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PubMed2003

Environmental regulation through trade: the case of shrimp.

The implications of a potential ban on shrimp imports by the US from countries that do not utilize the Turtle Excluder Device on commercial shrimp nets is explored in this paper. A Linear Expenditure System (LES) was used to determine the own-price elasticities of demand for shrimp imports. The system of estimated equations was then solved for quantity levels under assumptions made about the trade restrictions, resulting in a set of prices for those import levels. These estimated prices were then used to estimate the compensating variation impact of the trade restrictions. Findings suggest that the environmental regulation would have a negative impact on US consumers, but the magnitude of that effect depends on assumptions made regarding the distribution of US imports after the trade restriction is imposed.

Animals↗
PubMed2003

Environmental impacts of modern agricultural technology diffusion in Bangladesh: an analysis of farmers' perceptions and their determinants.

Farmers' perception of the environmental impacts of modern agricultural technology diffusion and factors determining such awareness were examined using survey data from 21 villages in three agro-ecological regions of Bangladesh. Results reveal that farmers are well aware of the adverse environmental impacts of modern agricultural technology, although their awareness remains confined within visible impacts such as soil fertility, fish catches, and health effects. Their perception of intangible impacts such as, toxicity in water and soils is weak. Level and duration of modern agricultural technology adoption directly influence awareness of its adverse effects. Education and extension contacts also play an important role in raising awareness. Awareness is higher among farmers in developed regions, fertile locations and those with access to off-farm income sources. Promotion of education and strengthening extension services will boost farmers' environmental awareness. Infrastructure development and measures to replenish depleting soil fertility will also play a positive role in raising awareness.

Agriculture↗
PubMed2003

Aggregating the benefits of environmental improvements: distance-decay functions for use and non-use values.

One of the main problems in using environmental cost-benefit analysis is deciding on the relevant population: whose benefits should we count? This is important since aggregate benefits depend on both per-person benefit and the number of beneficiaries. Yet this latter term is often hard to evaluate. Distance-decay functions are one way of addressing this problem. In this paper, we present estimates of distance-decay functions for a particular environmental improvement, namely a reduction in low flow problems on the River Mimram in Southern England. We do this both for users and non-users, in the context of a contingent valuation study of the benefits of improving low flow conditions. We test whether distance-decay effects for mean Willingness to Pay are stronger for a single environmental good (the River Mimram, in this case) than for a more inclusive set (here, all rivers in Thames region which suffer from low flow problems). Finally, we explore the impact on part-whole bias, in terms of the relationship between WTP for an individual site and WTP for a more inclusive group of sites, of allowing for distance-decay effects.

Attitude↗
PubMed1998

Radiobiologically based assessments of the net costs of fractionated focal radiotherapy.

PURPOSE: To assess the potential changes in the net costs of focal radiotherapy techniques at differing doses per fraction and interfraction intervals. METHODS: Linear quadratic radiobiological modeling is used with appropriate variations in the radiosensitivity and tumor cell proliferation parameters. The notional cost of treatment is calculated from the number of fractions, cost per fraction and the cost of treatment failure, which is itself related to (1-TCP) where TCP is the tumor cure probability. Additional Monte Carlo calculations from ranges of radiobiological parameters have been used to simulate the cost of treatment of tumor populations. RESULTS: The optimum dose per fraction (and optimum overall cost) for conventional (nonfocal) radiotherapy is generally at low doses of around 2 Gy per fraction. The use of hyperfractionated and accelerated radiotherapy in addition to focal radiotherapy techniques appear to be indicated for more radioresistant tumors and if tumor proliferation is extremely rapid, but the need for treatment acceleration is much reduced where effective focal techniques are used. CONCLUSIONS: Radiobiological and economic modeling can be used to guide clinical choices of dose fractionation techniques providing the key radiobiological parameters are known or if the ranges of likely parameters in a tumor population are known. Focal radiotherapy, by the introduction of changes in the physical dose distribution, produces an upward shift in the optimum dose per fraction and a reduced dependency on overall treatment time.

Cell Division↗
PubMed2001

The impact of statistical adjustment on economic profiles of interventional cardiologists.

OBJECTIVES: The objective of this study was to identify preprocedure patient factors associated with percutaneous intervention costs and to examine the impact of these patient factors on economic profiles of interventional cardiologists. BACKGROUND: There is increasing demand for information about comparative resource use patterns of interventional cardiologists. Economic provider profiles, however, often fail to account for patient characteristics. METHODS: Data were obtained from Duke Medical Center cost and clinical information systems for 1,949 procedures performed by 13 providers between July 1, 1997, and December 31, 1998. Patient factors that influenced cost were identified using multiple regression analysis. After assessing interprovider variation in unadjusted cost, mixed linear models were used to examine how much cost variability was associated with the provider when patient characteristics were taken into account. RESULTS: Total hospital costs averaged $15,643 (median, $13,809), $6,515 of which represented catheterization laboratory costs. Disease severity, acuity, comorbid illness and lesion type influenced total costs (R(2) = 38%), whereas catheterization costs were affected by lesion type and acuity (R(2) = 32%). Patient characteristics varied significantly among providers. Unadjusted total costs were weakly associated with provider, and this association disappeared after accounting for patient factors. The provider influence on catheterization costs persisted after adjusting for patient characteristics. Furthermore, the pattern of variation changed: the adjusted analysis identified three new outliers, and two providers lost their outlier status. Only one provider was consistently identified as an outlier in the unadjusted and adjusted analyses. CONCLUSIONS: Economic profiles of interventional cardiologists may be misleading if they do not adequately adjust for patient characteristics before procedure.

Academic Medical Centers↗
PubMed2001

Simulated effect of tobacco tax variation on Latino health in California.

BACKGROUND: Over one fourth of the California population was Latino in 1999, and by 2015 Latinos are expected to be the single largest ethnic group in California. Patterns of smoking and nicotine dependence among Latino smokers may be quite different from those of smokers in other ethnic groups. In addition, Latino smokers may be more sensitive to cigarette prices. Therefore, the effect of an increase in cigarette excise taxes on Latino smoking prevalence may be quite large, and consequently the impact on Latino health may be proportionately greater than on population health in general. METHODS: We simulated changes in Latino smoking, morbidity, mortality, and quality-adjusted life years (QALYs) that would result from a range of actual and proposed cigarette excise-tax increases using a range of cigarette price-elasticity estimates specific to Latino smokers. Monte Carlo simulation was used to generate confidence intervals. RESULTS: Assuming a Latino price elasticity of demand for cigarettes of -1.0, reductions in Latino smoking resulting from an additional $0.50/pack tax would produce nearly 3000 Latino QALYs in California in 1999. Greater benefits would accrue each year, until a steady state relative to population size is reached 75 years after the program is initiated. CONCLUSIONS: If Latino smokers are more responsive to changes in cigarette prices than other smokers, Latino smokers also stand to gain a disproportionate share of the health benefit from an excise tax increase.

California↗
PubMed2000

Hospital and unit cost allocation methods.

The quest for an efficient healthcare system has resulted in the publication of many assessments relating to health facilities. Some use a methodological approach that, at first glance, appears questionable in terms of allocation of overhead or support costs among the facilities' centres of activity. The objective of this article is to verify, using hospital utilization data, whether the choice of an allocation method significantly affects the unit cost of such resources. The results obtained from our sample suggest that no statistically significant relationship exists between the methods used and the unit costs produced.

Accounting↗
PubMed1992

Alberta's Acute Care Funding Project.

Alberta initiated the Acute Care Funding Project (ACFP) in 1988, a new hospital funding system that institutes case mix budgeting adjustments to the global budget so that hospitals can be treated more equitably. The initiative is a significant departure in principle from the former method of funding. The ACFP is summarized and critiqued, and focuses on the inpatient side of the picture. The various elements of the project are discussed, such as the hospital performance index, the hospital performance measure, the Refined Diagnostic Related Group, case weights, typical and outlier cases, and the costing mechanisms. Since its implementation, the ACFP has undergone substantial changes; these are discussed, as well as some of the problems that still need to be addressed. Overall, the system offers incentives to reduce length of stay and to increase the efficiency with which inpatient care is provided.

Alberta↗
PubMed1991

Ontario's hospital transitional funding initiative: an overview and assessment.

In 1989, the hospital transitional funding initiative, which incorporates case mix measurement into the hospital funding process, was started in Ontario. This initiative is the beginning of a new, more objective basis for determining hospital funding. In its initial stages, incremental growth and interhospital equity adjustments are made to the global budgets. In this paper, we describe the launching of this initiative and the funding formulas that emerged from its first phase. The issue of incentive effects is then discussed and, as this is an evolving or "transitional" undertaking, we comment on several economic issues arising as a result of this new venture.

Accounting↗
PubMed1991

Principles for funding on a case mix basis: construction of case weights (RIWs).

The construct of Resource Intensity Weights (RIWs) contains implicit financial incentives if they are used for hospital funding purposes. This paper compares the RIW (funding) credit to the expected average per diem cost for each of the new subcategories (typicals, deaths, transfers, signouts and outliers) of Case Mix Groups (CMGs). RIW construction, and inherent incentives for a hospital to reduce costs or length of stay (LOS), differ significantly for each subcategory. At some point or points in a patient's LOS, when RIW credit equals case cost, RIWs are incentive neutral. However, it can also be demonstrated that RIW credit is not generally congruent with average costs on each day of a patient's stay. Financial incentives (both positive and negative) arise when RIW credit and costs differ. Only by being fully aware of these differences can hospitals determine how to respond to the introduction of case mix funding to maintain financial viability. Funding agencies, too, need to appreciate the sometimes subtle policy implications that come with the adoption of RIWs for funding purposes.

Accounting↗
PubMed1992

Hospital reimbursement in Alberta: outcomes management is on the way.

The Alberta government has initiated a process to alter fundamentally the way it pays hospitals. As with most provinces, Alberta has been paying hospitals for what they spend. The new Alberta model will initially pay hospitals for what they do and ultimately will pay hospitals for what they ought to do; that is, for the outcomes that should be achieved. This article describes the initial step of what is expected to be a lengthy journey. The principles underlying the model are: it should be a prospective case-based system; there should be performance linkages between types of hospitals; severity should be incorporated into the model; and cost or cost proxies should be used where possible in weight development and clinical concerns, both nursing and medical, should be addressed. For the past two years funding adjustments have been made on the basis of the calculation of a Hospital Performance Index (HPI). The HPI is the average predicted cost per case divided by the unweighted average actual cost per case. The HPI is intended as an interim measure only. Ultimately, the system will evolve into a true prospective case-based system with volume controlled via role statements and linked to clinical outcomes.

Alberta↗
PubMed1996

Application of a classical model of competitive business strategy to orthodontic practice.

This study explored how market forces might affect the business aspects of orthodontic practices; in particular, profitability. The forces identified were (1) intensity of rivalry, (2) threat of new entrants, and (3) bargaining power of buyers and suppliers. A mail survey instrument was used to collect the data. Results showed that more than half the surveyed practices show an increase in new case starts despite weak economic conditions. Although satellite offices and marketing increase the overhead, they do not add to net profit. New entrants are a threat to existing practices, as are the substitute discretionary spending by the consumer. Interestingly, while some orthodontic practices have joined the managed care programs, a majority of them realize neither increased patient load nor profit. Our data seem to indicate that orthodontic practices have not been successful in "cost containment" with their marketing, number of employees, computerization or inventory. Collectively, the results of this study suggest that success in an orthodontic office is primarily dependent on the practitioner's personality traits, rather than rigidly applied business principles.

Attitude of Health Personnel↗
PubMed2003

Measures of importance for economic analysis based on decision modeling.

In probabilistic economic analysis, the uncertainty concerning input parameters is quantified, and determines the level of uncertainty over the optimal decision. Researchers from a wide range of disciplines employ mathematical models to simulate complex processes. Common through many such disciplines is the conduct of importance analysis to determine those input parameters that contribute most to the uncertainty over the optimal decision based on the results of the analysis. In this study, we compare a range of potential importance measures to see how they compare with methods used in economic analysis. Techniques were classified as variance/correlation, information, probability, entropy, or elasticity-based measures. A selection of the most commonly used measures were applied to an economic model of treatment for patients with Parkinson's disease. Techniques were evaluated in terms of their ranking of variables, complexity, and interpretation.

Cost-Benefit Analysis↗
PubMed1999

Comparison of the cost-effectiveness of milnacipran (a SNRI) with TCAs and SSRIs: a modeling approach.

A simulation model based on the theory of clinical decision analysis was used to compare outcomes and costs when treating patients with major depressive episodes using either a selective serotonin re-uptake inhibitor (SSRI) or a tricyclic antidepressant (TCA), in comparison with milnacipran (a serotonin), and a norepinephrine re-uptake inhibitor (SNRI). The clinical data used were taken from published meta-analyses. This analysis supports: (1) a comparable efficacy of milnacipran and TCA with a better tolerance; and, (2) an advantage of milnacipran over SSRI for efficacy with a comparable tolerance. Based on these findings, a decision tree was constructed with the assistance of a panel of psychiatrists in order to provide a model of usual clinical practice. Estimates not available from clinical studies were obtained either from literature analysis or from the panel. Economic appraisal was performed according to the viewpoint of the French national sickness fund (sécurité sociale), and expenditure assessment was limited to direct costs (hospitalizations, antidepressant medications, visits, and laboratory tests). The results suggest that milnacipran is a cost-effective alternative: the expected cost of treatment per depressive episode is lower than either a French representative panel of TCAs (a saving of 288 FF), or SSRIs (a savings of 961 FF). The expected length of clinical remission is slightly higher than comparators. The robustness of these findings was supported by sensitivity analyses.

Adrenergic Antagonists↗
PubMed2001

Canada's Population Health Model (POHEM): a tool for performing economic evaluations of cancer control interventions.

This paper describes the Population Health Model (POHEM) developed by Statistics Canada and shows its usefulness in the evaluation of cancer control interventions and policy decision-making. Models of the costs of diagnosis and treatment of lung and breast cancer were developed and incorporated into POHEM. Then, POHEM was used to evaluate the economic impact of chemotherapy for advanced non-small cell lung cancer; reduced length of hospital stay following breast cancer surgery; and the provision of preventive tamoxifen to women at high risk of breast cancer. A lung cancer chemotherapy treatment decision framework was developed to rank order currently available chemotherapy regimens according to relative cost-effectiveness and cost-utility. Reducing post-surgical breast cancer hospitalisation with optimal home care support could produce major healthcare savings. However, the provision of preventive tamoxifen was estimated to have no population health benefit. This paper demonstrates that POHEM is an effective tool for performing economic evaluations of cancer control interventions and to inform healthcare policy decisions.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

The costs of head and neck oncology: primary tumours, recurrent tumours and long-term follow-up.

We retrospectively calculated the costs of head and neck oncology for reimbursement purposes. This analysis was based on 854 head and neck cancer patients treated between 1994 and 1996 in two major Dutch university hospitals. To anticipate future care costs, costs of required improvements in the quality of care were added. Costs of diagnosis, treatment and 2 years of follow-up of patients with a primary tumour were (euro) 21 858. For patients with a recurrent tumour, this amount was (euro) 27 629. The costs of 10 years of follow-up were (euro) 423 after discounting and correction for survival. In total, average costs per new patient were (euro) 31 829, which covered discounted costs of treating the primary tumour, costs of treating recurrent tumours in 40% of all patients and the costs of 10 years of follow-up. Costs of improving the quality of care were estimated to be (euro) 1598 per new patient.

Continuity of Patient Care↗
PubMed2001

Efficient use of animal manure on cropland--economic analysis.

Manure contains all the macro- and microelements needed for plant growth; however, it represents one of the most underutilized resources in the US. The major problem with the use of manure on cropland is the direct effect of its composition on application cost. This cost is a function of the mineralization process of organic matter. The mineralization process is influenced by the properties of the manure, properties of the soil, moisture, and temperature. This study evaluates the simultaneous effect of these variables on the optimal use of manure on cropland. The results show that the properties of manure and soil significantly affect the mineralization of organic nitrogen and thus the optimal quantity of manure required to satisfy the nutrient requirement of crops in a given rotation system. Manure application costs range from a low of 18% of the cost of commercial fertilizer for chicken manure applied to one type of soil, to a high of 125% of the cost of commercial fertilizer for cow manure applied to another type of soil. The maximum distance to transfer manure to the field, that will equate its application cost to the cost of commercial fertilizer, ranges from a high of 35 km (22 miles) for chicken manure applied to one type of soil, to a low of 1 km (0.62 miles) for cow manure applied to another type of soil. For rotation system 2, manure application costs range from a low of 37% of the cost of commercial fertilizer for chicken manure applied to one type of soil, to a high of 136% of the cost of commercial fertilizer for cow manure applied to another type of soil. The maximum distance to transfer manure to the field, that will equate its cost to the cost of commercial fertilizer, ranges from a high of 20 km (12.5 miles) for chicken manure applied to one type of soil, to a low of 0 km (0 miles) for cow manure applied to another type of soil.

Agriculture↗