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Student evaluation: a performance indicator of quality in nurse education.

This study, which forms part of a doctoral thesis, is derived from the increasing demand for economic models of nurse education as a process within a wider economic agenda which converts inputs (e.g. training costs) into outputs (e.g. registered nurses). In such a climate the pursuance and determination of quality in nurse education should be of fundamental concern to the nursing profession. The development of models for evaluation and measurement of quality must take due cognisance of the stakeholders' interests and concerns, and student nurses, as the consumers of nurse education, must be regarded as major stakeholders. This paper describes the use of the course experience questionnaire, an instrument designed to investigate the students' perspective on teaching and learning. The study incorporates a comparative analysis between Project 2000 students in Northern Ireland and students in the apprenticeship programme in the Republic of Ireland, from general, psychiatric, sick children's and mental handicap nursing. This comparative analysis does provide the nursing profession with a level of feedback on which to make decisions in the interest of quality. Nurse teachers should examine potential reasons why their programmes are poorly or highly rated and the actions that may be required to remedy imperfections on the one hand and the actions that may be taken to promote excellence on the other. As nurse education continues to forge links with universities, nurse teachers, by adopting student evaluation as a performance indicator, can maximize an essential element in the web of public accountability.

Adolescent↗

Modelling the costs of fox predation and preventive measures on sheep farms in Britain.

Economic analysis is a useful tool to aid decisions on what to do about wildlife impacts, such as those of vertebrate predators on livestock farmers. The case-study of lamb predation by foxes in Britain is used to develop a theoretical economic model, with the aim of determining a financially optimal solution to minimise the total costs of livestock predation at the farm-level. Total costs include output losses and expenditure on preventive and control measures, in this case indoor housing and lethal fox control. The model is tested empirically with data from a questionnaire survey of sheep farmers and field data on fox population densities in Britain. Regression analyses are used to determine the relationships between lamb losses and expenditure on indoor housing, fox population density and other non-management characteristics. The effect of fox abundance on the cost of fox control is also assessed. Marginal analysis is used to determine the total cost-minimising solution from the farmer's point-of-view, in terms of how many ewes should be housed indoors and for how long, as well as how many foxes should be killed in addition to any lethal control already carried out. Optimal solutions vary according to farm characteristics, including flock size and the regional location of farms. In all cases, to minimise the costs of predation, as many ewes as possible should be housed. However, it is not worthwhile housing them for more than a day after lambing. Efficient fox predation management does not necessarily mean that lamb losses should be reduced to zero, and additional fox control is not worthwhile on the majority of farms. The analysis provides a framework for future evaluations of wildlife impacts and cost-effective management of these problems.

Animal Husbandry↗

The worm has turned--microbial virulence modeled in Caenorhabditis elegans.

The nematode Caenorhabditis elegans is emerging as a facile and economical model host for the study of evolutionarily conserved mechanisms of microbial pathogenesis and innate immunity. A rapidly growing number of human and animal microbial pathogens have been shown to injure and kill nematodes. In many cases, microbial genes known to be important for full virulence in mammalian models have been shown to be similarly required for maximum pathogenicity in nematodes. C. elegans has been used in mutation-based screening systems to identify novel virulence-related microbial genes and immune-related host genes, many of which have been validated in mammalian models of disease. C. elegans-based pathogenesis systems hold the potential to simultaneously explore the molecular genetic determinants of both pathogen virulence and host defense.

Animals↗

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↗

Stakeholder position paper: economist's perspectives on antibiotic use in animals.

Economics seeks to understand and explain the allocation of resources within society and to suggest appropriate policy to achieve goals such as optimal efficiency. Relating antimicrobial use and antibiotic resistance is a complex task and requires very clear and careful analyses of many relationships. To address these relationships, antibiotic use data must be linked with other basic data. Ideally, a complex relational database needs to be developed. These must include data on: antimicrobial usage, farm-level animal productivity, basic disease, basic farm management, consumer response, and antimicrobial resistance at multiple levels (farm, during process, on a variety of both animal, vegetable and grain-derived food products, from humans, from other animal species, and from the environment) among other data. Such a complex relational database can help with the attribution and risk assessment process. Also these linked data are needed in order to develop the economic production models and other economic models, as well as control for confounding so that there is both adequate and appropriate statistical control. Antimicrobial usage data may become economically important for reasons unrelated to animal productivity and animal health. With expanding global trade of animals and animal products, there have been changes in restrictions and regulations associated with the movement of products. Future trade opportunities may be linked to antimicrobial usage. The European Union banned the use of antimicrobials for growth-promoting purposes based on perceived risk and on public opinion. Monitoring antimicrobial use, disease occurrence, and resistance patterns following changes in usage that are a result of either policy changes or response to new information will help in the understanding of the complex relationships in microbial and disease ecology. There is a lot of evidence substantiating the productivity and profitability gains to producers from the use of antimicrobials. There is also evidence for the potential gains to consumers, both from an economic perspective as well as from a health perspective. Economists can help identify the implications of these relationships both at a micro- and macro-economic level; both relative to producer and to consumer welfare. We are at a pivotal time in history with sufficient analytical expertise and tools to address this complex issue from a scientific perspective. Linking various agencies so there can be coordination of data collection and data sharing is needed to successfully address this topic.

Animal Husbandry↗

Systematic assessment of decision models in Parkinson's disease.

OBJECTIVE: To give an insight into the structural and methodological approaches used in published decision-analytic models evaluating interventions in Parkinson's disease (PD) and to derive recommendations for future comprehensive PD decision models. METHODS: A systematic literature review was performed to identify studies that evaluated PD interventions using mathematical decision models. Using a standardized assessment form, information on the study design, methodological framework, and data sources was extracted from each publication and systematically reported. Strengths and limitations were assessed. RESULTS: We identified eight studies that used mathematical models to evaluate different pharmaceutical (n=7) and surgical (n=1) treatment options in PD. All models included economic evaluations. Modeling approaches comprised mathematical equations, decision trees, and Markov models with a time horizon ranging from 5 years to lifetime. All based progression on the evolution of clinical surrogate endpoints. Treatment effects were either modeled via reduction of symptomatic progression and/or initial symptomatic improvement or via reduction of adverse effect rates. No model is currently available that encompasses both the underlying biologic disease progression and the spectrum of all relevant complications and also links them to patient preferences and economic outcomes. CONCLUSIONS: Models have been successfully applied to evaluate PD treatments. However, currently available models have substantial limitations. We recommend that a comprehensive, generic, and flexible decision model for PD that can be applied to different treatment strategies should consider a large spectrum of clinically relevant outcomes and complications of the disease during a sufficiently long time horizon, include PD-specific mortality, systematically evaluate uncertainty including heterogeneity effects, and should be validated by independent data or other models. Approaches to model treatment effects included reduction of symptomatic progression, initial symptomatic improvement, or reduction of adverse effects. We believe that structural bias could be avoided if underlying disease progression and treatment effects on symptoms are modeled separately.

Cost-Benefit Analysis↗

Life cycle analysis of Municipal Solid Waste management possibilities in Asturias, Spain.

Directive 1994/62 concerning packaging and packaging waste and Directive 1999/31 related to waste disposal will substantially modify the management and treatment of Municipal Solid Waste (MSW) in Europe. In this study, a life cycle analysis has been carried out of the different possibilities of managing Municipal Solid Waste in Asturias. The "Integrated Waste Management" (IWM-1) model was employed, analysing the different alternatives for collection and treatment of MSW. This model predicts overall environmental burdens of MSW management systems and includes a parallel economical model. The sources of costs in the different systems of collection and treatment of MSW were considered in the economical analysis, as well as the sources of resource gathering that may be obtained via the sale of recovered materials. What emerges from this study is the soundness of management strategies based on biological treatment technologies in comparison with thermal treatments, together with the need to increase the level of collection at source.

Costs and Cost Analysis↗

Economic impacts of regional ozone standards on agricultural crops.

Implementing ozone (O3) standards on regional air sheds on the basis of crop losses requires more precise analysis than statewide or even national assessments. An economic model that measures crop losses by air basins in California is described. The ability of the model to respond to subtle regional changes in O3 standards is tested. Substantial differences in economic benefits between different standards and regions result from the model simulations. Regional standards are shown to capture a large proportion of the benefits at a lower cost.

Journal Article↗

Prostaglandin analogues for the treatment of glaucoma and ocular hypertension: a systematic review of economic evidence.

We conducted a systematic review of economic studies of prostaglandin analogues for the treatment of glaucoma to assess the scope of current cost-effectiveness evidence and its relevance to decision-makers. The literature search retrieved 102 studies published before July 2005; after additional hand searching of conference proceedings, 13 full-text articles and 13 abstracts met the inclusion criteria. The reviewers extracted the key characteristics of each of the economic evaluations, and all studies received a grade in five categories to summarise the quality of the study: methodology, transparency, sensitivity, relevance and overall score. The current economic literature is predominantly focused on identifying the short-term direct cost of glaucoma treatment, particularly the precise quantification of glaucoma drug costs. Using the European and US treatment guidelines as a benchmark, it is evident that the current body of literature does not satisfy the needs of decision-makers, although certain studies provide some valuable information, which is a step towards reaching this goal. The main methodological issue in the economic models is an absence of a clinically relevant long-term effectiveness measure, or where this measure is produced, there is a lack of transparency and validation of the methods used. More attention needs to be given to modelling the consequences of treatment, and those consequences should include patient compliance, control of intraocular pressure and progression of visual field deficit, since these drive both the costs and the overall outcomes. We recognise that constructing the 'ideal' clinical outcome measure represents a major challenge to researchers. As such, we have outlined a modelling framework that could be used to produce the required level of economic evidence, and ongoing clinical research (such as the Early Manifest Glaucoma Trial) could provide the validated link between intraocular pressure and disease progression, which forms an essential part of such models.

Cost-Benefit Analysis↗

The design and implementation of a regional economic-demographic simulation model.

The management of urban growth patterns in the United States in order to maximize the benefits of public and private investments in urban areas is examined. The authors present "the results of a modelling design effort to link a hybrid regional input-output model to demographic, labor force and energy models for use in planning in the San Francisco Bay Region. Extensive use of system feedback is a major component of this research effort. Summary results of the model outputs are presented...."

Americas↗

Inducible defence and the social evolution of herd immunity.

Many organisms vary their level of investment in defensive characters. Protective traits may be induced upon exposure to predators or parasites. In a similar way, humans vaccinate in response to threatening epidemics. When most group members defend themselves, epidemics die out quickly because parasites cannot spread. A high level of group (herd) immunity is therefore beneficial to the group. There is, however, a well-known divergence between the optimum degree of induction for selfish individuals and the level of induction that maximizes group benefit. I develop two optimality models for the frequency of induction. The first model shows that higher relatedness favours more induction and a smaller difference between selfish and cooperative optima. The second model assumes variation in the vigour of individuals and therefore differences in the relative cost for induction. The model predicts that strong individuals induce more easily than weak individuals. Small differences in vigour cause a large divergence in the optimal levels of induction for strong and weak individuals. The concept of genetic relatedness in an evolutionary model is analogous to correlated interests and correlated strategies in an economic model of human behaviour. The evolutionary models presented here therefore provide a basis for further study of human vaccination.

Animals↗

The initial validation of a Markov model for the economic evaluation of (new) treatments for rheumatoid arthritis.

OBJECTIVE: Markov models are increasingly used in economic evaluations of (new) treatments for chronic diseases. In this study we propose a Markov model with health states defined by the disease activity score (DAS) to be used to extrapolate efficacy data from short-term clinical trials in rheumatoid arthritis to longer term cost-effectiveness results. Moreover, we perform an initial validation of this model. METHODS: To test the validity of the model, the expected disease course (according to the model) was first compared with the observed disease course in an inception cohort of newly diagnosed rheumatoid arthritis patients. Then the relationship of the health states with utility and costs was investigated. Finally, costs and QALYs were calculated for usual care of patients in the first 5 years of their disease using the model and compared with the literature. RESULTS: The model seemed to be able to extrapolate 1-year efficacy data as seen by a comparable distribution over the Markov states between the model results and the observational data. The health states had a significant relationship with costs and utility, and population characteristics had only a moderate effect on the cost and utility values of the Markov states. The distribution over the Markov states resulted in 3.266 expected QALYs per patient over 5 years. The expected medical and total costs per patient over 5 years were 6754 euro (1997 values) and 12,641 euro, respectively, for standard rheumatoid arthritis care in The Netherlands. CONCLUSION: The developed Markov model seems a valid model for use in economic evaluations in rheumatoid arthritis. The model produced similar utilities, but lower total costs, to those in previously published studies. Although the steps to develop and validate this Markov model were applied in the context of rheumatoid arthritis, they can be generalised to other chronic diseases.

Arthritis, Rheumatoid↗

Empathic neural responses are modulated by the perceived fairness of others.

The neural processes underlying empathy are a subject of intense interest within the social neurosciences. However, very little is known about how brain empathic responses are modulated by the affective link between individuals. We show here that empathic responses are modulated by learned preferences, a result consistent with economic models of social preferences. We engaged male and female volunteers in an economic game, in which two confederates played fairly or unfairly, and then measured brain activity with functional magnetic resonance imaging while these same volunteers observed the confederates receiving pain. Both sexes exhibited empathy-related activation in pain-related brain areas (fronto-insular and anterior cingulate cortices) towards fair players. However, these empathy-related responses were significantly reduced in males when observing an unfair person receiving pain. This effect was accompanied by increased activation in reward-related areas, correlated with an expressed desire for revenge. We conclude that in men (at least) empathic responses are shaped by valuation of other people's social behaviour, such that they empathize with fair opponents while favouring the physical punishment of unfair opponents, a finding that echoes recent evidence for altruistic punishment.

Brain↗

Prolonged enoxaparin therapy to prevent venous thromboembolism after primary hip or knee replacement. A cost-utility analysis.

BACKGROUND: Among patients undergoing elective total hip or knee replacement, prolonged prophylaxis with low-molecular-weight heparin significantly reduces the risk of symptomatic venous thromboembolism. Whether implementing routine prolonged prophylaxis is cost-effective remains uncertain. METHODS: We performed an economic modeling study to compare the costs and health outcomes of standard (12 days) with prolonged (42 days) enoxaparin prophylaxis against venous thromboembolism after elective total hip and knee replacement. The primary economic perspective was that of a societal healthcare payer, taking Belgium as a case country. We used cost-utility analysis, a form of cost effectiveness analysis in which costs are reported in monetary terms (euros) and health outcomes are converted into quality-adjusted life years (QALYs) gained, thereby incorporating a measure of quality of life (utility) into the health outcomes. Costs for diagnosis and treatment of proximal and distal deep vein thrombosis, pulmonary embolism, postphlebitic syndrome, and major bleeding were obtained from a Delphi panel (orthopaedic surgeons) and the official reimbursement rates (Federal Ministry of Health). QALYs for these health outcomes were based on utility scores as reported in the literature. The main outcome measure was the incremental cost-utility ratio, reported as the incremental cost per quality-adjusted life year gained (euros/QALY). The incremental cost-utility ratio refers to the amount of money needed to produce one additional QALY. We also performed sensitivity analyses on clinical and economic parameters to identify important model uncertainties. RESULTS: In the base-case analysis, incremental costs of prolonged prophylaxis amounted to 58 euros and 114 euros per patient, with an additional gain in QALY of 0.0083 and 0.0018 after total hip and knee replacement, respectively. Thus, a strategy of prolonged enoxaparin prophylaxis was associated with a cost-utility ratio of 6,964 euros/QALY and 64,907 euros/QALY after total hip and knee replacement, respectively. This tenfold difference in incremental cost-utility ratios between hip and knee replacement might have important practical implications. According to recent European guidelines, an intervention costing less than 20,000 euros per QALY is said to exhibit strong evidence for adoption, whereas one costing 20,000-100,000 euros exhibits moderate evidence for adoption. By current European guidelines, the cost of 6,964 euros and 64,907 euros per QALY gained would give strong evidence for adoption of prolonged enoxaparin prophylaxis among total hip replacement patients, but moderate evidence for adoption among total knee replacement patients. Sensitivity analyses using 20% changes from the base-case analysis showed this outcome to be robust. CONCLUSIONS: Our findings indicate that, among patients undergoing elective total hip or knee replacement, prolonged enoxaparin prophylaxis leads to increased health benefits at increased cost. Given the additional costs that healthcare decision makers in Europe are usually prepared to pay for a gain in utility, prolonged prophylaxis with enoxaparin is cost-effective after elective total hip replacement, and our data provide strong evidence for adoption of prolonged enoxaparin prophylaxis after elective total hip replacement.

Anticoagulants↗

The economic impact of blue-light filtering intraocular lenses on age-related macular degeneration associated with cataract surgery: a third-party payer's perspective.

OBJECTIVES: Epidemiological data support an association between age-related macular degeneration (AMD) and cataract surgery that may be attributed to post-operative blue light exposure. By limiting the retina's blue light exposure, new blue-light filtering intraocular lenses (BLF IOLs) have the potential to reduce the development of AMD following cataract surgery. In the current economic healthcare environment, there is increased interest in the cost impact of new medical technologies. The objective of this analysis was to evaluate the cost impact of a BLF IOL versus a non-BLF IOL in cataract surgery. METHODS: An economic model was developed to emulate three age-specific cohorts and to assess the clinical and economic outcomes over 5 years. Data from the published literature was supplemented with clinical expert opinion. Key literature inputs involved the risk of AMD after cataract surgery as well as laboratory and animal data on the effectiveness of the BLF IOL in reducing the risk of AMD. Clinical experts provided information on the management of AMD. Direct medical costs including the cost of the IOL, monitoring, and AMD prophylaxis and treatment were incorporated into the model. All costs were standardized to 2004 US dollars. Age-stratified sensitivity analyses were conducted. RESULTS: In the BLF IOL group, the 5-year age-stratified incidence of AMD ranged from 0.58 to 9.23 per 100 eyes, compared with 1.69 to 24.55 per 100 eyes in the non-BLF IOL group. The incremental cost of the BLF was offset by reduced costs associated with averted AMD treatment. Estimated savings with BLF IOLs per 100 eyes were $4275, $29 997, and $111 734 in the 55 to 64 year-old, 65 to 74 year-old, and >or= 75-year-old cohorts, respectively; these findings remained robust throughout the sensitivity analyses. CONCLUSION: Limitations of this analysis include the lack of prospective clinical trial data that definitively demonstrate the efficacy of a BLF IOL in preventing AMD. Moreover, the efficacy data used to populate the model were derived from laboratory and animal studies. Thus, based on preliminary data, this study suggests that the economic benefits of implanting BLF IOLs during cataract surgery are observed in all patients over a 5-year timeframe although cost savings are greatest in patients >or= 75 years.

Aged↗

A framework for modeling interregional population distribution and economic growth.

"An integrated model is proposed to capture economic and demographic interactions in a system of regions. This model links the interregional economic model of Isard (1960) and the interregional demographic model of Rogers (1975) via functions describing consumption and migration patterns. Migration rates are determined jointly with labor force participation rates and unemployment rates."

Demography↗

Pemetrexed disodium for the treatment of malignant pleural mesothelioma: a systematic review and economic evaluation.

OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of pemetrexed disodium in combination with cisplatin for the treatment of unresectable pleural mesothelioma in chemotherapy-naive patients. DATA SOURCES: Electronic databases were searched up to May 2005. REVIEW METHODS: The systematic review was conducted following accepted guidelines. An assessment of the economic submission received from the manufacturer of pemetrexed was also carried out. This comprised two sections, each employing an economic model. One of these models was then reformulated in order to carry out a separate exploration of economic performance. RESULTS: One randomised controlled trial comparing pemetrexed and cisplatin with cisplatin alone, and involving a total study population of 448 patients, met the inclusion criteria. Pemetrexed in combination with cisplatin in this trial showed a 2.8-month gain in median survival compared with cisplatin alone in an intention-to-treat (ITT) population (12.1 and 9.3 months, respectively, p = 0.020, hazard ratio of 0.77). During the trial, increased reporting of severe toxicity in the pemetrexed arm led to a change in the protocol to add folic acid and vitamin B12 supplementation to therapy. For fully supplemented patients (n = 331) the hazard ratio for median survival in favour of pemetrexed plus cisplatin was also comparable (0.75), but of borderline significance between treatment arms (p = 0.051). The trial inclusion criteria restricted recruitment to those with a Karnofsky performance status of 70 or greater (equivalent to ECOG/WHO 0 or 1 scales more widely used in the UK). Quality of life scores using the Lung Cancer Symptom Scale demonstrated significantly greater improvement for pain and dyspnoea for patients in the combination group compared with those in the cisplatin group. In the ITT population, the incidence of serious toxicities with pemetrexed plus cisplatin was higher compared with cisplatin alone. However, the grade 3/4 toxicities of the combination arm, particularly leucopenia, neutropenia and diarrhoea, were found to be greatly improved by the addition of vitamin B12 and folic acid. The existing published economic literature was very limited. The economic evaluation conducted by the study (and that submitted by the manufacturer) suggested that pemetrexed is unlikely to be considered cost-effective at conventionally accepted thresholds in the UK for all patients, mainly because of the high cost of pemetrexed itself compared with cisplatin. These findings were better for some patient subgroups, e.g. especially for fully supplemented (FS) patients with good performance status (0/1) and advanced disease (AD). These findings seem robust. The estimated cost-effectiveness results were for the FS population, incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) gained = pound59,600; for the FS with AD population, ICER per QALY = pound47,600; for the FS with performance status 0/1 population, ICER per QALY = pound49,800; and for the FS with performance status 0/1 and AD population, ICER per QALY = pound36,700. CONCLUSIONS: The new therapy examined in this document demonstrates an extension of life expectancy and palliation, as measured by time to progression of disease and other end-points. However, the absolute benefit obtained is small, and it needs to be weighed against the benefits of effective palliative care services. The limited benefit was also at the expense of considerable toxicity to patients. The economic evaluation conducted in this study and that of the manufacturers suggest that pemetrexed is not cost-effective at conventional thresholds for all patients. Cost-effectiveness seems better for some patient subgroups, e.g. especially for patients with good performance status and with advanced diseases, where it is estimated the ICER per QALY would be pound36,700. Given the relatively small number of patients with mesothelioma, albeit increasing, the overall budget impact of pemetrexed would be unlikely to be more than pound5 million per year at present costs. Much more research is needed into the optimum chemotherapy for patients with mesothelioma and a clear definition of what constitutes best supportive care.

Antineoplastic Agents↗

Models of man and models of policy: reflections of "Exit, Voice, and Loyalty" ten years later.

The challenge of health care policy is how to combine sensitivity to both consumer preferences (the economic model) and citizen wishes (the political model): what either wants the other may wish to deny him. Competing economic (exit) and political (voice) activities in response to deterioration in the quality of a service, however, may be an inadequate framework to encompass discontent with the complex mix of types of services offered. The "political market" in which decisions about health care are made is suggested for further exploration.

Community Participation↗