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PubMed2005

Approximating pollution abatement costs via alternative specifications of a multi-output production technology: a case of the US electric utility industry.

Using a panel of observations from the US electric utility industry, we analyze the output set frontiers that are produced by modeling the technology with different functional forms. Our specifications rely on a series of mapping regimes, based on the paths in which the outputs are scaled toward the frontier, and their outcomes are assessed against the general axiomatic framework of the production model. We demonstrate that different parameterization methodologies produce different empirical analogues of the output set and, as a consequence, can generate rather different estimates of the shadow prices of socially undesirable outputs, or 'bads,' as well. We benchmark our results by assessing the shadow price estimates, often interpreted as the opportunity cost of pollution reduction, against the market prices of pollution permits. The outcomes of our analysis suggest that the estimate of the output set boundary varies with the choice of a parameterization technique, which provides a possible explanation for the sizeable differences between the shadow prices of bads reported in the literature. We also demonstrate that among a variety of existing parametric methodologies no single technique is superior to all others.

Cost-Benefit Analysis↗
PubMed2006

Resource exploitation and cross-region growth trajectories: nonparametric estimates for Chile.

As a sector of primary concern for national development strategies, mining keeps stimulating an intensive debate in Chile, regarding its role for long-term growth. Partly drawn on theoretical contributions to growth and mineral resource accounting, this analysis assesses patterns of economic growth across Chilean regions. The theoretical and methodological rationale for focusing on weak sustainability, by testing convergence across regions in a distribution dynamics perspective, is first discussed. This is followed by a brief review of policy issues and previous empirical findings of concern to Chile's mining and regional growth. Panel data over the period 1960-2001 are analysed, with growth measured in terms of both income per capita as such, and sustainable measures of this variable. Kernel density and quantile regression estimates indicate persistent bimodal (if not possibly trimodal) distribution of nationally standardised regional incomes per capita, whereby conditions for cross-region convergence are matched only within the inner range of this distribution.

Chile↗
PubMed2003

Hospital consolidation and costs: another look at the evidence.

We investigate whether pairwise hospital consolidation leads to cost savings. We use a unified empirical methodology to assess both systems and mergers. Our comparison group for each consolidation consists of 10 'pseudo-mergers' chosen based on propensity scores. Cost function estimates reveal that consolidation into systems does not generate savings, even after 4 years. Mergers in which hospitals consolidate financial reporting and licenses generate savings of approximately 14%: 2, 3, and 4 years after merger. The system consolidation and merger results are very robust to changes in the specification and the sample.

Cost Savings↗
PubMed2003

Why did employee health insurance contributions rise?

We explore the causes of the dramatic rise in employee contributions to health insurance over the past two decades. In 1982, 44% of those who were covered by their employer-provided health insurance had their costs fully financed by their employer, but by 1998 this had fallen to 28%. We discuss the theory of why employers might shift premiums to their employees, and empirically model the role of four factors suggested by the theory. We find that there was a large impact of falling tax rates, rising eligibility for insurance through the Medicaid system, rising medical costs, and increased managed care penetration. Overall, this set of factors can explain more than one-half of the rise in employee premiums over the 1982-1996 period.

Cost Allocation↗
PubMed2003

Health anxiety and patient behavior.

Economic models of patient decision-making emphasize the costs of getting medical attention and the improved physical health that results from it. This note builds a model of patient decision-making when fears or anxiety about the future-captured as beliefs about next period's state of health-also enter the patient's utility function. Anxiety can lead the patient to avoid doctor's visits or other easily available information about her health. However, this avoidance cannot take any form: she will never avoid the doctor with small problems, and under regularity conditions she will never go to a bad doctor to limit the information received.

Adult↗
PubMed2003

The effect of cigarette excise taxes on smoking before, during and after pregnancy.

Recent analyses suggest that cigarette excise taxes lower prenatal smoking. It is unclear, however, whether the association between taxes and prenatal smoking represents a decline among women of reproductive age or a particular response by pregnant women. We address this question directly with an analysis of quit and relapse behavior during and after pregnancy. We find that the price elasticity of prenatal quitting and postpartum relapse is close to one in absolute value. We conclude that direct financial incentives to stop smoking during and after pregnancy should be considered.

Female↗
PubMed2003

Welfare reform and health insurance coverage of low-income families.

We study whether welfare reform adversely affected the health insurance coverage of low-educated single mothers and their children. Specifically, we investigate whether changes in the welfare caseload during the 1990s were associated with changes in Medicaid participation, private insurance coverage, and the number of uninsured among single mothers and their children. Estimates suggest that between 1996 and 1999, the 42% decrease in the welfare caseload was associated with the following changes in insurance coverage among low-educated, single mothers: a 7-9% decrease in Medicaid coverage; an increase in employer-sponsored, private insurance coverage of 6%; and a 2-9% increase in the proportion uninsured. Among children of low-educated, single mothers, effects were somewhat smaller. Since welfare policy was responsible for only part (e.g. one-third) of the decline in the caseload, welfare reform per se had significantly smaller effects on the health insurance status of low-income families. However, we found limited evidence that changes in the caseload due to state and federal welfare policy had fewer adverse consequences on insurance status than changes in the caseload due to other factors. This implies even smaller effects of welfare reform.

Adolescent↗
PubMed2003

Service-level selection by HMOs in Medicare.

In the federal Medicare program, contracting health maintenance organizations (HMOs) are paid on a capitated basis. There has long been concern that an "adverse selection" of risks remain in the traditional fee-for-service (FFS) sector, since beneficiaries with low costs may leave the FFS sector and join the HMOs. The distortion associated with this form of selection is that health plans may design their mix of health care services in order to effectuate favorable selection. This paper scrutinizes patterns of HMO membership and costs by service in the FFS sector for evidence consistent with the hypothesis that HMOs engage in service-level product distortion. We develop a multi-service model of choice between FFS and HMOs and show that if the HMO sector is underproviding (overproviding) a service relative to the FFS sector, we should observe a positive (negative) correlation between the HMO market share and average costs of those remaining in the FFS sector. We estimate the correlation between the HMO market share and the average FFS costs for different health care services using Medicare data for 1996. We find evidence indicating that there exists significant service-level selection by HMOs.

Aged↗
PubMed2004

On estimators of medical costs with censored data.

In the assessment of cost-effectiveness of alternative medical technologies, it is necessary to estimate the mean total cost per patient over the relevant patient population. Where information about costs comes from a clinical trial with censored data, care is needed to estimate mean total costs. We examine the theoretical connections between the two most widely used of a growing range of nonparametric estimators of costs under censoring. By clarifying the relationships between these simple methods we hope to make them more accessible and to facilitate the take-up of more sophisticated techniques. Recommendations are offered regarding the most appropriate of the available methods, but also on the potential for greater efficiency through parametric modelling.

Cost-Benefit Analysis↗
PubMed2003

The link between public and private insurance and HIV-related mortality.

As policymakers consider expanding insurance coverage for the human immunodeficiency virus (HIV+) population, it is useful to ask whether insurance has any effect on health outcomes, and, if so, whether public insurance is as efficacious as private insurance in preventing premature death. Using data from a nationally representative cohort of HIV-infected persons receiving regular medical care, we estimate the impact of different types of insurance on mortality in this population. Our main findings are that (1) ignoring observed and unobserved health status misleads one to conclude that insurance may not be protective for HIV patients, (2) after accounting for observed and unobserved heterogeneity, insurance does protect against premature death, and (3) private insurance is more effective than public insurance. The better performance of private insurance can be explained in part by more restrictive Medicaid prescription drug policies that limit access to highly efficacious treatment.

Adolescent↗
PubMed2004

Estimating medical care costs under conditions of censoring.

A number of non-parametric estimators have been proposed to calculate average medical care costs in the presence of censoring. This paper assesses their performance both in terms of bias and efficiency under extreme conditions using a medical dataset which exhibits heavy censoring. The estimators are further investigated using artificially generated data. Their variances are derived from analytic formulae based on the estimators' asymptotic properties and these are compared to empirically derived bootstrap estimates. The analysis revealed various performance patterns ranging from generally stable estimators under all conditions considered to estimators which become increasingly unstable with increasing levels of censoring. The bootstrap estimates of variance were consistent with the analytically derived asymptotic variance estimates. Of the two estimators that performed best, one imposes restrictions on the censoring distribution while the other is not restricted by the censoring pattern and on this basis the second may be preferred.

Costs and Cost Analysis↗
PubMed2004

Effect of drive-through delivery laws on postpartum length of stay and hospital charges.

Postpartum hospital length of stay fell rapidly during the 1980s and 1990s, perhaps due to increased managed care penetration. In response, 32 states enacted early postpartum discharge laws between 1995 and 1997, and a federal law took effect in 1998. We analyze how these laws changed length of stay and hospital charges, using a national discharge database. Difference-in-differences models show that the laws increased both length of stay and hospital charges, but the magnitude of this effect is much smaller than has been estimated in previously reported case studies. Furthermore, we find that effects vary by law details, that ERISA diluted the law effects, and that law effects partially spilled over to unregulated Medicaid births.

Employee Retirement Income Security Act↗
PubMed2004

An optimal contract approach to hospital financing.

Existing models of hospital financing advocate mixed schemes which include both lump-sum and cost-based payments. The doctor is generally the unique decision maker, which is unrealistic in a hospital setting where both managers and doctors are involved. This paper develops a model in which managers and doctors are responsible for different decisions within the hospital. In this model, public authorities who provide the financing, hospital managers who allocate resources within the hospital, and doctors who assign patients to either a low-tech or a high-tech therapy have information of increasing quality on the casemix of patients. The public authorities sign with hospital managers contracts specifying some lump-sum financing and some size of a high-tech equipment. In turn, managers, who know the broad mix of patients in the hospital, sign with hospital doctors contracts that specify the non-medical resources allocated to this facility as well as some remuneration. Doctors, who know each patient's illness severity, select the patients to be treated by the high-tech facility, and receive from public authorities some fee-for-service payment that is differentiated according to the low- or high-tech treatment used for curing their patients. What emerges is a two-stage agency problem in which contracts are designed to elicit information in the most efficient way.

Contract Services↗
PubMed2004

A longitudinal study of the effects of age and time to death on hospital costs.

Recent studies indicate that approaching death, rather than age, may be the main demographic driver of health care costs. Using a 29-year longitudinal English dataset, this paper uses more robust methods to examine the effects of age and proximity to death on hospital costs. A random effects panel data two-part model shows that approaching death affects costs up to 15 years prior to death. The large tenfold increase in costs from 5 years prior to death to the last year of life overshadows the 30% increase in costs from age 65 to 85. Hence, expenditure projections must consider remaining life expectancy in the populations.

Age Distribution↗
PubMed2004

On the international stability of health care expenditure functions: are government and private functions similar?

This paper studies the stability of health care expenditure functions in a sample of OECD countries. We adopt the cointegration approach and the results show that there is a long-term relationship between total health care expenditure (HCE) and gross domestic product (GDP). However, the existence of cointegration is only shown when we admit the presence of some changes in the elasticities of the model. Our results also provide evidence against the existence of a unique relationship between health and GDP for the sample. Thus, we can conclude that the differences in health systems may cause differences in the aggregate functions. Additionally, we examine aggregate health functions for government (GHCE) and private expenditures (PHCE), again finding evidence of different patterns of behaviour. Finally, we open a discussion on the character of health as a necessary or luxury good. In this context, we find differences between the government and the private function. In order to illustrate these findings, we propose a theoretical model as an example of the influence of political decisions on income elasticity.

Global Health↗
PubMed2004

Valuing health care using willingness to pay: a comparison of the payment card and dichotomous choice methods.

This paper compares willingness to pay (WTP) estimates generated from the dichotomous choice (DC) and payment card (PC) approaches. In a split-sample WTP experiment concerned with allocating scarce health care resources across three health care interventions, the DC approach is shown consistently to generate larger welfare estimates than the PC. Observed difference between PC and DC experiments cannot be explained by the inclusion of non-demanders or methods of statistical analysis but may be partly explained by "yea-saying". No evidence of range bias or mid-point bias was found with PC responses. Data were also collected on respondents' ordinal rankings of the three interventions and person-trade-offs (PTOs). Neither of these approaches converged with WTP. Future work must address the decision heuristics individuals employ when responding to valuation experiments.

Air Ambulances↗
PubMed2004

Is cigarette smoking in poorer nations highly sensitive to price? Evidence from Russia and China.

We examine cigarette demand in China and Russia using longitudinal micro-level household and community surveys. Previous developing-country price elasticity estimates of around -0.75 have been larger than United States estimates of about -0.4, but the former have relied primarily on aggregate data. In contrast, our micro-level price elasticity estimates in China and Russia range from 0 to -0.15. Thus, raising prices in poorer countries may not reduce smoking to the degree previously suggested.

Adult↗
PubMed2004

Within-year variation in hospital utilization and its implications for hospital costs.

Variability in demand for hospital services may have important effects on hospital costs, but this has been difficult to examine because data on within-year variations in hospital use have not been available for large samples of hospitals. We measure daily occupancy in California hospitals and examine variation in hospital utilization at the daily level. We find substantial day-to-day variation in hospital utilization, and noticeable differences between hospitals in the amount of day-to-day variation in utilization. We examine the impact of variation on hospital costs, showing that increases in variance are associated with increases in hospital expenditures, but that the effects are qualitatively modest.

Bed Occupancy↗