bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early Triassic carbon isotope excursions from South China: proxies for devastation and restoration of marine ecosystems following the end‐Permian mass extinction
Authors: Jinnan Tong , Jingxun Zuo , Z.Q. Chen 
Published: May 2007

AbstractEarly Triassic carbon isotopes are measured based on 1422 carbonate bulk samples from 10 Lower Triassic sections in different palaeogeographic settings in South China. Early Triassic fluctuation ofδ13C is used as a proxy for environmental change to discuss the devastation and restoration of marine ecosystems following the biggest Phanerozoic mass extinction at the end of the Permian. Early Triassicδ13C profiles derived from various depositional settings in South China yield comparable excursion patterns. A dramatic negative shift ofδ13C across the Permian/Triassic boundary is followed by a moderate increase inδ13C values throughout the Induan. A positiveδ13C anomaly occurs near the Induan/Olenekian boundary, followed by a Smithian interval of lowerδ13C values. A distinct positive shift inδ13C coincides with the Smithian/Spathian boundary, and is followed by a high Spathian plateau ofδ13C values. Thus the distinctδ13C anomalies coincide well with key stratigraphic boundaries.Early Triassic intervals of lowδ13C values correspond to a decline in benthic generic diversity in South China and intervals of highδ13C values are coupled with an increase in biodiversity. The Early Triassic fluctuations ofδ13C profiles are good proxies for perturbations of ecologic environments, indicating multiple phases of devastation–restoration of marine ecosystems punctuated by several unexpected extraneous events such as volcanic activity. The initial restoration of marine ecosystems may have occurred earlier in the Induan and the ecosystems were subsequently destroyed during the Smithian. Biotic and environmental recoveries occurred at the Spathian, while the ecosystems eventually returned to normal levels in the early Middle Triassic. Copyright © 2007 John Wiley & Sons, Ltd.
Screening for diabetic retinopathy: A relative cost‐effectiveness analysis of alternative modalities and strategies
Authors: Sculpher M. J. , Buxton M. J. , Ferguson B. A. , Spiegelhalter D. J. , Kirby A. J. 
Published: May 2007

AbstractDiabetic retinopathy is the most common cause of blindness among adults of working age in the UK. If the disease is detected early effective treatment can be provided and this has resulted in calls for a systematic national screening programme. Using data on the screening of 3423 diabetics collected as part of an experimental programme in three UK centres, the relative cost‐effectiveness of various screening options is assessed. The paper utilises direct evidence on a number of single modality screening options, including ophthalmoscopy undertaken by general practitioners or ophthalmic opticians, and non‐mydriatic photography. With the objective of increasing the sensitivity of screening and using data collected in the study, options based on two further potential screening strategies are modelled and evaluated: combined screening using both ophthalmoscopy and non‐mydriatic photography; and selective screening where high‐risk diabetics are directly referred to an ophthalmologist and lowrisk cases are either left unscreened or are screened by one of the single or combined modality screening options. Given the objective of early detection, effectiveness is assessed in terms of the sensitivity and specificity of the referral decisions of screening options. Both health service and private resource costs of the various screening options are estimated, the latter in terms of travel and the opportunity cost of time. Cost effectiveness is evaluated in terms of the expected cost per true positive case of diabetic retinopathy referred by the screening options. To narrow the choice between the options, those subject to three‐way domination with respect to the three choice variables of sensitivity, specificity and expected cost per true positive are excluded. Amongst the remaining options, the choice is dependent on the trade‐off between the higher specifics of unselective single modality screening options and the higher sensitivities and lower expected costs per true positive case detected of combined modality and selective screening options.
Cost savings in mass population screening for colorectal cancer resulting from the early detection and excision of adenomas
Authors: Whynes David K. , Walker Andrew R. , Hardcastle Jack D. 
Published: May 2007

AbstractThe widely‐accepted hypothesis of a development sequence from colorectal adenoma to carcinoma is felt by clinicians to legitimate adenoma excision during routine colonoscopic investigation. Using published data on adenoma development, and adenoma prevalence data derived from the Nottingham colorectal cancer screening trial, the number of carcinomas prevented by early excision as a result of screening is predicted. The cost‐effectiveness of early excision is then evaluated with reference to the expected treatment costs saved. These cost savings are found to represent a discount on the overall costs of mass population screening for colorectal cancer.
Forces for reforming the U.S. health care system: A review of the cost and access issues
Authors: Browning Susan M. 
Published: May 2007

AbstractIn recent years, a spate of health care reform proposals have emerged on the American agenda. Although the elements of the reform proposals often vary substantially, most of the initiatives are fuelled by two common concerns: rising health care expenditures and a growing uninsured population. National health spending, for example, commands an increasing share of U.S. gross national product despite numerous cost‐containment efforts initiated by public and private payers throughout the 1980s. And the uninsured population continues to grow—by an estimated 30 percent between 1978 and 1989. To facilitate understanding of the public policy options being considered to address these concerns, the article examines U.S. health care expenditure data and some of the causes of rising health care costs. The article also discusses the demographic characteristics of the uninsured population, the reasons why they lack health coverage, and the health consequences associated with being uninsured.
Proposals to reform the U.S. health care system: A critical review
Authors: Gaffney John C. , Browning Susan M. , Hirshfeld Edward B. 
Published: May 2007

AbstractThe objective is to provide an overview and analysis of the current discussion of ways to reform the U.S. health care system. A common analytic framework is needed to evaluate the alternative approaches that are being advocated. Such a framework, organized around seven general questions, is developed and discussed. The analytic framework is then applied to five specific reform proposals, selected to be representative of the range of options being considered. The results are used to identify the basic choices that are inherent in the current discussion of health system reform. A discussion of the political realities of the health system reform movement in the U.S. concludes that an incremental reform measure will be implemented at the federal level in the near future and that the reform measure will give the federal government increased control over the health care sector. However, the pressure for more fundamental reform will continue to grow.
Pooling international health care expenditure data
Authors: Gerdtham Ulf‐G. 
Published: May 2007

AbstractThe purpose of this paper is twofold. The first is to analyse the statistical relationship between real health care expenditure per capita and aggregate income, public share in finance, age‐dependency ratio and inflation. The second purpose deals with methodological problems involved in pooling health care expenditure data. The empirical work is based on pooled cross‐sectional, time‐series data for 22 OECD countries from 1972 to 1987. Public finance share and inflation were found to be associated with lower per capita health care expenditure. No consistent correlation was found between the age‐dependency ratio and health care expenditure. Contrary to results of earlier studies, we found that health care expenditure does not appear to be income (GDP) elastic. However, the results do not appear to be robust to changes in the time periods and countries included.
The cost and efficiency of public and private health care facilities in Ogun state, Nigeria
Authors: Wouters Annemarie 
Published: May 2007

AbstractDuring the 1980s, Nigeria faced difficult economic conditions resulting in a severely constrained budget for public health services. To assess more carefully the costs and efficiency of the public and private health sectors, the Federal Ministry of Health in Nigeria undertook a comprehensive survey of health care facilities in Ogun State in 1987, the analysis of which is presented in this study. The findings suggest that there is potential to increase service delivery within existing budgets by more cost‐effective allocation of inputs. Many public and private providers are not operating at full technical capacity. It also appears that public facilities are not using cost‐minimizing combinations of high and low‐level health workers, in particular, too many low‐level staff are being used to support high‐level workers. The cost analysis indicates that there are short‐run increasing returns to scale for inpatient and nearly constant returns to scale for outpatient services. Economies of scope for joint production of inpatient and outpatient services are not being realized. A major implication of such analysis is that improved resource allocation decisions heavily depend on the existence of information systems at the health facility level which carefully integrate financial information with other appropriate and adequate measures of service inputs, health care quality, facility utilization and ultimately health status.
Sometimes sensitive, seldom specific: A review of the economics of screening
Authors: Cairns John , Shackley Phil 
Published: May 2007

AbstractAs the policy relevance of screening has increased, the application of the techniques of economic evaluation to screening has become widespread. This paper critically reviews the literature, and in so doing, highlights several ways in which future evaluations might be improved. These include: the adoption of a broader perspective regarding the questions to be addressed and the relevant margins; a reconsideration of the nature of the benefits and how they might be valued; and a greater emphasis being placed upon the role of individual behaviour and its potential impact on the outcome of economic evaluations.
Individual behaviour and tobacco consumption: A panel data approach
Authors: Labeaga Jose M. 
Published: May 2007

AbstractThis paper considers estimators of tobacco demand equations using Becker and Murphy's model of addiction with a complete panel of households for Spain. With these tools, we face two main problems: first, the endogeneity of past and future consumption and, second, the limited‐dependent variable. To control these problems simultaneously is difficult and we proceed to confront them separately. We follow an instrumental variable approach (which also allows us to control for measurement errors in variables and non‐independent effects) to tackle the first and we use a consistent within‐group procedure to obtain the parameter vector of the structural form, once we have estimated T‐Tobit models for the reduced form in order to deal with the limited‐dependent variable problem.
Econometric analyses of national health expenditures: Can positive economics help to answer normative questions?
Authors: McGuire Alistair , Parkin David , Hughes David , Gerard Karen 
Published: May 2007

AbstractThe size of national health care expenditure is an important research and policy issue. This paper reviews theoretical and empirical analyses of an implied optimal size for a health sector. Various economic theories are explicitly or implicitly invoked, but none is fully satisfactory. Theory provides, at best, a loose justification for empirical specifications of health sector behaviour. Nevertheless, this has a large and growing empirical research industry. The complexity of the issues provides an excuse for reliance on empirical analyses using ad hoc models.The paper analyses aggregate time‐series data, using the cointegration approach, on health, health care expenditures and national income. Only one national model met both statistical criteria and showed a significant relationship: between potential life years lost and health care expenditure in the UK. The case for any general relationships remains unproven.There is no objective scientific method to determine optimal health expenditure, nor should we expect one. However, positive analyses can help with normative questions. A better understanding of health expenditure determination would arise from better specification of the relationships, perhaps by analysis at a lower level of aggregation.
Health care expenditure and income in Europe
Authors: Murillo Carlos , Piatecki Cyrille , Saez Marc 
Published: May 2007

AbstractIn this work we have tried to analyse the variations in health care expenditure in all the countries of the European Community except Greece and Portugal. We have wanted to provide additional evidence on the empirical relationship between expenditure on health care and income. Our analysis, starting from the approach of Fuchs and Baumol, has been an extension of the traditional studies on health care international comparisons, in at least three directions: we have not imposed any restrictions on the price effects, we have analysed dynamic models instead of the cross‐sectional analysis and we have used proper deflators. We have deflated health care expenditure in each country by means of its sectoral price index and by the purchasing parity power of its currency, to allow international comparisons. In the former case we express health care in terms of ‘expenditure’, in the latter we express health care in terms of ‘weighted quantity’. Income elasticities, in the short and in the long‐run, have been estimated using econometric methods that allow us to obtain simultaneously equilibrium long‐run relationships, if any, and adjustment processes in the short‐run. We have found cointegrating relationships and we have estimated consistent estimators of the elasticities. The estimated income elasticities are greater than one in all the models analysed.
Financial incentives for physicians: The Quebec experience
Authors: Rochaix Lise 
Published: May 2007

AbstractThis paper presents an empirical investigation of physician labour supply, based on a two‐stage budgeting model, drawing on an analogy with consumer theory. Physicians' trade‐offs between income and leisure constitute the first stage of the decision‐making process. In turn, choices are made in the second stage concerning the choice of particular activities (hospital versus office care, for example) or procedures (ordinary versus complete medical examinations), given the total medical care activity chosen in the first stage.The objective of the study is to identify physicians' responses to exogenous shocks in the remuneration system. The focus of analysis is shifted away from the identification of Supply‐Induced Demand (SID) to a more pragmatic analysis of some of the determinants of physicians' choices. The study uses monthly activity data on a panel of 677 Québec GPs between 1977 and 1983. Quantity adjustments and drifts to more complex (and therefore better paid) procedures are evidenced, mainly in response to a fifteen month tariff‐freeze. Physicians' ability to control their own work loads is also documented, both in terms of timing and level of complexity, and expenditure caps (in the form of an individual ceiling on GPs' quarterly gross income) are found to be effective at curbing high activity rates.
Capitation payments based on prior hospitalizations
Authors: Van Vliet R. C. J. A. , van de Ven W. P. M. M. 
Published: May 2007

AbstractIn many countries the concept of capitating health care insurers is receiving increasing attention. In a competitive environment, capitation should induce insurers to concentrate more on cost containment instead of indulging in risk selection. The necessary premium‐replacing capitation payments should account for predictable variations in annual per‐person health care expenditures as far as these are related to health status. Various studies have shown that crude capitation models based on e.g. age, sex and place of residence, do not reflect expected costs accurately. This implies inefficient pricing possibly leading to risk selection and windfall profits or losses for insurers, thereby undermining the objectives of a capitation system.Using Dutch micro data on some 200,000 individuals, this article simulates various alternative capitation models based on, among others, diagnostic information from previous hospitalizations. Results suggest that the problems of both risk selection and windfall profits/losses may be mitigated substantially by using this type of information together with data on prior costs. These results are not only relevant for situations where competing insurers are capitated, as intended in the Netherlands, but also when providers are capitated, as in the UK, or when HMOs are capitated, as in the US.
The demand for health: An empirical reformulation of the Grossman model
Authors: Wagstaff Adam 
Published: May 2007

AbstractPrevious tests of Grossman's model of the demand for health have been based on Grossman's own empirical formulation. This paper argues that this formulation fails to capture the dynamic character of the model. It proposes an alternative formulation, which appears to be more consistent with Grossman's theoretical model and which may also explain the apparent rejections of the model by the data in the author's earlier empirical work. The paper also presents some empirical results obtained using the new formulation, which are, on the whole, consistent with the predictions of Grossman's theoretical model.
Clinical importance, statistical significance and the assessment of economic and quality‐of‐life outcomes
Authors: Drummond Michael , O'Brienm Bernie 
Published: May 2007

AbstractThe assessment of economic and quality‐of‐life outcomes of health care interventions is moving into a new era, with such assessments increasingly being made within the context of controlled clinical trials. Traditionally the measurement of many variables in economic evaluations, particularly costs, has been deterministic. In the context of clinical trials the measurement of variables is stochastic, with the standard principles of statistical inference being applied to analyse differences between treatments in terms of effectiveness. Economists participating in clinical research are therefore being called upon to specify the sample size for the economic component of the evaluation and to undertake statistical tests for differences in cost or cost‐effectiveness. This paper discusses the current methodological issues surrounding stochastic measurement in clinical trials, discusses the additional issues raised by the assessment of economic and quality‐of‐life outcomes and specifies the challenges facing economists if they are to answer the questions now being posed about economic analysis by statisticians and clinical researchers. It is concluded that application of the standard principles of statistical inference to economic data is not straightforward and will require value judgements to be made about statistical significance and economic importance, which may differ from those already made in purely clinical studies.
The rand 36‐item health survey 1.0
Authors: Hays Ron D. , Sherbourne Cathy Donald , Mazel Rebecca M. 
Published: May 2007

AbstractRecently, Ware and Sherbourne1 published a new short‐form health survey, the MOS 36‐Item Short‐Form Health Survey (SF‐36), consisting of 36 items included in long‐form measures developed for the Medical Outcomes Study. The SF‐36 taps eight health concepts: physical functioning, bodily pain, role limitations due to physical health problems, role limitations due to personal or emotional problems, general mental health, social functioning, energy/fatigue, and general health perceptions. It also includes a single item that provides an indication of perceived change in health. The SF‐36 items and scoring rules are distributed by MOS Trust, Inc. Strict adherence to item wording and scoring recommendations is required in order to use the SF‐36 trademark. The RAND 36‐Item Health Survey 1.0 (distributed by RAND) includes the same items as those in the SF‐36, but the recommended scoring algorithm is somewhat different from that of the SF‐36. Scoring differences are discussed here and new T‐scores are presented for the 8 multi‐item scales and two factor analytically‐derived physical and mental health composite scores.
The costs and effects of open versus laparoscopic cholecystectomies
Authors: Kesteloot K. , Penninckx F. 
Published: May 2007

AbstractThe costs and effects of open versus laparoscopic cholecystectomies are compared, from the point of view of hospitals and patients, for a consecutive series of 47 patients undergoing a cholecystectomy in the University Hospital Gasthuisberg, in Belgium.For the patients the laparoscopic technique is superior, since effects are better and direct costs are lower than for the open technique.From a financial viewpoint, hospitals have to weigh the higher costs of the laparoscopic equipment against the lower variable costs due to the shorter postoperative length of stay. Total hospital costs would be lower in case all cholecystectomies were performed with the laparoscopic rather than with the open technique if at least 140 cholecystectomies are done annually with the electrocautery technique, or 300 procedures with laser.However, more recent data reveal that the operating time reduces with the number of laparoscopic procedures (learning effects), implying that the laparoscopic electrocautery procedure would already be the cheaper alternative if more than 70 cholecystectomies are done annually, if disposables are used (or if 50 procedures are done with re‐usables).It can be concluded that, once sufficient experience with laparoscopy has been achieved, most hospitals could realise cost savings by switching, as much as is medically justified, to laparoscopic procedures. This will also hold for hospitals performing few cholecystectomies, as long as re‐usables and electrocautery are used.
Cost‐benefit analysis of a national screening programme for cystic fibrosis in an israeli population
Authors: Ginsberg Gary , Blau Hannah , Kerem Eitan , Springer Chaim , Kerem Bat‐Sheba , Akstein Edna , Greenberg Alan , Kolumbos Ami , Abeliovich Devorah , Gazit Eli , Yahav Jacob 
Published: May 2007

AbstractThe recently acquired ability to identify 97% of CF carriers in an Israeli Ashkenazi population, prompts an evaluation of a nationwide screening programme. In 1993, the programme would first screen and counsel 9,261 parents, then 396 spouses of carrier parents and finally screen 16.5 fetuses where both parents are carriers. Assuming 92% of screened parents choose abortion of fetus screened positive, 2.33 cases of CF will be prevented in 1993 at a direct cost of $781,000. The $326,000 direct costs of preventing a CF case, exceed the lifetime excess direct costs per case of $297,000. However, benefits of screening also accrue to subsequent pregnancies, resulting in a direct benefit ($14.45 million) to cost ($10.39 million) ratio of 1.39/1 for the period 1993–2032. When benefits and costs resulting from mortality changes, work absences and transport costs are included, the benefit ($15.95 million) to cost ($13.88 million) ratio falls to 1.15/1. Benefit‐cost ratios are lower for other ethnic groups in Israel, due to lower carrier rates and lower mutation detection abilities. A CF screening programme will increase the freedom of individuals choice, but should be carried out carefully in order to minimize stigmatization and even discrimination against CF carriers.