 4363.63, corresponding to lower administration and treatment maintenance costs. Based on the sensitivity analysis performed, fingolimod use was associated with average savings of 11% (range 3.1%-18.7%). Fingolimod is more efficient than natalizumab as a second-line treatment option for relapsing-remitting multiple sclerosis and it generates savings for the Spanish national health system. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Cost-effectiveness Analysis Appraisal and Application: An Emergency Medicine Perspective.

Science.gov (United States)

April, Michael D; Murray, Brian P

2017-06-01

Cost-effectiveness is an important goal for emergency care delivery. The many diagnostic, treatment, and disposition decisions made in the emergency department (ED) have a significant impact upon healthcare resource utilization. Cost-effectiveness analysis (CEA) is an analytic tool to optimize these resource allocation decisions through the systematic comparison of costs and effects of alternative healthcare decisions. Yet few emergency medicine leaders and policymakers have any formal training in CEA methodology. This paper provides an introduction to the interpretation and use of CEA with a focus on application to emergency medicine problems and settings. It applies a previously published CEA to the hypothetical case of a patient presenting to the ED with chest pain who requires risk stratification. This paper uses a widely cited checklist to appraise the CEA. This checklist serves as a vehicle for presenting basic CEA terminology and concepts. General topics of focus include measurement of costs and outcomes, incremental analysis, and sensitivity analysis. Integrated throughout the paper are recommendations for good CEA practice with emphasis on the guidelines published by the U.S. Panel on Cost-Effectiveness in Health and Medicine. Unique challenges for emergency medicine CEAs discussed include the projection of long-term outcomes from emergent interventions, costing ED services, and applying study results to diverse patient populations across various ED settings. The discussion also includes an overview of the limitations inherent in applying CEA results to clinical practice to include the lack of incorporation of noncost considerations in CEA (e.g., ethics). After reading this article, emergency medicine leaders and researchers will have an enhanced understanding of the basics of CEA critical appraisal and application. The paper concludes with an overview of economic evaluation resources for readers interested in conducting ED-based economic evaluation

Cost-effectiveness Analysis of Nutritional Support for the Prevention of Pressure Ulcers in High-Risk Hospitalized Patients.

Science.gov (United States)

Tuffaha, Haitham W; Roberts, Shelley; Chaboyer, Wendy; Gordon, Louisa G; Scuffham, Paul A

2016-06-01

To evaluate the cost-effectiveness of nutritional support compared with standard care in preventing pressure ulcers (PrUs) in high-risk hospitalized patients. An economic model using data from a systematic literature review. A meta-analysis of randomized controlled trials on the efficacy of nutritional support in reducing the incidence of PrUs was conducted. Modeled cohort of hospitalized patients at high risk of developing PrUs and malnutrition simulated during their hospital stay and up to 1 year. Standard care included PrU prevention strategies, such as redistribution surfaces, repositioning, and skin protection strategies, along with standard hospital diet. In addition to the standard care, the intervention group received nutritional support comprising patient education, nutrition goal setting, and the consumption of high-protein supplements. The analysis was from a healthcare payer perspective. Key outcomes of the model included the average costs and quality-adjusted life years. Model results were tested in univariate sensitivity analyses, and decision uncertainty was characterized using a probabilistic sensitivity analysis. Compared with standard care, nutritional support was cost saving at AU $425 per patient and marginally more effective with an average 0.005 quality-adjusted life years gained. The probability of nutritional support being cost-effective was 87%. Nutritional support to prevent PrUs in high-risk hospitalized patients is cost-effective with substantial cost savings predicted. Hospitals should implement the recommendations from the current PrU practice guidelines and offer nutritional support to high-risk patients.

Finite mixture models for sensitivity analysis of thermal hydraulic codes for passive safety systems analysis

Energy Technology Data Exchange (ETDEWEB)

Di Maio, Francesco, E-mail: francesco.dimaio@polimi.it [Energy Department, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Nicola, Giancarlo [Energy Department, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Zio, Enrico [Energy Department, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Chair on System Science and Energetic Challenge Fondation EDF, Ecole Centrale Paris and Supelec, Paris (France); Yu, Yu [School of Nuclear Science and Engineering, North China Electric Power University, 102206 Beijing (China)

2015-08-15

Highlights: • Uncertainties of TH codes affect the system failure probability quantification. • We present Finite Mixture Models (FMMs) for sensitivity analysis of TH codes. • FMMs approximate the pdf of the output of a TH code with a limited number of simulations. • The approach is tested on a Passive Containment Cooling System of an AP1000 reactor. • The novel approach overcomes the results of a standard variance decomposition method. - Abstract: For safety analysis of Nuclear Power Plants (NPPs), Best Estimate (BE) Thermal Hydraulic (TH) codes are used to predict system response in normal and accidental conditions. The assessment of the uncertainties of TH codes is a critical issue for system failure probability quantification. In this paper, we consider passive safety systems of advanced NPPs and present a novel approach of Sensitivity Analysis (SA). The approach is based on Finite Mixture Models (FMMs) to approximate the probability density function (i.e., the uncertainty) of the output of the passive safety system TH code with a limited number of simulations. We propose a novel Sensitivity Analysis (SA) method for keeping the computational cost low: an Expectation Maximization (EM) algorithm is used to calculate the saliency of the TH code input variables for identifying those that most affect the system functional failure. The novel approach is compared with a standard variance decomposition method on a case study considering a Passive Containment Cooling System (PCCS) of an Advanced Pressurized reactor AP1000.

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

Science.gov (United States)

Ruiz-Ramos, Jesus; Frasquet, Juan; Romá, Eva; Poveda-Andres, Jose Luis; Salavert-Leti, Miguel; Castellanos, Alvaro; Ramirez, Paula

2017-06-01

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

Cost-effectiveness analysis of PET-CT-guided management for locally advanced head and neck cancer.

Science.gov (United States)

Smith, A F; Hall, P S; Hulme, C T; Dunn, J A; McConkey, C C; Rahman, J K; McCabe, C; Mehanna, H

2017-11-01

A recent large United Kingdom (UK) clinical trial demonstrated that positron-emission tomography-computed tomography (PET-CT)-guided administration of neck dissection (ND) in patients with advanced head and neck cancer after primary chemo-radiotherapy treatment produces similar survival outcomes to planned ND (standard care) and is cost-effective over a short-term horizon. Further assessment of long-term outcomes is required to inform a robust adoption decision. Here we present results of a lifetime cost-effectiveness analysis of PET-CT-guided management from a UK secondary care perspective. Initial 6-month cost and health outcomes were derived from trial data; subsequent incidence of recurrence and mortality was simulated using a de novo Markov model. Health benefit was measured in quality-adjusted life years (QALYs) and costs reported in 2015 British pounds. Model parameters were derived from trial data and published literature. Sensitivity analyses were conducted to assess the impact of uncertainty and broader National Health Service (NHS) and personal social services (PSS) costs on the results. PET-CT management produced an average per-person lifetime cost saving of £1485 and an additional 0.13 QALYs. At a £20,000 willingness-to-pay per additional QALY threshold, there was a 75% probability that PET-CT was cost-effective, and the results remained cost-effective over the majority of sensitivity analyses. When adopting a broader NHS and PSS perspective, PET-CT management produced an average saving of £700 and had an 81% probability of being cost-effective. This analysis indicates that PET-CT-guided management is cost-effective in the long-term and supports the case for wide-scale adoption. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cost-benefit analysis of prophylactic granulocyte colony-stimulating factor during CHOP antineoplastic therapy for non-Hodgkin's lymphoma.

Science.gov (United States)

Dranitsaris, G; Altmayer, C; Quirt, I

1997-06-01

Several randomised comparative trials have shown that granulocyte colony-stimulating factor (G-CSF) reduces the duration of neutropenia, hospitalisation and intravenous antibacterial use in patients with cancer who are receiving high-dosage antineoplastic therapy. However, one area that has received less attention is the role of G-CSF in standard-dosage antineoplastic regimens. One such treatment that is considered to have a low potential for inducing fever and neutropenia is the CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisone) for non-Hodgkin's lymphoma. We conducted a cost-benefit analysis from a societal perspective in order to estimate the net cost or benefit of prophylactic G-CSF in this patient population. This included direct costs for hospitalisation with antibacterial support, as well as indirect societal costs, such as time off work and antineoplastic therapy delays secondary to neutropenia. The findings were then tested by a comprehensive sensitivity analysis. The administration of G-CSF at a dosage of 5 micrograms/kg/day for 11 doses following CHOP resulted in an overall net cost of $Can1257. In the sensitivity analysis, lowering the G-CSF dosage to 2 micrograms/kg/day generated a net benefit of $Can6564, indicating a situation that was cost saving to society. The results of the current study suggest that the use of G-CSF in patients receiving CHOP antineoplastic therapy produces a situation that is close to achieving cost neutrality. However, low-dosage (2 micrograms/kg/day) G-CSF is an economically attractive treatment strategy because it may result in overall savings to society.

Cost analysis of paroxetine versus imipramine in major depression.

Science.gov (United States)

Bentkover, J D; Feighner, J P

1995-09-01

A simulation decision analytical model was used to compare the annual direct medical costs of treating patients with major depression using the selective serotonin reuptake inhibitor (SSRI) paroxetine or the tricyclic antidepressant (TCA) imipramine. Medical treatment patterns were determined from focus groups of general and family practitioners and psychiatrists in Boston, Dallas and Chicago, US. Direct medical costs included the wholesale drug acquisition costs (based on a 6-month course of drug therapy), psychiatrist and/or general practitioner visits, hospital outpatient visits, hospitalisation and electroconvulsive therapy. Acute phase treatment failure rates were derived from an intention-to-treat analysis of a previously published trial of paroxetine, imipramine and placebo in patients with major depression. Maintenance phase relapse rates were obtained from a 12-month trial of paroxetine, supplemented from the medical literature. The relapse rates for the final 6 months of the year were obtained from medical literature and expert opinion. Direct medical costs were estimated from a health insurance claims database. The estimated total direct medical cost per patient was slightly lower using paroxetine ($US2348) than generic imipramine ($US2448) as first-line therapy. This result was sensitive to short term dropout rates but robust to changes in other major parameters, including hospitalisation costs and relapse rates. The financial benefit of paroxetine, despite its 15-fold higher acquisition cost compared with imipramine, is attributable to a higher rate of completion of the initial course of therapy and consequent reduced hospitalisation rates.

Cost-effectiveness analysis of treatments for vertebral compression fractures.

Science.gov (United States)

Edidin, Avram A; Ong, Kevin L; Lau, Edmund; Schmier, Jordana K; Kemner, Jason E; Kurtz, Steven M

2012-07-01

Vertebral compression fractures (VCFs) can be treated by nonsurgical management or by minimally invasive surgical treatment including vertebroplasty and balloon kyphoplasty. The purpose of the present study was to characterize the cost to Medicare for treating VCF-diagnosed patients by nonsurgical management, vertebroplasty, or kyphoplasty. We hypothesized that surgical treatments for VCFs using vertebroplasty or kyphoplasty would be a cost-effective alternative to nonsurgical management for the Medicare patient population. Cost per life-year gained for VCF patients in the US Medicare population was compared between operated (kyphoplasty and vertebroplasty) and non-operated patients and between kyphoplasty and vertebroplasty patients, all as a function of patient age and gender. Life expectancy was estimated using a parametric Weibull survival model (adjusted for comorbidities) for 858 978 VCF patients in the 100% Medicare dataset (2005-2008). Median payer costs were identified for each treatment group for up to 3 years following VCF diagnosis, based on 67 018 VCF patients in the 5% Medicare dataset (2005-2008). A discount rate of 3% was used for the base case in the cost-effectiveness analysis, with 0% and 5% discount rates used in sensitivity analyses. After accounting for the differences in median costs and using a discount rate of 3%, the cost per life-year gained for kyphoplasty and vertebroplasty patients ranged from $US1863 to $US6687 and from $US2452 to $US13 543, respectively, compared with non-operated patients. The cost per life-year gained for kyphoplasty compared with vertebroplasty ranged from -$US4878 (cost saving) to $US2763. Among patients for whom surgical treatment was indicated, kyphoplasty was found to be cost effective, and perhaps even cost saving, compared with vertebroplasty. Even for the oldest patients (85 years of age and older), both interventions would be considered cost effective in terms of cost per life-year gained.

SENSITIVITY ANALYSIS OF BUILDING STRUCTURES WITHIN THE SCOPE OF ENERGY, ENVIRONMENT AND INVESTMENT

Directory of Open Access Journals (Sweden)

František Kulhánek

2015-10-01

Full Text Available The primary objective of this paper is to prove the feasibility of sensitivity analysis with dominant weight method for structure parts of envelope of buildings inclusive of energy; ecological and financial assessments, and determination of different designs for same structural part via multi-criteria assessment with theoretical example designs ancillary. Multi-criteria assessment (MCA of different structural designs or in other word alternatives aims to find the best available alternative. The application of sensitivity analysis technique in this paper bases on dominant weighting method. In this research, to choose the best thermal insulation design in the case of that more than one projection, simultaneously, criteria of total thickness (T; heat transfer coefficient (U through the cross section; global warming potential (GWP; acid produce (AP; primary energy content (PEI non renewable and cost per m2 (C are investigated for all designs via sensitivity analysis. Three different designs for external wall (over soil which are convenient with regard to globally suggested energy features for passive house design are investigated through the mentioned six projections. By creating a given set of scenarios; depending upon the importance of each criterion, sensitivity analysis is distributed. As conclusion, uncertainty in the output of model is attributed to different sources in the model input. In this manner, determination of the best available design is achieved. The original outlook and the outlook afterwards the sensitivity analysis are visualized, that enables easily to choose the optimum design within the scope of verified components.

Recommendations for Methicillin-Resistant Staphylococcus aureus Prevention in Adult ICUs: A Cost-Effectiveness Analysis.

Science.gov (United States)

Whittington, Melanie D; Atherly, Adam J; Curtis, Donna J; Lindrooth, Richard C; Bradley, Cathy J; Campbell, Jonathan D

2017-08-01

Patients in the ICU are at the greatest risk of contracting healthcare-associated infections like methicillin-resistant Staphylococcus aureus. This study calculates the cost-effectiveness of methicillin-resistant S aureus prevention strategies and recommends specific strategies based on screening test implementation. A cost-effectiveness analysis using a Markov model from the hospital perspective was conducted to determine if the implementation costs of methicillin-resistant S aureus prevention strategies are justified by associated reductions in methicillin-resistant S aureus infections and improvements in quality-adjusted life years. Univariate and probabilistic sensitivity analyses determined the influence of input variation on the cost-effectiveness. ICU. Hypothetical cohort of adults admitted to the ICU. Three prevention strategies were evaluated, including universal decolonization, targeted decolonization, and screening and isolation. Because prevention strategies have a screening component, the screening test in the model was varied to reflect commonly used screening test categories, including conventional culture, chromogenic agar, and polymerase chain reaction. Universal and targeted decolonization are less costly and more effective than screening and isolation. This is consistent for all screening tests. When compared with targeted decolonization, universal decolonization is cost-saving to cost-effective, with maximum cost savings occurring when a hospital uses more expensive screening tests like polymerase chain reaction. Results were robust to sensitivity analyses. As compared with screening and isolation, the current standard practice in ICUs, targeted decolonization, and universal decolonization are less costly and more effective. This supports updating the standard practice to a decolonization approach.

Contributions to sensitivity analysis and generalized discriminant analysis

International Nuclear Information System (INIS)

Jacques, J.

2005-12-01

Two topics are studied in this thesis: sensitivity analysis and generalized discriminant analysis. Global sensitivity analysis of a mathematical model studies how the output variables of this last react to variations of its inputs. The methods based on the study of the variance quantify the part of variance of the response of the model due to each input variable and each subset of input variables. The first subject of this thesis is the impact of a model uncertainty on results of a sensitivity analysis. Two particular forms of uncertainty are studied: that due to a change of the model of reference, and that due to the use of a simplified model with the place of the model of reference. A second problem was studied during this thesis, that of models with correlated inputs. Indeed, classical sensitivity indices not having significance (from an interpretation point of view) in the presence of correlation of the inputs, we propose a multidimensional approach consisting in expressing the sensitivity of the output of the model to groups of correlated variables. Applications in the field of nuclear engineering illustrate this work. Generalized discriminant analysis consists in classifying the individuals of a test sample in groups, by using information contained in a training sample, when these two samples do not come from the same population. This work extends existing methods in a Gaussian context to the case of binary data. An application in public health illustrates the utility of generalized discrimination models thus defined. (author)

A cost-benefit analysis of varicella vaccination in Aragón.

Science.gov (United States)

Peña Blasco, Guillermo; Blasco Pérez-Aramendía, M Jesús

2017-10-01

Varicella, a contagious and infectious disease that is usually benign in children, may become complicated among adults and vulnerable children and may even be life-threatening. There are effective vaccines. A retrospective study was conducted about costs and resulting hospitalizations related to this disease in the population of Aragón in the 2004-2014 period. Costs were compared to the expenses that would have been incurred if those people had received the vaccine and also to the expenses of vaccinating the 1-year-old population over the entire period. A cost-benefit analysis was done to assess the economic impact of varicella vaccination. Data for the 11-year period were provided by the Autonomous Community of Aragón (Spain) and included annual varicella incidence, hospital discharges of varicella cases, costs of primary health care visits and hospitalizations for each year, costs of each workday as per the minimum annual salary and of drugs used). Capitalized costs were estimated and compared to capitalized expenses of vaccination, and a sensitivity analysis was performed. A benefit-cost ratio of 1.6 was obtained considering that all children who had varicella had been vaccinated and had received a booster dose. A benefit-cost ratio of 1.24 was obtained considering that the vaccine had been administered to every 1-year-old individual at a price of EUR 28.59 per vaccine. Over the 11-year period, 53% of hospitalizations corresponded to children younger than 5 years old. Public campaigns for the immunization of children younger than 4 years old with 2 doses lead to cost savings and are cost-effective because the vaccine price results in a benefit-cost ratio greater than 1. A major reduction is expected in the number of hospitalizations among children aged 3-4 years. Sociedad Argentina de Pediatría

Procedures for uncertainty and sensitivity analysis in repository performance assessment

International Nuclear Information System (INIS)

Poern, K.; Aakerlund, O.

1985-10-01

The objective of the project was mainly a literature study of available methods for the treatment of parameter uncertainty propagation and sensitivity aspects in complete models such as those concerning geologic disposal of radioactive waste. The study, which has run parallel with the development of a code package (PROPER) for computer assisted analysis of function, also aims at the choice of accurate, cost-affective methods for uncertainty and sensitivity analysis. Such a choice depends on several factors like the number of input parameters, the capacity of the model and the computer reresources required to use the model. Two basic approaches are addressed in the report. In one of these the model of interest is directly simulated by an efficient sampling technique to generate an output distribution. Applying the other basic method the model is replaced by an approximating analytical response surface, which is then used in the sampling phase or in moment matching to generate the output distribution. Both approaches are illustrated by simple examples in the report. (author)

ADGEN: a system for automated sensitivity analysis of predictive models

International Nuclear Information System (INIS)

Pin, F.G.; Horwedel, J.E.; Oblow, E.M.; Lucius, J.L.

1987-01-01

A system that can automatically enhance computer codes with a sensitivity calculation capability is presented. With this new system, named ADGEN, rapid and cost-effective calculation of sensitivities can be performed in any FORTRAN code for all input data or parameters. The resulting sensitivities can be used in performance assessment studies related to licensing or interactions with the public to systematically and quantitatively prove the relative importance of each of the system parameters in calculating the final performance results. A general procedure calling for the systematic use of sensitivities in assessment studies is presented. The procedure can be used in modeling and model validation studies to avoid over modeling, in site characterization planning to avoid over collection of data, and in performance assessments to determine the uncertainties on the final calculated results. The added capability to formally perform the inverse problem, i.e., to determine the input data or parameters on which to focus to determine the input data or parameters on which to focus additional research or analysis effort in order to improve the uncertainty of the final results, is also discussed. 7 references, 2 figures

Cost analysis of measles in refugees arriving at Los Angeles International Airport from Malaysia.

Science.gov (United States)

Coleman, Margaret S; Burke, Heather M; Welstead, Bethany L; Mitchell, Tarissa; Taylor, Eboni M; Shapovalov, Dmitry; Maskery, Brian A; Joo, Heesoo; Weinberg, Michelle

2017-05-04

Background On August 24, 2011, 31 US-bound refugees from Kuala Lumpur, Malaysia (KL) arrived in Los Angeles. One of them was diagnosed with measles post-arrival. He exposed others during a flight, and persons in the community while disembarking and seeking medical care. As a result, 9 cases of measles were identified. Methods We estimated costs of response to this outbreak and conducted a comparative cost analysis examining what might have happened had all US-bound refugees been vaccinated before leaving Malaysia. Results State-by-state costs differed and variously included vaccination, hospitalization, medical visits, and contact tracing with costs ranging from $621 to $35,115. The total of domestic and IOM Malaysia reported costs for US-bound refugees were $137,505 [range: $134,531 - $142,777 from a sensitivity analysis]. Had all US-bound refugees been vaccinated while in Malaysia, it would have cost approximately $19,646 and could have prevented 8 measles cases. Conclusion A vaccination program for US-bound refugees, supporting a complete vaccination for US-bound refugees, could improve refugees' health, reduce importations of vaccine-preventable diseases in the United States, and avert measles response activities and costs.

Cost-effectiveness analysis of HLA-B*5801 testing in preventing allopurinol-induced SJS/TEN in Thai population.

Directory of Open Access Journals (Sweden)

Surasak Saokaew

Full Text Available BACKGROUND: Stevens-Johnson syndrome (SJS and Toxic Epidermal Necrolysis (TEN, caused by allopurinol therapy, are strongly associated with the human leukocyte antigen (HLA, HLA-B*5801. Identification of HLA-B*5801 genotype before prescribing allopurinol offers the possibility of avoiding allopurinol-induced SJS/TEN. As there is a paucity of evidence about economic value of such testing, this study aims to determine the cost-effectiveness of HLA-B*5801 testing compared with usual care (no genetic testing before allopurinol administration in Thailand. METHODS AND FINDING: A decision analytical and Markov model was used to estimate life time costs and outcomes represented as quality adjusted life years (QALYs gained. The model was populated with relevant information of the association between gene and allopurinol-induced SJS/TEN, test characteristics, costs, and epidemiologic data for Thailand from a societal perspective. Input data were obtained from the literature and a retrospective database analysis. The results were expressed as incremental cost per QALY gained. A base-case analysis was performed for patients at age 30. A series of sensitivity analyses including scenario, one-way, and probabilistic sensitivity analyses were constructed to explore the robustness of the findings. Based on a hypothetical cohort of 1,000 patients, the incremental total cost was 923,919 THB (USD 29,804 and incremental QALY was 5.89 with an ICER of 156,937.04 THB (USD 5,062 per QALY gained. The cost of gout management, incidence of SJS/TEN, case fatality rate of SJS/TEN, and cost of genetic testing are considered very influential parameters on the cost-effectiveness value of HLA-B*5801 testing. CONCLUSIONS: The genetic testing for HLA-B*5801 before allopurinol administration is considered a highly potential cost-effective intervention in Thailand. The findings are sensitive to a number of factors. In addition to cost-effectiveness findings, consideration of other

Cost-Effectiveness Analysis of Regorafenib for Metastatic Colorectal Cancer.

Science.gov (United States)

Goldstein, Daniel A; Ahmad, Bilal B; Chen, Qiushi; Ayer, Turgay; Howard, David H; Lipscomb, Joseph; El-Rayes, Bassel F; Flowers, Christopher R

2015-11-10

Regorafenib is a standard-care option for treatment-refractory metastatic colorectal cancer that increases median overall survival by 6 weeks compared with placebo. Given this small incremental clinical benefit, we evaluated the cost-effectiveness of regorafenib in the third-line setting for patients with metastatic colorectal cancer from the US payer perspective. We developed a Markov model to compare the cost and effectiveness of regorafenib with those of placebo in the third-line treatment of metastatic colorectal cancer. Health outcomes were measured in life-years and quality-adjusted life-years (QALYs). Drug costs were based on Medicare reimbursement rates in 2014. Model robustness was addressed in univariable and probabilistic sensitivity analyses. Regorafenib provided an additional 0.04 QALYs (0.13 life-years) at a cost of $40,000, resulting in an incremental cost-effectiveness ratio of $900,000 per QALY. The incremental cost-effectiveness ratio for regorafenib was > $550,000 per QALY in all of our univariable and probabilistic sensitivity analyses. Regorafenib provides minimal incremental benefit at high incremental cost per QALY in the third-line management of metastatic colorectal cancer. The cost-effectiveness of regorafenib could be improved by the use of value-based pricing. © 2015 by American Society of Clinical Oncology.

An Analytical Cost Estimation Procedure

National Research Council Canada - National Science Library

Jayachandran, Toke

1999-01-01

Analytical procedures that can be used to do a sensitivity analysis of a cost estimate, and to perform tradeoffs to identify input values that can reduce the total cost of a project, are described in the report...

Instructional Cost Analysis: History and Present Inadequacies.

Science.gov (United States)

Humphrey, David A.

The cost analysis of instruction is conducted according to principles of teaching and learning that have often become historically dated. Using today's costing systems prevents determination of whether cost effectiveness actually exists. The patterns of instruction in higher education and the systems employed for instructional cost analysis are…

Basal Insulin Regimens for Adults with Type 1 Diabetes Mellitus: A Cost-Utility Analysis.

Science.gov (United States)

Dawoud, Dalia; Fenu, Elisabetta; Higgins, Bernard; Wonderling, David; Amiel, Stephanie A

2017-12-01

To assess the cost-effectiveness of basal insulin regimens for adults with type 1 diabetes mellitus in England. A cost-utility analysis was conducted in accordance with the National Institute for Health and Care Excellence reference case. The UK National Health Service and personal and social services perspective was used and a 3.5% discount rate was applied for both costs and outcomes. Relative effectiveness estimates were based on a systematic review of published trials and a Bayesian network meta-analysis. The IMS CORE Diabetes Model was used, in which net monetary benefit (NMB) was calculated using a threshold of £20,000 per quality-adjusted life-year (QALY) gained. A wide range of sensitivity analyses were conducted. Insulin detemir (twice daily) [iDet (bid)] had the highest mean QALY gain (11.09 QALYs) and NMB (£181,456) per patient over the model time horizon. Compared with the lowest cost strategy (insulin neutral protamine Hagedorn once daily), it had an incremental cost-effectiveness ratio of £7844/QALY gained. Insulin glargine (od) [iGlarg (od)] and iDet (od) were ranked as second and third, with NMBs of £180,893 and £180,423, respectively. iDet (bid) remained the most cost-effective treatment in all the sensitivity analyses performed except when high doses were assumed (>30% increment compared with other regimens), where iGlarg (od) ranked first. iDet (bid) is the most cost-effective regimen, providing the highest QALY gain and NMB. iGlarg (od) and iDet (od) are possible options for those for whom the iDet (bid) regimen is not acceptable or does not achieve required glycemic control. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

24 CFR 965.402 - Benefit/cost analysis.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Benefit/cost analysis. 965.402...-Owned Projects § 965.402 Benefit/cost analysis. (a) A benefit/cost analysis shall be made to determine... (Continued) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN...

Comparing surgical trays with redundant instruments with trays with reduced instruments: a cost analysis.

Science.gov (United States)

John-Baptiste, A; Sowerby, L J; Chin, C J; Martin, J; Rotenberg, B W

2016-01-01

When prearranged standard surgical trays contain instruments that are repeatedly unused, the redundancy can result in unnecessary health care costs. Our objective was to estimate potential savings by performing an economic evaluation comparing the cost of surgical trays with redundant instruments with surgical trays with reduced instruments ("reduced trays"). We performed a cost-analysis from the hospital perspective over a 1-year period. Using a mathematical model, we compared the direct costs of trays containing redundant instruments to reduced trays for 5 otolaryngology procedures. We incorporated data from several sources including local hospital data on surgical volume, the number of instruments on redundant and reduced trays, wages of personnel and time required to pack instruments. From the literature, we incorporated instrument depreciation costs and the time required to decontaminate an instrument. We performed 1-way sensitivity analyses on all variables, including surgical volume. Costs were estimated in 2013 Canadian dollars. The cost of redundant trays was $21 806 and the cost of reduced trays was $8803, for a 1-year cost saving of $13 003. In sensitivity analyses, cost savings ranged from $3262 to $21 395, based on the surgical volume at the institution. Variation in surgical volume resulted in a wider range of estimates, with a minimum of $3253 for low-volume to a maximum of $52 012 for high-volume institutions. Our study suggests moderate savings may be achieved by reducing surgical tray redundancy and, if applied to other surgical specialties, may result in savings to Canadian health care systems.

Cost and performance analysis of physical security systems

International Nuclear Information System (INIS)

Hicks, M.J.; Yates, D.; Jago, W.H.; Phillips, A.W.

1998-04-01

Analysis of cost and performance of physical security systems can be a complex, multi-dimensional problem. There are a number of point tools that address various aspects of cost and performance analysis. Increased interest in cost tradeoffs of physical security alternatives has motivated development of an architecture called Cost and Performance Analysis (CPA), which takes a top-down approach to aligning cost and performance metrics. CPA incorporates results generated by existing physical security system performance analysis tools, and utilizes an existing cost analysis tool. The objective of this architecture is to offer comprehensive visualization of complex data to security analysts and decision-makers

Specifying the ovarian cancer risk threshold of 'premenopausal risk-reducing salpingo-oophorectomy' for ovarian cancer prevention: a cost-effectiveness analysis.

Science.gov (United States)

Manchanda, Ranjit; Legood, Rosa; Antoniou, Antonis C; Gordeev, Vladimir S; Menon, Usha

2016-09-01

Risk-reducing salpingo-oophorectomy (RRSO) is the most effective intervention to prevent ovarian cancer (OC). It is only available to high-risk women with >10% lifetime OC risk. This threshold has not been formally tested for cost-effectiveness. To specify the OC risk thresholds for RRSO being cost-effective for preventing OC in premenopausal women. The costs as well as effects of surgical prevention ('RRSO') were compared over a lifetime with 'no RRSO' using a decision analysis model. RRSO was undertaken in premenopausal women >40 years. The model was evaluated at lifetime OC risk levels: 2%, 4%, 5%, 6%, 8% and 10%. Costs and outcomes are discounted at 3.5%. Uncertainty in the model was assessed using both deterministic sensitivity analysis and probabilistic sensitivity analysis (PSA). Outcomes included in the analyses were OC, breast cancer (BC) and additional deaths from coronary heart disease. Total costs and effects were estimated in terms of quality-adjusted life-years (QALYs); incidence of OC and BC; as well as incremental cost-effectiveness ratio (ICER). Published literature, Nurses Health Study, British National Formulary, Cancer Research UK, National Institute for Health and Care Excellence guidelines and National Health Service reference costs. The time horizon is lifetime and perspective: payer. Premenopausal RRSO is cost-effective at 4% OC risk (life expectancy gained=42.7 days, ICER=£19 536/QALY) with benefits largely driven by reduction in BC risk. RRSO remains cost-effective at >8.2% OC risk without hormone replacement therapy (ICER=£29 071/QALY, life expectancy gained=21.8 days) or 6%if BC risk reduction=0 (ICER=£27 212/QALY, life expectancy gained=35.3 days). Sensitivity analysis indicated results are not impacted much by costs of surgical prevention or treatment of OC/ BC or cardiovascular disease. However, results were sensitive to RRSO utility scores. Additionally, 37%, 61%, 74%, 84%, 96% and 99.5% simulations on PSA are cost

Cost-effectiveness analysis of main diagnosis tools in women with overactive bladder. Clinical history, micturition diary and urodynamic study.

Science.gov (United States)

López-Fando, L; Carracedo, D; Jiménez, M; Gómez de Vicente, J M; Martínez, L; Gómez-Cañizo, C; Gómez, V; Burgos, F J

2015-01-01

The aim of the present clinical research is to analyze, in the light of the best scientific evidence, the performance and the cost of the main diagnostic tools for overactive bladder (OAB). It is an exploratory transversal study in which 199 women diagnosed of OAB between 2006 and 2008 were selected and underwent to following prospective analyses: physical examination, urine analysis, micturition diary (MD) and urodynamic study (UDS). A percentage of 80% was assumed as highly sensitive and a diagnostic difference among tests of 10% would be considered clinically relevant. Tests' sensitivity for diagnosis of OAB was statistically established by two ways: isolated and combined. Besides, the direct and indirect costs of these tests performance were conducted. Cost-effectiveness study of clinical history (CH), MD and US for the diagnosis of OAB was performed. Overall sensitivity for OAB diagnosis is low for the 3 tests used in isolated way, whilst the combination of any two tests shows good overall sensitivity. The combination of CH and MD has appeared as the most cost-effective alternative to OAB diagnosis. For OAB diagnosis, CH-DM combination shows the same sensitivity than the association of either of them with the UDS, but unlike to these, it shows the lowest cost. Copyright © 2013 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Cost-effectiveness of two versus three or more doses of intermittent preventive treatment for malaria during pregnancy in sub-Saharan Africa: a modelling study of meta-analysis and cost data.

Science.gov (United States)

Fernandes, Silke; Sicuri, Elisa; Kayentao, Kassoum; van Eijk, Anne Maria; Hill, Jenny; Webster, Jayne; Were, Vincent; Akazili, James; Madanitsa, Mwayi; ter Kuile, Feiko O; Hanson, Kara

2015-03-01

In 2012, WHO changed its recommendation for intermittent preventive treatment of malaria during pregnancy (IPTp) from two doses to monthly doses of sulfadoxine-pyrimethamine during the second and third trimesters, but noted the importance of a cost-effectiveness analysis to lend support to the decision of policy makers. We therefore estimated the incremental cost-effectiveness of IPTp with three or more (IPTp-SP3+) versus two doses of sulfadoxine-pyrimethamine (IPTp-SP2). For this analysis, we used data from a 2013 meta-analysis of seven studies in sub-Saharan Africa. We developed a decision tree model with a lifetime horizon. We analysed the base case from a societal perspective. We did deterministic and probabilistic sensitivity analyses with appropriate parameter ranges and distributions for settings with low, moderate, and high background risk of low birthweight, and did a separate analysis for HIV-negative women. Parameters in the model were obtained for all countries included in the original meta-analysis. We did simulations in hypothetical cohorts of 1000 pregnant women receiving either IPTp-SP3+ or IPTp-SP2. We calculated disability-adjusted life-years (DALYs) for low birthweight, severe to moderate anaemia, and clinical malaria. We calculated cost estimates from data obtained in observational studies, exit surveys, and from public procurement databases. We give financial and economic costs in constant 2012 US$. The main outcome measure was the incremental cost per DALY averted. The delivery of IPTp-SP3+ to 1000 pregnant women averted 113·4 DALYs at an incremental cost of $825·67 producing an incremental cost-effectiveness ratio (ICER) of $7·28 per DALY averted. The results remained robust in the deterministic sensitivity analysis. In the probabilistic sensitivity analyses, the ICER was $7·7 per DALY averted for moderate risk of low birthweight, $19·4 per DALY averted for low risk, and $4·0 per DALY averted for high risk. The ICER for HIV

Object-sensitive Type Analysis of PHP

NARCIS (Netherlands)

Van der Hoek, Henk Erik; Hage, J

2015-01-01

In this paper we develop an object-sensitive type analysis for PHP, based on an extension of the notion of monotone frameworks to deal with the dynamic aspects of PHP, and following the framework of Smaragdakis et al. for object-sensitive analysis. We consider a number of instantiations of the

Cost-effectiveness analysis of fecal microbiota transplantation for recurrent Clostridium difficile infection.

Science.gov (United States)

Varier, Raghu U; Biltaji, Eman; Smith, Kenneth J; Roberts, Mark S; Kyle Jensen, M; LaFleur, Joanne; Nelson, Richard E

2015-04-01

Clostridium difficile infection (CDI) places a high burden on the US healthcare system. Recurrent CDI (RCDI) occurs frequently. Recently proposed guidelines from the American College of Gastroenterology (ACG) and the American Gastroenterology Association (AGA) include fecal microbiota transplantation (FMT) as a therapeutic option for RCDI. The purpose of this study was to estimate the cost-effectiveness of FMT compared with vancomycin for the treatment of RCDI in adults, specifically following guidelines proposed by the ACG and AGA. We constructed a decision-analytic computer simulation using inputs from the published literature to compare the standard approach using tapered vancomycin to FMT for RCDI from the third-party payer perspective. Our effectiveness measure was quality-adjusted life years (QALYs). Because simulated patients were followed for 90 days, discounting was not necessary. One-way and probabilistic sensitivity analyses were performed. Base-case analysis showed that FMT was less costly ($1,669 vs $3,788) and more effective (0.242 QALYs vs 0.235 QALYs) than vancomycin for RCDI. One-way sensitivity analyses showed that FMT was the dominant strategy (both less expensive and more effective) if cure rates for FMT and vancomycin were ≥70% and cost of FMT was cost-saving intervention in managing RCDI. Implementation of FMT for RCDI may help decrease the economic burden to the healthcare system.

Cost-effectiveness analysis of vaccination against rotavirus with RIX4414 in France.

Science.gov (United States)

Standaert, Baudouin; Parez, Nathalie; Tehard, Bertrand; Colin, Xavier; Detournay, Bruno

2008-01-01

It is estimated that annually 300 000 cases of rotavirus-induced gastroenteritis (RVGE) occur in children aged up to 5 years in France. A two-dose vaccine against rotavirus infection (RIX4414; Rotarix, GlaxoSmithKline), has been shown to be highly effective against severe RVGE. This study evaluated the cost effectiveness of general vaccination against rotavirus using RIX4414 in France. A Markov model simulated RVGE events and the associated outcomes and costs relating to general vaccination of infants against rotavirus infection using RIX4414 (Rotarix) in a birth cohort of children aged up to 5 years in France with a combined adjustment for age distribution with the seasonality of the infection. Costs and outcomes were estimated from a limited societal perspective, including direct medical costs paid out of pocket or by third-party payers, as well as the proportion of direct medical costs reimbursed by the health authorities. Indirect costs were not included in the base-case analysis. The primary outcome measure was the incremental cost per QALY. Vaccination with RIX4414 incurred an incremental cost of 44 583 Euro per QALY at a public price of 57 Euro per vaccine dose. Univariate sensitivity analyses showed that the parameters with the largest influence on the results were the transition probabilities of severe diarrhoea, seeking medical advice and emergency visits, utility scores of diarrhoea (mild) in children and infants, and the discount rate for benefits. Probabilistic multivariate sensitivity analysis confirmed these results. The acceptability curve indicated that 94% of the results were under an informal threshold of 50 000 Euro per QALY. Comparing our results with those of a recently published study using pooled data for two rotavirus vaccine products in France, the main differences are explained by differences in model structure and in data input values. They include a different age distribution of the infection, shorter duration of the at-risk period (3

Surveillance-guided selective digestive decontamination of carbapenem-resistant Enterobacteriaceae in the intensive care unit: A cost-effectiveness analysis.

Science.gov (United States)

You, Joyce H S; Li, Hong-Kiu; Ip, Margaret

2018-03-01

Clinical findings have shown effectiveness and safety of selective digestive decontamination (SDD) for eradication of carbapenem-resistant Enterobacteriaceae (CRE) in high-risk carriers. We aimed to evaluate the cost-effectiveness of SDD guided by CRE surveillance in the intensive care unit (ICU). Outcomes of surveillance-guided SDD (test-guided SDD) and no screening (control) in the ICU were compared by Markov model simulations. Model outcomes were CRE infection and mortality rates, direct costs, and quality-adjusted life year (QALY) loss. Model inputs were estimated from clinical literature. Sensitivity analyses were conducted to examine the robustness of base case results. Test-guided SDD reduced infection (4.8% vs 5.0%) and mortality (1.8% vs 2.1%) rates at a higher cost ($1,102 vs $1,074) than the control group in base case analysis, respectively. Incremental cost per QALY saved (incremental cost-effectiveness ratio [ICER]) by the test-guided SDD group was $557 per QALY. Probabilistic sensitivity analysis showed that test-guided SDD was effective in saving QALYs in 100% of 10,000 Monte Carlo simulations, and cost-saving 59.1% of time. The remaining 40.9% of simulations found SDD to be effective at an additional cost, with ICERs accepted as cost-effective per the willingness-to-pay threshold. Surveillance-guided SDD appears to be cost-effective in reducing CRE infection and mortality with QALYs saved. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Cost analysis of in vitro fertilization.

Science.gov (United States)

Stern, Z; Laufer, N; Levy, R; Ben-Shushan, D; Mor-Yosef, S

1995-08-01

In vitro fertilization (IVF) has become a routine tool in the arsenal of infertility treatments. Assisted reproductive techniques are expensive, as reflected by the current "take home baby" rate of about 15% per cycle, implying the need for repeated attempts until success is achieved. Israel, today is facing a major change in its health care system, including the necessity to define a national package of health care benefits. The issue of infertility and whether its treatment should be part of the "health basket" is in dispute. Therefore an exact cost analysis of IVF is important. Since the cost of an IVF cycle varies dramatically between countries, we sought an exact breakdown of the different components of the costs involved in an IVF cycle and in achieving an IVF child in Israel. The key question is not how much we spend on IVF cycles but what is the cost of a successful outcome, i.e., a healthy child. This study intends to answer this question, and to give the policy makers, at various levels of the health care system, a crucial tool for their decision-making process. The cost analysis includes direct and indirect costs. The direct costs are divided into fixed costs (labor, equipment, maintenance, depreciation, and overhead) and variable costs (laboratory tests, chemicals, disposable supplies, medications, and loss of working days by the couples). The indirect costs are the costs of premature IVF babies, hospitalization of the IVF pregnant women in a high risk unit, and the cost of complications of the procedure. According to our economic analysis, an IVF cycle in Israel costs $2,560, of which fixed costs are about 50%. The cost of a "take home baby" is $19,267, including direct and indirect costs.

Seasonal influenza vaccination for children in Thailand: a cost-effectiveness analysis.

Science.gov (United States)

Meeyai, Aronrag; Praditsitthikorn, Naiyana; Kotirum, Surachai; Kulpeng, Wantanee; Putthasri, Weerasak; Cooper, Ben S; Teerawattananon, Yot

2015-05-01

Seasonal influenza is a major cause of mortality worldwide. Routine immunization of children has the potential to reduce this mortality through both direct and indirect protection, but has not been adopted by any low- or middle-income countries. We developed a framework to evaluate the cost-effectiveness of influenza vaccination policies in developing countries and used it to consider annual vaccination of school- and preschool-aged children with either trivalent inactivated influenza vaccine (TIV) or trivalent live-attenuated influenza vaccine (LAIV) in Thailand. We also compared these approaches with a policy of expanding TIV coverage in the elderly. We developed an age-structured model to evaluate the cost-effectiveness of eight vaccination policies parameterized using country-level data from Thailand. For policies using LAIV, we considered five different age groups of children to vaccinate. We adopted a Bayesian evidence-synthesis framework, expressing uncertainty in parameters through probability distributions derived by fitting the model to prospectively collected laboratory-confirmed influenza data from 2005-2009, by meta-analysis of clinical trial data, and by using prior probability distributions derived from literature review and elicitation of expert opinion. We performed sensitivity analyses using alternative assumptions about prior immunity, contact patterns between age groups, the proportion of infections that are symptomatic, cost per unit vaccine, and vaccine effectiveness. Vaccination of children with LAIV was found to be highly cost-effective, with incremental cost-effectiveness ratios between about 2,000 and 5,000 international dollars per disability-adjusted life year averted, and was consistently preferred to TIV-based policies. These findings were robust to extensive sensitivity analyses. The optimal age group to vaccinate with LAIV, however, was sensitive both to the willingness to pay for health benefits and to assumptions about contact

Brain network analysis: separating cost from topology using cost-integration.

Directory of Open Access Journals (Sweden)

Cedric E Ginestet

Full Text Available A statistically principled way of conducting brain network analysis is still lacking. Comparison of different populations of brain networks is hard because topology is inherently dependent on wiring cost, where cost is defined as the number of edges in an unweighted graph. In this paper, we evaluate the benefits and limitations associated with using cost-integrated topological metrics. Our focus is on comparing populations of weighted undirected graphs that differ in mean association weight, using global efficiency. Our key result shows that integrating over cost is equivalent to controlling for any monotonic transformation of the weight set of a weighted graph. That is, when integrating over cost, we eliminate the differences in topology that may be due to a monotonic transformation of the weight set. Our result holds for any unweighted topological measure, and for any choice of distribution over cost levels. Cost-integration is therefore helpful in disentangling differences in cost from differences in topology. By contrast, we show that the use of the weighted version of a topological metric is generally not a valid approach to this problem. Indeed, we prove that, under weak conditions, the use of the weighted version of global efficiency is equivalent to simply comparing weighted costs. Thus, we recommend the reporting of (i differences in weighted costs and (ii differences in cost-integrated topological measures with respect to different distributions over the cost domain. We demonstrate the application of these techniques in a re-analysis of an fMRI working memory task. We also provide a Monte Carlo method for approximating cost-integrated topological measures. Finally, we discuss the limitations of integrating topology over cost, which may pose problems when some weights are zero, when multiplicities exist in the ranks of the weights, and when one expects subtle cost-dependent topological differences, which could be masked by cost-integration.

Brain Network Analysis: Separating Cost from Topology Using Cost-Integration

Science.gov (United States)

Ginestet, Cedric E.; Nichols, Thomas E.; Bullmore, Ed T.; Simmons, Andrew

2011-01-01

A statistically principled way of conducting brain network analysis is still lacking. Comparison of different populations of brain networks is hard because topology is inherently dependent on wiring cost, where cost is defined as the number of edges in an unweighted graph. In this paper, we evaluate the benefits and limitations associated with using cost-integrated topological metrics. Our focus is on comparing populations of weighted undirected graphs that differ in mean association weight, using global efficiency. Our key result shows that integrating over cost is equivalent to controlling for any monotonic transformation of the weight set of a weighted graph. That is, when integrating over cost, we eliminate the differences in topology that may be due to a monotonic transformation of the weight set. Our result holds for any unweighted topological measure, and for any choice of distribution over cost levels. Cost-integration is therefore helpful in disentangling differences in cost from differences in topology. By contrast, we show that the use of the weighted version of a topological metric is generally not a valid approach to this problem. Indeed, we prove that, under weak conditions, the use of the weighted version of global efficiency is equivalent to simply comparing weighted costs. Thus, we recommend the reporting of (i) differences in weighted costs and (ii) differences in cost-integrated topological measures with respect to different distributions over the cost domain. We demonstrate the application of these techniques in a re-analysis of an fMRI working memory task. We also provide a Monte Carlo method for approximating cost-integrated topological measures. Finally, we discuss the limitations of integrating topology over cost, which may pose problems when some weights are zero, when multiplicities exist in the ranks of the weights, and when one expects subtle cost-dependent topological differences, which could be masked by cost-integration. PMID:21829437

Sensitivity analysis of numerical results of one- and two-dimensional advection-diffusion problems

International Nuclear Information System (INIS)

Motoyama, Yasunori; Tanaka, Nobuatsu

2005-01-01

Numerical simulation has been playing an increasingly important role in the fields of science and engineering. However, every numerical result contains errors such as modeling, truncation, and computing errors, and the magnitude of the errors that are quantitatively contained in the results is unknown. This situation causes a large design margin in designing by analyses and prevents further cost reduction by optimizing design. To overcome this situation, we developed a new method to numerically analyze the quantitative error of a numerical solution by using the sensitivity analysis method and modified equation approach. If a reference case of typical parameters is calculated once by this method, then no additional calculation is required to estimate the results of other numerical parameters such as those of parameters with higher resolutions. Furthermore, we can predict the exact solution from the sensitivity analysis results and can quantitatively evaluate the error of numerical solutions. Since the method incorporates the features of the conventional sensitivity analysis method, it can evaluate the effect of the modeling error as well as the truncation error. In this study, we confirm the effectiveness of the method through some numerical benchmark problems of one- and two-dimensional advection-diffusion problems. (author)

Ethical sensitivity in professional practice: concept analysis.

Science.gov (United States)

Weaver, Kathryn; Morse, Janice; Mitcham, Carl

2008-06-01

This paper is a report of a concept analysis of ethical sensitivity. Ethical sensitivity enables nurses and other professionals to respond morally to the suffering and vulnerability of those receiving professional care and services. Because of its significance to nursing and other professional practices, ethical sensitivity deserves more focused analysis. A criteria-based method oriented toward pragmatic utility guided the analysis of 200 papers and books from the fields of nursing, medicine, psychology, dentistry, clinical ethics, theology, education, law, accounting or business, journalism, philosophy, political and social sciences and women's studies. This literature spanned 1970 to 2006 and was sorted by discipline and concept dimensions and examined for concept structure and use across various contexts. The analysis was completed in September 2007. Ethical sensitivity in professional practice develops in contexts of uncertainty, client suffering and vulnerability, and through relationships characterized by receptivity, responsiveness and courage on the part of professionals. Essential attributes of ethical sensitivity are identified as moral perception, affectivity and dividing loyalties. Outcomes include integrity preserving decision-making, comfort and well-being, learning and professional transcendence. Our findings promote ethical sensitivity as a type of practical wisdom that pursues client comfort and professional satisfaction with care delivery. The analysis and resulting model offers an inclusive view of ethical sensitivity that addresses some of the limitations with prior conceptualizations.

Multitarget global sensitivity analysis of n-butanol combustion.

Science.gov (United States)

Zhou, Dingyu D Y; Davis, Michael J; Skodje, Rex T

2013-05-02

A model for the combustion of butanol is studied using a recently developed theoretical method for the systematic improvement of the kinetic mechanism. The butanol mechanism includes 1446 reactions, and we demonstrate that it is straightforward and computationally feasible to implement a full global sensitivity analysis incorporating all the reactions. In addition, we extend our previous analysis of ignition-delay targets to include species targets. The combination of species and ignition targets leads to multitarget global sensitivity analysis, which allows for a more complete mechanism validation procedure than we previously implemented. The inclusion of species sensitivity analysis allows for a direct comparison between reaction pathway analysis and global sensitivity analysis.

Cost-effectiveness analysis of tenofovir disoproxil fumarate for treatment of chronic hepatitis B in China.

Science.gov (United States)

Ke, Weixia; Zhang, Chi; Liu, Li; Gao, Yanhui; Yao, Zhenjiang; Ye, Xiaohua; Zhou, Shudong; Yang, Yi

2016-11-01

Tenofovir disoproxil fumarate (TDF) is newly available for treatment of chronic hepatitis B patients in China. To date, no study has been conducted to examine the cost-effectiveness of this treatment. The aim of this study was to estimate the cost-effectiveness of TDF versus four oral nucleos(t)ide analogs [lamivudine (LAM), adefovir (ADV), telbivudine (LdT), and entecavir (ETV)] and from a pharmacoeconomic perspective to assess current drug pricing for TDF. Based on Chinese healthcare perspectives, a Markov model was applied to simulate the lifetime (40-year time span) costs and quality-adjusted life-years (QALYs) for five different monotherapy strategies. Two kinds of rescue combination strategies (base-case: LAM + ADV then ETV + ADV; alternative: directly using ETV + ADV) were separately considered for treatment of patients refractory to monotherapy. Model parameters (including disease transition, cost, and utility) were obtained from previous Chinese population studies. Both branded and generic drugs were separately analyzed. Study model uncertainties were assessed by one-way and probabilistic sensitivity analyses. Two-way sensitivity analysis was used to explore uncertainties between efficacy and price of TDF. In the base-case analysis, the lowest lifetime cost and the best cost-effectiveness ratio were obtained by ETV, which was considered the reference treatment. LAM, ADV, and LdT treatments had significantly greater costs and lower efficacies. Compared to ETV, TDF was more effective but also more expensive. The incremental cost-effectiveness ratios of TDF versus ETV were much higher than the willing-to-pay threshold of $20,466 US dollars (USD) per QALY gained (3 × gross domestic product per capita of China, 2014). TDF would be the most cost-effective strategy if the annual cost did not exceed $2260 USD and $1600 USD for branded and generic drugs, respectively. For Chinese chronic hepatitis B patients, ETV is still the most cost

Cost-effectiveness analysis of infant feeding strategies to prevent ...

African Journals Online (AJOL)

Changing feeding practices is beneficial, depending on context. Breastfeeding is dominant (less costly, more effective) in rural settings, whilst formula feeding is a dominant strategy in urban settings. Cost-effectiveness was most sensitive to proportion of women on lifelong antiretroviral therapy (ART) and infant mortality rate ...

A cost-benefit analysis on the specialization in departments of obstetrics and gynecology in Japan.

Science.gov (United States)

Shen, Junyi; Fukui, On; Hashimoto, Hiroyuki; Nakashima, Takako; Kimura, Tadashi; Morishige, Kenichiro; Saijo, Tatsuyoshi

2012-03-27

In April 2008, the specialization in departments of obstetrics and gynecology was conducted in Sennan area of Osaka prefecture in Japan, which aims at solving the problems of regional provision of obstetrical service. Under this specialization, the departments of obstetrics and gynecology in two city hospitals were combined as one medical center, whilst one hospital is in charge of the department of gynecology and the other one operates the department of obstetrics. In this paper, we implement a cost-benefit analysis to evaluate the validity of this specialization. The benefit-cost ratio is estimated at 1.367 under a basic scenario, indicating that the specialization can generate a net benefit. In addition, with a consideration of different kinds of uncertainty in the future, a number of sensitivity analyses are conducted. The results of these sensitivity analyses suggest that the specialization is valid in the sense that all the estimated benefit-cost ratios are above 1.0 in any case.

Primary treatments for clinically localised prostate cancer: a comprehensive lifetime cost-utility analysis.

Science.gov (United States)

Cooperberg, Matthew R; Ramakrishna, Naren R; Duff, Steven B; Hughes, Kathleen E; Sadownik, Sara; Smith, Joseph A; Tewari, Ashutosh K

2013-03-01

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Multiple treatment alternatives exist for localised prostate cancer, with few high-quality studies directly comparing their comparative effectiveness and costs. The present study is the most comprehensive cost-effectiveness analysis to date for localised prostate cancer, conducted with a lifetime horizon and accounting for survival, health-related quality-of-life, and cost impact of secondary treatments and other downstream events, as well as primary treatment choices. The analysis found minor differences, generally slightly favouring surgical methods, in quality-adjusted life years across treatment options. However, radiation therapy (RT) was consistently more expensive than surgery, and some alternatives, e.g. intensity-modulated RT for low-risk disease, were dominated - that is, both more expensive and less effective than competing alternatives. To characterise the costs and outcomes associated with radical prostatectomy (open, laparoscopic, or robot-assisted) and radiation therapy (RT: dose-escalated three-dimensional conformal RT, intensity-modulated RT, brachytherapy, or combination), using a comprehensive, lifetime decision analytical model. A Markov model was constructed to follow hypothetical men with low-, intermediate-, and high-risk prostate cancer over their lifetimes after primary treatment; probabilities of outcomes were based on an exhaustive literature search yielding 232 unique publications. In each Markov cycle, patients could have remission, recurrence, salvage treatment, metastasis, death from prostate cancer, and death from other causes. Utilities for each health state were determined, and disutilities were applied for complications and toxicities of treatment. Costs were determined from the USA payer perspective, with incorporation of patient costs in a sensitivity analysis. Differences across treatments in quality-adjusted life years across methods were modest, ranging from 10.3 to

Custo e análise de sensibilidade na produção de silagem = Cost and sensitivity analysis in the production of silage

Directory of Open Access Journals (Sweden)

Glauber dos Santos

2017-01-01

miscellaneous expenses. The total production cost of corn silage in the 15/16 year crop was R$ 317.30 per ton of dry matter or R$ 104.71 per ton of green matter. The inputs (seeds, fertilizers and pesticides were the most representative items in the cost, followed by harvesting and silage, planting and cultivation, and soil preparation. The sensitivity analysis shows that the cost is 1.92 times more considering different productivity values and percentages of loss, being the lowest cost R$ 81.57 and the highest R$ 157.32.

Research of the cost-benefit analysis for FR cycle research and development. The annual report of the FY 2001

International Nuclear Information System (INIS)

Shiotani, Hiroki; Shinoda, Yoshihiko; Hirao, Kazunori

2002-07-01

This report is intended to explain the outline of the research and development (R and D) in the FY 2001 on cost-benefit analysis of FR (Fast Reactor) cycle system concepts. The work was conducted as a part of the JNC's Feasibility Study on Commercialized Fast Reactor Cycle Systems (the F/S)'. In the FY 2001, the work conducted in the JNC was summed up as the followings: Conceptual study on cost-benefit analysis for FR cycle R and D. Refinement on the evaluation procedure and improvement over operation efficiency. Cost-benefit analysis of the reference FR cycle and sensitivity analysis with the revised system. Cost-benefit analyses of R and Ds for various FR cycle candidate concepts including FR cycle concepts studied in the F/S phase 1. The work made it possible to evaluate the cost effectiveness of various FR cycle systems efficiently. The cost-benefit analysis, which is often used for the policy evaluation, is considered to be applicable to FR cycle system concepts in the F/S. (author)

Environmentally based Cost-Benefit Analysis

International Nuclear Information System (INIS)

Magnell, M.

1993-11-01

The fundamentals of the basic elements of a new comprehensive economic assessment, MILA, developed in Sweden with inspiration from the Total Cost Assessment-model are presented. The core of the MILA approach is an expanded cost and benefit inventory. But MILA also includes a complementary addition of an internal waste stream analysis, a tool for evaluation of environmental conflicts in monetary terms, an extended time horizon and direct allocation of costs and revenues to products and processes. However, MILA does not ensure profitability for environmentally sound projects. Essentially, MILA is an approach of refining investment and profitability analysis of a project, investment or product. 109 refs., 38 figs

Use of external cost assessment and multi-criteria decision analysis for comparative evaluation of options for electricity supply

International Nuclear Information System (INIS)

Hirschberg, S.; Dones, R.; Gantner, U.

2001-01-01

The paper addresses external cost and multi-criteria analyses carried out for selected future electricity generating systems of interest under the Swiss conditions. The external cost estimates are based on an application of the 'impact pathway approach', enhanced by earlier experience from extensive Life Cycle Assessment (LCA). The estimated total costs, i.e. the sum of internal and external costs, may serve as a measure of economic and environmental efficiency of energy systems. The multi-criteria approach allows a more explicit consideration of the social dimension, which is highly important for the decision-making process. The applications of multi-criteria analyses illustrate the sensitivity of the results to the range of preferences expressed in the energy debate. Certain patterns in system ranking can be observed in spite of these sensitivities. Both total cost assessment and multi-criteria analysis are found to be useful, complementary instruments to support procedures for decision-making. (author)

Techniques for sensitivity analysis of SYVAC results

International Nuclear Information System (INIS)

Prust, J.O.

1985-05-01

Sensitivity analysis techniques may be required to examine the sensitivity of SYVAC model predictions to the input parameter values, the subjective probability distributions assigned to the input parameters and to the relationship between dose and the probability of fatal cancers plus serious hereditary disease in the first two generations of offspring of a member of the critical group. This report mainly considers techniques for determining the sensitivity of dose and risk to the variable input parameters. The performance of a sensitivity analysis technique may be improved by decomposing the model and data into subsets for analysis, making use of existing information on sensitivity and concentrating sampling in regions the parameter space that generates high doses or risks. A number of sensitivity analysis techniques are reviewed for their application to the SYVAC model including four techniques tested in an earlier study by CAP Scientific for the SYVAC project. This report recommends the development now of a method for evaluating the derivative of dose and parameter value and extending the Kruskal-Wallis technique to test for interactions between parameters. It is also recommended that the sensitivity of the output of each sub-model of SYVAC to input parameter values should be examined. (author)

Evaluation of pavement life cycle cost analysis: Review and analysis

Directory of Open Access Journals (Sweden)

Peyman Babashamsi

2016-07-01

Full Text Available The cost of road construction consists of design expenses, material extraction, construction equipment, maintenance and rehabilitation strategies, and operations over the entire service life. An economic analysis process known as Life-Cycle Cost Analysis (LCCA is used to evaluate the cost-efficiency of alternatives based on the Net Present Value (NPV concept. It is essential to evaluate the above-mentioned cost aspects in order to obtain optimum pavement life-cycle costs. However, pavement managers are often unable to consider each important element that may be required for performing future maintenance tasks. Over the last few decades, several approaches have been developed by agencies and institutions for pavement Life-Cycle Cost Analysis (LCCA. While the transportation community has increasingly been utilising LCCA as an essential practice, several organisations have even designed computer programs for their LCCA approaches in order to assist with the analysis. Current LCCA methods are analysed and LCCA software is introduced in this article. Subsequently, a list of economic indicators is provided along with their substantial components. Collecting previous literature will help highlight and study the weakest aspects so as to mitigate the shortcomings of existing LCCA methods and processes. LCCA research will become more robust if improvements are made, facilitating private industries and government agencies to accomplish their economic aims. Keywords: Life-Cycle Cost Analysis (LCCA, Pavement management, LCCA software, Net Present Value (NPV

Sensitivity analysis of a PWR pressurizer

International Nuclear Information System (INIS)

Bruel, Renata Nunes

1997-01-01

A sensitivity analysis relative to the parameters and modelling of the physical process in a PWR pressurizer has been performed. The sensitivity analysis was developed by implementing the key parameters and theoretical model lings which generated a comprehensive matrix of influences of each changes analysed. The major influences that have been observed were the flashing phenomenon and the steam condensation on the spray drops. The present analysis is also applicable to the several theoretical and experimental areas. (author)

Cost benefit analysis of two policy options for cannabis: status quo and legalisation.

Science.gov (United States)

Shanahan, Marian; Ritter, Alison

2014-01-01

To date there has been limited analysis of the economic costs and benefits associated with cannabis legalisation. This study redresses this gap. A cost benefit analysis of two cannabis policy options the status quo (where cannabis use is illegal) and a legalised-regulated option was conducted. A cost benefit analysis was used to value the costs and benefits of the two policies in monetary terms. Costs and benefits of each policy option were classified into five categories (direct intervention costs, costs or cost savings to other agencies, benefits or lost benefits to the individual or the family, other impacts on third parties, and adverse or spill over events). The results are expressed as a net social benefit (NSB). The mean NSB per annum from Monte Carlo simulations (with the 5 and 95 percentiles) for the status quo was $294.6 million AUD ($201.1 to $392.7 million) not substantially different from the $234.2 million AUD ($136.4 to $331.1 million) for the legalised-regulated model which excludes government revenue as a benefit. When government revenue is included, the NSB for legalised-regulated is higher than for status quo. Sensitivity analyses demonstrate the significant impact of educational attainment and wellbeing as drivers for the NSB result. Examining the percentiles around the two policy options, there appears to be no difference between the NSB for these two policy options. Economic analyses are essential for good public policy, providing information about the extent to which one policy is substantially economically favourable over another. In cannabis policy, for these two options this does not appear to be the case.

Cost benefit analysis of two policy options for cannabis: status quo and legalisation.

Directory of Open Access Journals (Sweden)

Marian Shanahan

Full Text Available AIMS: To date there has been limited analysis of the economic costs and benefits associated with cannabis legalisation. This study redresses this gap. A cost benefit analysis of two cannabis policy options the status quo (where cannabis use is illegal and a legalised-regulated option was conducted. METHOD: A cost benefit analysis was used to value the costs and benefits of the two policies in monetary terms. Costs and benefits of each policy option were classified into five categories (direct intervention costs, costs or cost savings to other agencies, benefits or lost benefits to the individual or the family, other impacts on third parties, and adverse or spill over events. The results are expressed as a net social benefit (NSB. FINDINGS: The mean NSB per annum from Monte Carlo simulations (with the 5 and 95 percentiles for the status quo was $294.6 million AUD ($201.1 to $392.7 million not substantially different from the $234.2 million AUD ($136.4 to $331.1 million for the legalised-regulated model which excludes government revenue as a benefit. When government revenue is included, the NSB for legalised-regulated is higher than for status quo. Sensitivity analyses demonstrate the significant impact of educational attainment and wellbeing as drivers for the NSB result. CONCLUSION: Examining the percentiles around the two policy options, there appears to be no difference between the NSB for these two policy options. Economic analyses are essential for good public policy, providing information about the extent to which one policy is substantially economically favourable over another. In cannabis policy, for these two options this does not appear to be the case.

National Variation in Urethroplasty Cost and Predictors of Extreme Cost: A Cost Analysis with Policy Implications

OpenAIRE

Harris, Catherine R.; Osterberg, E. Charles; Sanford, Thomas; Alwaal, Amjad; Gaither, Thomas W.; McAninch, Jack W.; McCulloch, Charles E.; Breyer, Benjamin N.

2016-01-01

To determine which factors are associated with higher costs of urethroplasty procedure and whether these factors have been increasing over time. Identification of determinants of extreme costs may help reduce cost while maintaining quality.We conducted a retrospective analysis using the 2001-2010 Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS). The HCUP-NIS captures hospital charges which we converted to cost using the HCUP cost-to-charge ratio. Log cost linear ...

Sensitivity Analysis of a Physiochemical Interaction Model ...

African Journals Online (AJOL)

In this analysis, we will study the sensitivity analysis due to a variation of the initial condition and experimental time. These results which we have not seen elsewhere are analysed and discussed quantitatively. Keywords: Passivation Rate, Sensitivity Analysis, ODE23, ODE45 J. Appl. Sci. Environ. Manage. June, 2012, Vol.

Cost-analysis of an oral health outreach program for preschool children in a low socioeconomic multicultural area in Sweden.

Science.gov (United States)

Wennhall, Inger; Norlund, Anders; Matsson, Lars; Twetman, Svante

2010-01-01

The aim was to calculate the total and the net costs per child included in a 3-year caries preventive program for preschool children and to make estimates of expected lowest and highest costs in a sensitivity analysis. The direct costs for prevention and dental care were applied retrospectively to a comprehensive oral health outreach project for preschool children conducted in a low-socioeconomic multi-cultural urban area. The outcome was compared with historical controls from the same area with conventional dental care. The cost per minute for the various dental professions was added to the cost of materials, rental facilities and equipment based on accounting data. The cost for fillings was extracted from a specified per diem list. Overhead costs were assumed to correspond to 50% of salaries and all costs were calculated as net present value per participating child in the program and expressed in Euro. The results revealed an estimated total cost of 310 Euro per included child (net present value) in the 3-year program. Half of the costs were attributed to the first year of the program and the costs of manpower constituted 45% of the total costs. When the total cost was reduced with the cost of conventional care and the revenue of avoided fillings, the net cost was estimated to 30 Euro. A sensitivity analysis displayed that a net gain could be possible with a maximal outcome of the program. In conclusion, the estimated net costs were displayed and available to those considering implementation of a similar population-based preventive program in areas where preschool children are at high caries risk.

Cost analysis of the development and implementation of a spatial decision support system for malaria elimination in Solomon Islands.

Science.gov (United States)

Marston, Luke; Kelly, Gerard C; Hale, Erick; Clements, Archie C A; Hodge, Andrew; Jimenez-Soto, Eliana

2014-08-18

The goal of malaria elimination faces numerous challenges. New tools are required to support the scale up of interventions and improve national malaria programme capacity to conduct detailed surveillance. This study investigates the cost factors influencing the development and implementation of a spatial decision support system (SDSS) for malaria elimination in the two elimination provinces of Isabel and Temotu, Solomon Islands. Financial and economic costs to develop and implement a SDSS were estimated using the Solomon Islands programme's financial records. Using an ingredients approach, verified by stakeholders and operational reports, total costs for each province were quantified. A budget impact sensitivity analysis was conducted to investigate the influence of variations in standard budgetary components on the costs and to identify potential cost savings. A total investment of US$ 96,046 (2012 constant dollars) was required to develop and implement the SDSS in two provinces (Temotu Province US$ 49,806 and Isabel Province US$ 46,240). The single largest expense category was for computerized equipment totalling approximately US$ 30,085. Geographical reconnaissance was the most expensive phase of development and implementation, accounting for approximately 62% of total costs. Sensitivity analysis identified different cost factors between the provinces. Reduced equipment costs would deliver a budget saving of approximately 10% in Isabel Province. Combined travel costs represented the greatest influence on the total budget in the more remote Temotu Province. This study provides the first cost analysis of an operational surveillance tool used specifically for malaria elimination in the South-West Pacific. It is demonstrated that the costs of such a decision support system are driven by specialized equipment and travel expenses. Such factors should be closely scrutinized in future programme budgets to ensure maximum efficiencies are gained and available resources

Eosinophilic esophagitis: dilate or medicate? A cost analysis model of the choice of initial therapy.

Science.gov (United States)

Kavitt, R T; Penson, D F; Vaezi, M F

2014-07-01

Eosinophilic esophagitis (EoE) is an increasingly recognized clinical entity. The optimal initial treatment strategy in adults with EoE remains controversial. The aim of this study was to employ a decision analysis model to determine the less costly option between the two most commonly employed treatment strategies in EoE. We constructed a model for an index case of a patient with biopsy-proven EoE who continues to be symptomatic despite proton-pump inhibitor therapy. The following treatment strategies were included: (i) swallowed fluticasone inhaler (followed by esophagogastroduodenoscopy [EGD] with dilation if ineffective); and (ii) EGD with dilation (followed by swallowed fluticasone inhaler if ineffective). The time horizon was 1 year. The model focused on cost analysis of initial treatment strategies. The perspective of the healthcare payer was used. Sensitivity analyses were performed to assess the robustness of the model. For every patient whose symptoms improved or resolved with the strategy of fluticasone first followed by EGD, if necessary, it cost an average of $1078. Similarly, it cost an average of $1171 per patient if EGD with dilation was employed first. Sensitivity analyses indicated that initial treatment with fluticasone was the less costly strategy to improve dysphagia symptoms as long as the effectiveness of fluticasone remains at or above 0.62. Swallowed fluticasone inhaler (followed by EGD with dilation if necessary) is the more economical initial strategy when compared with EGD with dilation first. © 2012 Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Lamb Production Costs: Analyses of Composition and Elasticities Analysis of Lamb Production Costs

Directory of Open Access Journals (Sweden)

C. Raineri

2015-08-01

Full Text Available Since lamb is a commodity, producers cannot control the price of the product they sell. Therefore, managing production costs is a necessity. We explored the study of elasticities as a tool for basing decision-making in sheep production, and aimed at investigating the composition and elasticities of lamb production costs, and their influence on the performance of the activity. A representative sheep production farm, designed in a panel meeting, was the base for calculation of lamb production cost. We then performed studies of: i costs composition, and ii cost elasticities for prices of inputs and for zootechnical indicators. Variable costs represented 64.15% of total cost, while 21.66% were represented by operational fixed costs, and 14.19% by the income of the factors. As for elasticities to input prices, the opportunity cost of land was the item to which production cost was more sensitive: a 1% increase in its price would cause a 0.2666% increase in lamb cost. Meanwhile, the impact of increasing any technical indicator was significantly higher than the impact of rising input prices. A 1% increase in weight at slaughter, for example, would reduce total cost in 0.91%. The greatest obstacle to economic viability of sheep production under the observed conditions is low technical efficiency. Increased production costs are more related to deficient zootechnical indexes than to high expenses.

A cost-benefit analysis of landfill mining and material recycling in China

International Nuclear Information System (INIS)

Zhou, Chuanbin; Gong, Zhe; Hu, Junsong; Cao, Aixin; Liang, Hanwen

2015-01-01

Highlights: • Assessing the economic feasibility of landfill mining. • We applied a cost-benefit analysis model for landfill mining. • Four material cycling and energy recovery scenarios were designed. • We used net present value to evaluate the cost-benefit efficiency. - Abstract: Landfill mining is an environmentally-friendly technology that combines the concepts of material recycling and sustainable waste management, and it has received a great deal of worldwide attention because of its significant environmental and economic potential in material recycling, energy recovery, land reclamation and pollution prevention. This work applied a cost-benefit analysis model for assessing the economic feasibility, which is important for promoting landfill mining. The model includes eight indicators of costs and nine indicators of benefits. Four landfill mining scenarios were designed and analyzed based on field data. The economic feasibility of landfill mining was then evaluated by the indicator of net present value (NPV). According to our case study of a typical old landfill mining project in China (Yingchun landfill), rental of excavation and hauling equipment, waste processing and material transportation were the top three costs of landfill mining, accounting for 88.2% of the total cost, and the average cost per unit of stored waste was 12.7 USD ton −1 . The top three benefits of landfill mining were electricity generation by incineration, land reclamation and recycling soil-like materials. The NPV analysis of the four different scenarios indicated that the Yingchun landfill mining project could obtain a net positive benefit varying from 1.92 million USD to 16.63 million USD. However, the NPV was sensitive to the mode of land reuse, the availability of energy recovery facilities and the possibility of obtaining financial support by avoiding post-closure care

A cost-benefit analysis of landfill mining and material recycling in China

Energy Technology Data Exchange (ETDEWEB)

Zhou, Chuanbin, E-mail: cbzhou@rcees.ac.cn; Gong, Zhe; Hu, Junsong; Cao, Aixin; Liang, Hanwen

2015-01-15

Highlights: • Assessing the economic feasibility of landfill mining. • We applied a cost-benefit analysis model for landfill mining. • Four material cycling and energy recovery scenarios were designed. • We used net present value to evaluate the cost-benefit efficiency. - Abstract: Landfill mining is an environmentally-friendly technology that combines the concepts of material recycling and sustainable waste management, and it has received a great deal of worldwide attention because of its significant environmental and economic potential in material recycling, energy recovery, land reclamation and pollution prevention. This work applied a cost-benefit analysis model for assessing the economic feasibility, which is important for promoting landfill mining. The model includes eight indicators of costs and nine indicators of benefits. Four landfill mining scenarios were designed and analyzed based on field data. The economic feasibility of landfill mining was then evaluated by the indicator of net present value (NPV). According to our case study of a typical old landfill mining project in China (Yingchun landfill), rental of excavation and hauling equipment, waste processing and material transportation were the top three costs of landfill mining, accounting for 88.2% of the total cost, and the average cost per unit of stored waste was 12.7 USD ton{sup −1}. The top three benefits of landfill mining were electricity generation by incineration, land reclamation and recycling soil-like materials. The NPV analysis of the four different scenarios indicated that the Yingchun landfill mining project could obtain a net positive benefit varying from 1.92 million USD to 16.63 million USD. However, the NPV was sensitive to the mode of land reuse, the availability of energy recovery facilities and the possibility of obtaining financial support by avoiding post-closure care.

DVT surveillance program in the ICU: analysis of cost-effectiveness.

Directory of Open Access Journals (Sweden)

Ajai K Malhotra

Full Text Available BACKGROUND: Venous Thrombo-embolism (VTE--Deep venous thrombosis (DVT and/or pulmonary embolism (PE--in traumatized patients causes significant morbidity and mortality. The current study evaluates the effectiveness of DVT surveillance in reducing PE, and performs a cost-effectiveness analysis. METHODS: All traumatized patients admitted to the adult ICU underwent twice weekly DVT surveillance by bilateral lower extremity venous Duplex examination (48-month surveillance period--SP. The rates of DVT and PE were recorded and compared to the rates observed in the 36-month pre-surveillance period (PSP. All patients in both periods received mechanical and pharmacologic prophylaxis unless contraindicated. Total costs--diagnostic, therapeutic and surveillance--for both periods were recorded and the incremental cost for each Quality Adjusted Life Year (QALY gained was calculated. RESULTS: 4234 patients were eligible (PSP--1422 and SP--2812. Rate of DVT in SP (2.8% was significantly higher than in PSP (1.3% - p<0.05, and rate of PE in SP (0.7% was significantly lower than that in PSP (1.5% - p<0.05. Logistic regression demonstrated that surveillance was an independent predictor of increased DVT detection (OR: 2.53 - CI: 1.462-4.378 and decreased PE incidence (OR: 0.487 - CI: 0.262-0.904. The incremental cost was $509,091/life saved in the base case, translating to $29,102/QALY gained. A sensitivity analysis over four of the parameters used in the model indicated that the incremental cost ranged from $18,661 to $48,821/QALY gained. CONCLUSIONS: Surveillance of traumatized ICU patients increases DVT detection and reduces PE incidence. Costs in terms of QALY gained compares favorably with other interventions accepted by society.

24 CFR 84.45 - Cost and price analysis.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Cost and price analysis. 84.45....45 Cost and price analysis. Some form of cost or price analysis shall be made and documented in the procurement files in connection with every procurement action. Price analysis may be accomplished in various...

Cost Analysis In A Multi-Mission Operations Environment

Science.gov (United States)

Newhouse, M.; Felton, L.; Bornas, N.; Botts, D.; Roth, K.; Ijames, G.; Montgomery, P.

2014-01-01

Spacecraft control centers have evolved from dedicated, single-mission or single missiontype support to multi-mission, service-oriented support for operating a variety of mission types. At the same time, available money for projects is shrinking and competition for new missions is increasing. These factors drive the need for an accurate and flexible model to support estimating service costs for new or extended missions; the cost model in turn drives the need for an accurate and efficient approach to service cost analysis. The National Aeronautics and Space Administration (NASA) Huntsville Operations Support Center (HOSC) at Marshall Space Flight Center (MSFC) provides operations services to a variety of customers around the world. HOSC customers range from launch vehicle test flights; to International Space Station (ISS) payloads; to small, short duration missions; and has included long duration flagship missions. The HOSC recently completed a detailed analysis of service costs as part of the development of a complete service cost model. The cost analysis process required the team to address a number of issues. One of the primary issues involves the difficulty of reverse engineering individual mission costs in a highly efficient multimission environment, along with a related issue of the value of detailed metrics or data to the cost model versus the cost of obtaining accurate data. Another concern is the difficulty of balancing costs between missions of different types and size and extrapolating costs to different mission types. The cost analysis also had to address issues relating to providing shared, cloud-like services in a government environment, and then assigning an uncertainty or risk factor to cost estimates that are based on current technology, but will be executed using future technology. Finally the cost analysis needed to consider how to validate the resulting cost models taking into account the non-homogeneous nature of the available cost data and the

Neurobehavioral deficits, diseases, and associated costs of exposure to endocrine-disrupting chemicals in the European Union.

Science.gov (United States)

Bellanger, Martine; Demeneix, Barbara; Grandjean, Philippe; Zoeller, R Thomas; Trasande, Leonardo

2015-04-01

Epidemiological studies and animal models demonstrate that endocrine-disrupting chemicals (EDCs) contribute to cognitive deficits and neurodevelopmental disabilities. The objective was to estimate neurodevelopmental disability and associated costs that can be reasonably attributed to EDC exposure in the European Union. An expert panel applied a weight-of-evidence characterization adapted from the Intergovernmental Panel on Climate Change. Exposure-response relationships and reference levels were evaluated for relevant EDCs, and biomarker data were organized from peer-reviewed studies to represent European exposure and approximate burden of disease. Cost estimation as of 2010 utilized lifetime economic productivity estimates, lifetime cost estimates for autism spectrum disorder, and annual costs for attention-deficit hyperactivity disorder. Setting, Patients and Participants, and Intervention: Cost estimation was carried out from a societal perspective, ie, including direct costs (eg, treatment costs) and indirect costs such as productivity loss. The panel identified a 70-100% probability that polybrominated diphenyl ether and organophosphate exposures contribute to IQ loss in the European population. Polybrominated diphenyl ether exposures were associated with 873,000 (sensitivity analysis, 148,000 to 2.02 million) lost IQ points and 3290 (sensitivity analysis, 3290 to 8080) cases of intellectual disability, at costs of €9.59 billion (sensitivity analysis, €1.58 billion to €22.4 billion). Organophosphate exposures were associated with 13.0 million (sensitivity analysis, 4.24 million to 17.1 million) lost IQ points and 59 300 (sensitivity analysis, 16,500 to 84,400) cases of intellectual disability, at costs of €146 billion (sensitivity analysis, €46.8 billion to €194 billion). Autism spectrum disorder causation by multiple EDCs was assigned a 20-39% probability, with 316 (sensitivity analysis, 126-631) attributable cases at a cost of €199 million

43 CFR 12.945 - Cost and price analysis.

Science.gov (United States)

2010-10-01

... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Cost and price analysis. 12.945 Section 12... Requirements § 12.945 Cost and price analysis. Some form of cost or price analysis shall be made and documented in the procurement files in connection with every procurement action. Price analysis may be...

22 CFR 145.45 - Cost and price analysis.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Cost and price analysis. 145.45 Section 145.45....45 Cost and price analysis. Some form of cost or price analysis shall be made and documented in the procurement files in connection with every procurement action. Price analysis may be accomplished in various...

Costs and cost-effectiveness of training traditional birth attendants to reduce neonatal mortality in the Lufwanyama Neonatal Survival study (LUNESP).

Science.gov (United States)

Sabin, Lora L; Knapp, Anna B; MacLeod, William B; Phiri-Mazala, Grace; Kasimba, Joshua; Hamer, Davidson H; Gill, Christopher J

2012-01-01

The Lufwanyama Neonatal Survival Project ("LUNESP") was a cluster randomized, controlled trial that showed that training traditional birth attendants (TBAs) to perform interventions targeting birth asphyxia, hypothermia, and neonatal sepsis reduced all-cause neonatal mortality by 45%. This companion analysis was undertaken to analyze intervention costs and cost-effectiveness, and factors that might improve cost-effectiveness. We calculated LUNESP's financial and economic costs and the economic cost of implementation for a forecasted ten-year program (2011-2020). In each case, we calculated the incremental cost per death avoided and disability-adjusted life years (DALYs) averted in real 2011 US dollars. The forecasted 10-year program analysis included a base case as well as 'conservative' and 'optimistic' scenarios. Uncertainty was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. The estimated financial and economic costs of LUNESP were $118,574 and $127,756, respectively, or $49,469 and $53,550 per year. Fixed costs accounted for nearly 90% of total costs. For the 10-year program, discounted total and annual program costs were $256,455 and $26,834 respectively; for the base case, optimistic, and conservative scenarios, the estimated cost per death avoided was $1,866, $591, and $3,024, and cost per DALY averted was $74, $24, and $120, respectively. Outcomes were robust to variations in local costs, but sensitive to variations in intervention effect size, number of births attended by TBAs, and the extent of foreign consultants' participation. Based on established guidelines, the strategy of using trained TBAs to reduce neonatal mortality was 'highly cost effective'. We strongly recommend consideration of this approach for other remote rural populations with limited access to health care.

QUANTIFYING BENEFITS FOR COST-BENEFIT ANALYSIS

OpenAIRE

Attila GYORGY; Nicoleta VINTILA; Florian GAMAN