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At least 649 records · Page 36Linked to original sources
PubMed2005

Parametric modelling of cost data: some simulation evidence.

Recently, commentators have suggested that the distributional form of cost data should be explicitly modelled to gain efficiency in estimating the population mean. We perform a series of simulation experiments to evaluate the usual sample mean and the mean estimator of a lognormal distribution, in the context of both theoretical distributions and three large empirical datasets. The sample mean is always unbiased, but is somewhat less efficient when the population distribution is truly lognormal. However the lognormal estimator can perform appallingly when the true distribution is not lognormal. In practical situations, where the true distribution is unknown, the sample mean generally remains the estimator of choice, especially when limited sample size prohibits detailed modelling of the cost data distribution.

Clinical Trials as Topic↗
PubMed2005

Estimating mean QALYs in trial-based cost-effectiveness analysis: the importance of controlling for baseline utility.

In trial-based cost-effectiveness analysis baseline mean utility values are invariably imbalanced between treatment arms. A patient's baseline utility is likely to be highly correlated with their quality-adjusted life-years (QALYs) over the follow-up period, not least because it typically contributes to the QALY calculation. Therefore, imbalance in baseline utility needs to be accounted for in the estimation of mean differential QALYs, and failure to control for this imbalance can result in a misleading incremental cost-effectiveness ratio. This paper discusses the approaches that have been used in the cost-effectiveness literature to estimate absolute and differential mean QALYs alongside randomised trials, and illustrates the implications of baseline mean utility imbalance for QALY calculation. Using data from a recently conducted trial-based cost-effectiveness study and a micro-simulation exercise, the relative performance of alternative estimators is compared, showing that widely used methods to calculate differential QALYs provide incorrect results in the presence of baseline mean utility imbalance regardless of whether these differences are formally statistically significant. It is demonstrated that multiple regression methods can be usefully applied to generate appropriate estimates of differential mean QALYs and an associated measure of sampling variability, while controlling for differences in baseline mean utility between treatment arms in the trial.

Cost-Benefit Analysis↗
PubMed2005

Stochastic league tables: an application to diabetes interventions in the Netherlands.

The aim of this paper is to discuss the use of stochastic league tables approach in cost-effectiveness analysis of diabetes interventions. It addresses the common grounds and differences with other methods of presenting uncertainty to decision-makers. This comparison uses the cost-effectiveness results of medical guidelines for Dutch diabetes type 2 patients in primary and secondary care. Stochastic league tables define the optimum expansion pathway as compared to baseline, starting with the least costly and most cost-effective intervention mix. Multi-intervention cost-effectiveness acceptability curves are used as a way to represent uncertainty information on the cost-effectiveness of single interventions as compared to a single alternative. The stochastic league table for diabetes interventions shows that in case of low budgets treatment of secondary care patients is the most likely optimum choice. Current care options of diabetes complications are shown to be inefficient compared to guidelines treatment. With more resources available one may implement all guidelines and improve efficiency. The stochastic league table approach and multi-intervention cost-effectiveness acceptability curves in uncertainty analysis lead to similar results. In addition, the stochastic league table approach provides policy makers with information on affordability by budget level. It fulfils more adequately the information requirements to choose between interventions, using the efficiency criterion.

Clinical Protocols↗
PubMed2005

Correcting for compensating mechanisms related to productivity costs in economic evaluations of health care programmes.

In the economic evaluation of health care programmes, productivity costs are often estimated using patients' wages for the period of absence. However, the use of such methods for short periods of absence is controversial. A previous study found that short-term absence is often compensated for during normal working hours and therefore does not lead to productivity losses. As such, the application of any approach almost certainly overestimates productivity costs. In this study, we examined the productivity costs for five different patient populations and one employee population, using the classical method and by identifying when extra effort was needed. In general, the results showed that productivity costs based on identifying extra effort were 25-30% of the classical estimates. For absences of just one day, productivity costs were relevant in only 17-19% of cases. For absences of two weeks or longer, productivity costs were relevant in 35-39% of cases. Measurement of the compensating mechanisms seemed to be valid, since there is considerable agreement between the opinion of supervisors and their employees about whether compensation covers productivity costs. There was much less agreement between supervisors and their employees on specific compensating mechanisms, however. The measurement of compensating mechanisms also seemed to be valid, because--as expected--different compensating mechanisms were reported for different occupations. In our study populations, compensating mechanisms appeared to differ with occupational characteristics, like part-time work, managerial work and shift work.

Absenteeism↗
PubMed2005

'Threats' to and hopes for estimating benefits.

In a recent paper in this journal, Andrew Lloyd reviewed some potential threats to the estimation of health care benefits in monetary terms. Particular emphasis was placed on the extent to which the use of non-compensatory heuristics may distort the results. Although it is useful to be reminded of these problems, Lloyd's paper does not do justice to the attention such issues have already received, and continue to receive, within Health Economics. The aim of this paper is twofold. Firstly, it seeks to provide a more balanced and comprehensive view of the evidence by considering some of the methodological work that health economists have conducted in many of the areas pointed out by Lloyd. Secondly, and more importantly, it suggests ways to combine the economic and psychological views of human decision-making, providing a much more positive perspective to all those researchers out there who recognize the necessity of using stated preference methods to inform health policy.

Choice Behavior↗
PubMed2005

State motor vehicle laws and older drivers.

After teenage males, elderly individuals have the highest per capita motor vehicle fatality rate in the United States. Surprisingly, there has been only limited work examining the effect of state motor vehicle laws on older driver fatalities. This paper uses state-level data from the 1985-2000 Fatality Analysis Reporting System to examine the effects of changes in state laws dealing with license renewal, seatbelt use, speed limits, and driving while intoxicated on fatalities among drivers and others aged 65 and over. Negative binomial regressions are estimated using alternatively state and year fixed effects, or age and year fixed effects. In-person license renewal reduced fatalities among the oldest drivers, but vision tests, road tests and the length of the license renewal cycle generally did not. In terms of policies that apply to all drivers, seatbelt laws, particularly with primary enforcement, were generally the only policies that reduced older driver fatalities. These results are noteworthy because a number of policies that have been effective towards increasing younger driver safety are not relevant for older drivers, implying that policymakers must think broadly about using state laws to improve older driver safety.

Accidents, Traffic↗
PubMed2005

The welfare loss from hospital cost-shifting behavior: a partial equilibrium analysis.

Cost shifting occurs when changes in administered prices of one payer lead to compensating changes in prices charged to other payers. Microeconomic theory suggests that cost shifting can take place under limited conditions and some empirical studies indicate that that hospital cost shifting may have actually occurred at various times. This study designs a model to conceptualize and quantify the potential welfare loss caused by hospital cost shifting under idealized yet fairly plausible conditions. The resulting estimate yields only a small efficiency loss of at most, 0.84% of private hospital expenditures in the US for 1992.

Cost Allocation↗
PubMed2005

The effect of Taiwan's tax-induced increases in cigarette prices on brand-switching and the consumption of cigarettes.

The effect of raising cigarette taxes to reduce smoking has been the subject of several studies, which often treat the price of cigarettes as an exogenous factor given to smokers who respond to it by adjusting their smoking behavior. However, cigarette prices vary with brand and quality, and smokers can and do switch to lower-priced brands to reduce the impact of the tax on the cost of cigarettes as they try to consume the same number of cigarettes as they had before a tax hike. Using data from a two-year follow-up interview survey conducted before and after a new cigarette tax scheme was imposed in Taiwan in 2002, this study examines three behavioral changes smokers may make to respond to tax-induced cigarette price increase: brand-switching, amount consumed, and amount spent on smoking. These changes were studied in relation to smoker income, before-tax cigarette price, level of addiction, exposure to advertizing, and consumer loyalty. We found that smokers, depending upon exposure to advertizing, level of consumer loyalty and initial price of cigarettes, switched brands to maintain current smoking habits and control costs. We also found that the initial amount smoked and level of addiction, not price, at least not at the current levels in Taiwan, determined whether a smoker reduced the number of cigarettes he consumed.

Adolescent↗
PubMed2005

QALYs and the capability approach.

This explores the applicability of Sen's capability approach to the economic evaluation of health care programmes. An individual's 'capability set' describes his freedom to choose valuable activities and states of being ('functionings'). Direct estimation and valuation of capability sets is not feasible at present. Standard preference-based methods such as willingness to pay are feasible, but problematic due to the adaptive and constructed nature of individual preferences over time and under uncertainty. An alternative is to re-interpret the QALY as a cardinal and interpersonally comparable index of the value of the individual's capability set. This approach has limitations, since the link between QALYs and capabilities is not straightforward. Nevertheless, the QALY approach is recognisable as an application of the capability approach since it pays close attention to functionings, through the use of survey-based multi-attribute health state valuation instruments, and permits conceptions of value other than the traditional utilitarian ones of choice, desire-fulfilment and happiness. Furthermore, suitably re-interpreted, it can account for (i) non-separability between health and non-health components of value; and suitably modified it can also account for (ii) process attributes of care, which may have a direct effect on non-health functionings such as comfort and dignity, and (iii) sub-group diversity in the value of the same health functionings.

Activities of Daily Living↗
PubMed2005

Analysis of a pharmaceutical risk sharing agreement based on the purchaser's total budget.

Many public and private healthcare payers use formularies as a tool for controlling drug costs and quality. Although the price per dose is often negotiated as part of the formulary listing, payers may still face unlimited financial risk if demand is much greater than expected at the time of listing. The requirement for drug manufacturers to submit a budget impact analysis as part of the drug approval process suggests that payers are concerned not only with the cost effectiveness of a proposed drug but also with the potential increase in total expenditures that may result from new formulary listings. In this paper we define and analyze a model for financial risk sharing based on the total budget. Our analysis focuses on optimal decision making by manufacturers in the presence of a specific risk sharing agreement. We derive a manufacturer's optimal statement of budget impact and discuss several properties of the optimal solution.

Cost-Benefit Analysis↗
PubMed2005

The economic value of informal care: a study of informal caregivers' and patients' willingness to pay and willingness to accept for informal care.

We provide a new test of the feasibility of using contingent valuation to value informal care. We start with a theoretical model of informal caregiving and derive that willingness to pay depends positively on wealth and negatively on own health, whereas the effect of other's health is sign-ambiguous. These predictions are tested in two new data sets on patients' and caregivers' willingness to pay (WTP) and willingness to accept (WTA) for informal care. The data are generally consistent with the theoretical predictions: wealth generally has a positive impact and own health a negative impact. Other's health has a mixed effect. We find only small differences between WTP and WTA. Our findings suggest that contingent valuation may be a useful technique to value informal care in economic evaluations of health care.

Aged↗
PubMed2005

Empirical investigation of experimental design properties of discrete choice experiments in health care.

Experimental design is critical to valid inference from the results of discrete choice experiments (DCEs). In health economics, DCEs have placed limited emphasis on experimental design, typically employing relatively small fractional factorial designs, which allow only strictly linear additive utility functions to be estimated. The extensive literature on optimal experimental design outside health economics has proposed potentially desirable design properties, such as orthogonality, utility balance and level balance. However, there are trade-offs between these properties and emphasis on some properties may increase the random variability in responses, potentially biasing parameter estimates.This study investigates empirically the design properties of DCEs, in particular, the optimal method of combining alternatives in the choice set. The study involves a forced choice between two alternatives (treatment and non-treatment for a hypothetical health care condition), each with three, four-level, alternative-specific attributes. Three experimental design approaches are investigated: a standard six-attribute, orthogonal main effects design; a design that combines alternatives to achieve utility balance, ensuring no alternatives are dominated; and a design that combines alternatives randomly. The different experimental designs did not impact on the underlying parameter estimates, but imposing utility balance increases the random variability of responses.

Adolescent↗
PubMed2005

GP reimbursement and visiting behaviour in Ireland.

In Ireland, approximately 30% of the population receive free GP services (medical card patients) while the remainder (private patients) must pay for each visit. In 1989, the manner in which GPs were reimbursed by the State for their medical card patients was changed from fee-for-service to capitation while private patients continued to pay on a fee-for-service basis. Concerns about supplier-induced demand were in part responsible for this policy change. The purpose of this paper is to examine the extent to which the utilisation of GP services is influenced by the reimbursement system facing GPs, by comparing visiting rates for the two groups before and after this change. Using a difference-in-differences approach on pooled micro-data from 1987, 1995 and 2000, we find that medical card eligibility has a consistently positive and significant effect on the utilisation of GP services. However, the differential in visiting rates between medical card patients and others did not narrow between 1987 and 1995 or 2000, as might have been anticipated if supplier-induced demand played a major role prior to the change in reimbursement system.

Adult↗
PubMed1992

Human leukocyte antigen typing of siblings in hereditary hemochromatosis: a cost approach.

To assess the clinical value of human leukocyte antigen typing in the diagnosis and management of hereditary hemochromatosis, 105 siblings of 35 proband cases of hemochromatosis were retrospectively analyzed to study whether the exclusion of human leukocyte antigen typing would have adversely affected management. All siblings and probands had already been tested for human leukocyte antigen-A and human leukocyte antigen-B typing, serum ferritin and transferrin saturation. The median age of siblings was 55 yr (range = 11 to 82). Siblings were categorized according to putative genotype (homozygote, heterozygote and normal) using human leukocyte antigen typing. Phenotypic expression of hemochromatosis was considered to be iron overload as indicated by an elevated ferritin (male = greater than 350 micrograms/L, female = greater than 200 micrograms/L) and/or transferrin saturation (greater than 55%). Six of 37 homozygotes had a normal ferritin and transferrin saturation, with five of these patients under 32 yr old. No putative heterozygotes with both an abnormal ferritin and transferrin saturation were seen, although 12 of 48 (25%) heterozygotes had either an elevated ferritin or transferrin saturation. Twenty of 20 normal siblings had a normal ferritin and transferrin saturation. To assess the cost of screening with and without human leukocyte antigen typing, a cost model simulation was used that compared the costs of both methods in a hypothetical family (proband, homozygote, heterozygote and normal sibling).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

The public and private sectors in health: economic issues.

Major changes in the public/private mix of health services are occurring in many countries. These changes may be analysed by examining the financing and provision of services and subsidization of the purchase of the factors of production. The public sector and not-for-profit and for-profit elements of the private sector must be viewed as separate entities in such analyses due to their differing objectives, motives and form of operation. The issues to be dealt with by countries in finding the public/private mix which is appropriate for their health system and achieves their objectives include efficiency, quality, regulation, equity and consumer choice and satisfaction. The recommendations for action for countries include: promoting collaboration between private and public sectors; testing different public/private mix models; identifying appropriate expansion paths for private sector services; improving information for policy and planning decisions; enhancing management capacity; and, reviewing programme and project support. International agencies also have a role in this process by supporting countries through the provision of technical assistance, financial aid, promoting policy reviews, and facilitating the sharing of information and experiences among countries concerning these public/private mix issues.

Developing Countries↗
PubMedDate not supplied

The role of user charges and structural attributes of quality on the use of maternal health services in Morocco.

Health care decision makers in settings with low levels of utilization of primary services are faced with the challenge of balancing the sometimes competing goals of increasing coverage and utilization of maternity services, particularly among the poor, with that of ensuring the financial viability of the health system. Morocco is a case in point where this policy dilemma is currently being played out. This study examines the role of household out-of-pocket costs and structural attributes of quality on the use of maternity care in Morocco using empirical data collected from both households and health care facilities. A nested logit model is estimated, and the coefficient estimates are used to carry out policy simulations of the impact of changes in the levels of out-of-pocket fees and structural attributes of quality in order to help guide policy makers responsible for the design of pending social insurance programs. The results of the paper suggest that social insurance strategies that involve increases in out-of-pocket charges in the form of copayments could be implemented without untoward effects on appropriate use of maternity care for non-poor women, but would be contraindicated for poorer and rural households.

Adolescent↗
PubMed2006

A guide to economic evaluation: methods for cost-effectiveness analysis of person-level data.

The authors introduce economic evaluation with particular attention to cost-effectiveness analysis. They begin by establishing why health care decisions should be guided by economics. They then explore different types of economic evaluations. To illustrate how to conduct and evaluate a cost-effectiveness analysis, a hypothetical study about the treatment of posttraumatic stress disorder with psychotherapy versus pharmacotherapy is considered. The authors conclude with recommendations for increasing the strength and relevance of economic evaluations.

Cost-Benefit Analysis↗