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PubMedDate not supplied

The sensitivity of substance abuse treatment intensity to co-payment levels.

This study exploits variation in co-payment levels among different contractual arrangements within a regional managed behavioral health care organization to estimate the relationship between co-payment levels for substance use treatment services and the intensity of substance use treatment. The substance use treatment benefits involved a range of co-payment levels across nearly 400 employers during the years 1993 through 1998. Multiple regression techniques were used to estimate the effect of co-payment levels on treatment intensity. The results indicate that co-payment levels had a significant negative effect on outpatient and inpatient substance use treatment. For outpatient treatment the effect on intensity implied a co-payment elasticity of -0.18, implying that moving from a $10 co-payment to a $20 co-payment would result in, for example, a reduction from 5 to 4 outpatient visits per episode. However, the effect was larger for persons with combined alcohol and drug use disorders, as they exhibited a co-payment elasticity of -0.27. For inpatient days, the co-payment elasticity was considerably smaller at -0.017. Given the benefits of maintaining persons with substance use disorders in treatment, employers may have an incentive to take steps to minimize the barriers to treatment.

Adult↗
PubMed2004

A unified convergence theory of a numerical method, and applications to the replenishment policies.

In determining the replenishment policy for an inventory system, some researchers advocated that the iterative method of Newton could be applied to the derivative of the total cost function in order to get the optimal solution. But this approach requires calculation of the second derivative of the function. Avoiding this complex computation we use another iterative method presented by the second author. One of the goals of this paper is to present a unified convergence theory of this method. Then we give a numerical example to show the application of our theory.

Algorithms↗
PubMed2003

Medical economics of whole-body FDG PET in patients suspected of having non-small cell lung carcinoma--reassessment based on the revised Japanese national insurance reimbursement system.

UNLABELLED: Focusing on the savings expected from the revised Japanese national insurance reimbursement system in the management of patients suspected of having non-small cell lung carcinoma (NSCLC), cost-effectiveness was assessed using decision tree sensitivity analysis on the basis of the 2 competing strategies of whole-body FDG PET (WB-PET) and conventional imaging (CI). METHODS: A WB-PET strategy that models dependence upon chest FDG PET scan, WB-PET scan, and brain MR imaging with contrast was designed. The cost of a FDG PET examination was updated and determined to be US dollar 625.00. The CI strategy involves a combination of conventional examinations, such as abdominal CT with contrast, brain MR imaging with contrast, and a whole-body bone scan. A simulation of 1,000 patients suspected of having NSCLC (Stages I to IV) was created for each strategy using a decision tree and baselines of other relevant variables cited from published data. RESULTS: By using the WB-PET strategy in place of the CI strategy for the management of patients suspected of having NSCLC in hospitals with an NSCLC prevalence of 75%, the cost saving (CS) for each patient would be US dollar 697.69 for an M1 prevalence of 20% and US dollar 683.52 for an M1 prevalence of 40%, but the CS gradually decreases as the NSCLC prevalence increases. The break-even point requires less than an 80% prevalence in order for the WB-PET strategy to gain life expectancy (LE) per patient. By using the WB-PET strategy in place of the CI strategy for the management of patients suspected of having NSCLC in hospitals with an NSCLC prevalence of 75%, the gain in LE for each patient would be 0.04 years (11.06 vs. 11.02 years) for an M1 prevalence of 20% and 0.10 years (10.13 vs. 10.03 years) for an M1 prevalence of 40%. The maximum cost of a PET study without losing LE would be US dollar 1322.68 per patient for prevalences of 75% NSCLC and 20% M1 disease. CONCLUSIONS: The present study quantitatively showed WB-PET, employed in place of CI for managing NSCLC patients, to be cost-effective in the Japanese revised insurance reimbursement system. However, the present cost is very low from the industrial viewpoint.

Carcinoma, Non-Small-Cell Lung↗
PubMed2003

Anorexia nervosa: the cost of long-term disability.

This study was performed to estimate the cost of long-term disability in people who have anorexia nervosa (AN) that live in the province of British Columbia (BC), Canada. Canada provides universal socialized health and welfare services, and each of the 10 provinces is responsible for its own funding. As the provincial government of BC does not categorize its disability payments by the cause of the disability, a survey was used to determine the rate of disability from AN. A sensitivity analysis was performed to assess the influence of variations on the yearly cost of disability in BC: the number of patients with AN was varied between 1.0 and 2.0% of the female and 0.05 and 0.1% of the male population; the percentage of patients with AN receiving disability payments was determined by the survey to be 35%; the cost of these payments was varied between the lowest and highest benefits a single person can receive from the BC provincial government; and finally, to allow for possible sampling bias and a possible lower prevalence of AN, the lower limit of the sensitivity analysis was derived by dividing the lowest estimate above by seven. The sensitivity analysis revealed that the total estimated cost of long-term disability in BC could be as low as $2.5 million (Canadian) or as high as $101.7 million per year, which is a cost of up to 30 times the total yearly cost of all tertiary care services for the treatment of eating disorders in BC. In view of this finding, an increase in funding is warranted for primary, secondary and tertiary prevention programs for AN in BC.

Adolescent↗
PubMed2006

[Health economics and HTA].

For a comprehensive health technology assessment (HTA), health economic studies are analysed as well as medical studies. Significance and effects of HTA are rather different in European countries. In Germany HTA is conducted by two official agencies: DIMDI and IQWiG. While DIMDI requires health economic assessments, IQWiG is prohibited from considering economic aspects by law (pure assessment of benefits). For the health economic assessment in HTA reports mainly secondary scientific evidence is exploited, i.e. primarily cost effectiveness and cost utility analyses. The study perspective, the study alternatives and the modelling methods are of great importance for the evaluation and have to be justified in depth. The cost effectiveness ratio and the budget impact are the most important results of the health economic assessment, which is the basis for the appraisal by the health care authorities. For this decision medical, utilitarian or other aspects like the avoidance of unwanted distribution effects are considered. On the other hand often only a few studies are available for the decision making when the appraisal has to be done. This problem might be less relevant in the near future as the number of HTAs and the number of health economic evaluations increases.

Biomedical Technology↗
PubMed2004

[When is expensive pharmacotherapy good value for the money?].

Expensive drugs are good value for money if they are effective and safe, and if they have a better cost-effectiveness ratio than the standard therapy. In this article, an overview of commonly used methods, sources and functions of health economic evaluation is presented and illustrated using clinical examples to facilitate interpretation of the health economic information.

Cost Control↗
PubMed2004

Adult mental health needs and expenditure in Australia.

BACKGROUND: Relatively little international work has examined whether mental health resource allocation matches need. This study aimed to determine whether adult mental health resources in Australia are being distributed equitably. METHOD: Individual measures of need were extrapolated to Australian Areas, and Area-based proxies of need were considered. Particular attention was paid to the prevalence of mental health problems, since this is arguably the most objective measure of need. The extent to which these measures predicted public sector, private sector and total adult mental health expenditure at an Area level was examined. RESULTS: In the public sector, 41.6% of expenditure variation was explained by the prevalence of affective disorders, personality disorders, cognitive impairment and psychosis, as well as the Area's level of economic resources and State/Territory effects. In the private sector, 72.4% of expenditure variation was explained by service use and State/Territory effects (with an alternative model incorporating service use and State/Territory supply of private psychiatrists explaining 69.4% of expenditure variation). A relatively high proportion (58.7%) of total expenditure variation could be explained by service utilisation and State/Territory effects. CONCLUSIONS: For services to be delivered equitably, the majority of variation in expenditure would have to be accounted for by appropriate measures of need. The best model for public sector expenditure included an appropriate measure of need but had relatively poor explanatory power. The models for private sector and total expenditure had greater explanatory power, but relied on less appropriate measures of need. It is concluded that mental health services in Australia are not yet being delivered equitably.

Adolescent↗
PubMed1998

Geography and mental health: a review.

In our current health care context, characterized by fiscal restraint and decentralization of accountability for health to regional authorities, geographic inequities in need, access to care, utilization, and health outcomes will come under increasing scrutiny. Knowledge gained from ecological studies about geographic disparities in mental health are likely to have important implications for policy, program planning, and resource allocations. In light of the growing relevance of the geography of mental health, this paper will review (1) selected contributions of geographic studies to the field of mental health, (2) common ecologic study approaches used in most geographic studies, (3) key conceptual and methodological challenges related to the application and interpretation of ecologic models in mental health, and (4) the wider potential of this technique for resource equity. Given the importance of geography for needs assessment and service planning, it is surprising that geographic study designs, which use ecological data, have not received greater attention as an important and viable method of assessing population mental health.

Diagnosis-Related Groups↗
PubMed1998

Estimation of direct cost and resource allocation in intensive care: correlation with Omega system.

OBJECTIVE: An instrument able to estimate the direct costs of stays in Intensive Care Units (ICUs) simply would be very useful for resource allocation inside a hospital, through a global budget system. The aim of this study was to propose such a tool. DESIGN: Since 1991, a region-wide common data base has collected standard data of intensive care such as the Omega Score, Simplified Acute Physiologic Score, length of stay, length of ventilation, main diagnosis and procedures. The Omega Score, developed in France in 1986 and proved to be related to the workload, was recorded on each patient of the study. SETTING: Eighteen ICUs of Assistance Publique-Hôpitaux de Paris (AP-HP) and suburbs. PATIENTS: 1) Hundred twenty-one randomly selected ICU patients; 2) 12,000 consecutive ICU stays collected in the common data base in 1993. MEASUREMENTS: 1) On the sample of 121 patients, medical expenditure and nursing time associated with interventions were measured through a prospective study. The correlation between Omega points and direct costs was calculated, and regression equations were applied to the 12,000 stays of the data base, leading to estimated costs. 2) From the analytic accounting of AP-HP, the mean direct cost per stay and per unit was calculated, and compared with the mean associated Omega score from the data base. In both methods a comparison of actual and estimated costs was made. RESULTS: The Omega Score is strongly correlated to total direct costs, medical direct costs and nursing requirements. This correlation is observed both in the random sample of 121 stays and on the data base' stays. The discrepancy of estimated costs through Omega Score and actual costs may result from drugs, blood product underestimation and therapeutic procedures not involved in the Omega Score. CONCLUSIONS: The Omega system appears to be a simple and relevant indicator with which to estimate the direct costs of each stay, and then to organise nursing requirements and resource allocation.

Critical Care↗
PubMed1998

The relation between TISS and real paediatric ICU costs: a case study with generalizable methodology.

OBJECTIVE: To determine the quantitative relation between the Therapeutic Intervention Scoring System (TISS) in combination with other relevant clinical variables and the real costs of (paediatric) intensive care. DESIGN: A prospective, observational study. SETTING: A Ten-bed paediatric intensive care unit in a university children's hospital. PATIENTS AND PARTICIPANTS: In a 17-months registration period we collected patient- and treatment-related data for all 611 consecutive admissions. A 21-day calibration period was used to collect detailed data to calculate the real costs of 33 consecutive admissions, in addition to the same data as in the registration period. MEASUREMENTS AND RESULTS: We used the Multi Moment Measurement method to measure time spent by nurses and physicians and medication used in the 21-day calibration period. The calibration period data set with explanatory variables including TISS was used to build a regression model to estimate nurse and physician time, which were converted to personnel costs, and to estimate medication costs. The regression models built from the calibration period were subsequently used to estimate the total costs per day and per admission in different patient groups in the registration period. CONCLUSION: It was feasible to calculate total direct medical costs based on a limited number of readily available clinical variables related to patient characteristics and treatment, of which TISS was the most important determinant. The proposed methods provide further tools for assessment of (paediatric) intensive care unit performance.

Direct Service Costs↗
PubMed2005

The need for microsimulation to evaluate osteoporosis interventions.

Simulations play an increasingly important role in the evaluation of osteoporosis interventions. Existing evaluations have been based on "reduced-form" cohort simulations that do not reflect the complexity and heterogeneity of osteoporosis and its outcomes. Such simplified models offer parsimony and ease of use, but they also are limited in their ability to explain and extrapolate outcomes in a way that is most useful for both clinical and health policy decision makers. Alternatively, evaluations could be based on "structural" microsimulations, which explicitly model the underlying biology of osteoporosis at the individual level. The structural approach presents technical challenges, including the need to obtain more-detailed data and the requirement that underlying biological models be validated. However, evaluations based on structural microsimulation may ultimately provide substantially more useful information, resulting in improved decision making.

Computer Simulation↗
PubMed2006

Cost-effectiveness of the treatment and prevention of osteoporosis--a review of the literature and a reference model.

OBJECTIVE: The purpose of the paper is to update and review the latest developments related to modelling and economic evaluation of osteoporosis in the period 2002-2005 and further to present a reference model for the assessment of the cost-effectiveness of the prevention and treatment of osteoporosis. DISCUSSION: The reference model is intended to be used for fracture specific interventions affecting the risk of fracture. An interface version and an extensive description of the model is available on the internet ( http://www.healtheconomics.se ) and also accessible via the International Osteoporosis Foundation ( http://www.osteofound.org ). The purpose of the reference model is to improve the quality and comparability of cost-effectiveness analysis in the osteoporosis field and to serve as a tool for validation of present and future cost-effectiveness models. The reference model allows the cost-effectiveness analysis to be carried out from a societal perspective including intervention, morbidity and mortality costs. The model has been extensively tested and calibrated, and meets the properties of good decision analytic modelling. The model is a state transition Markov cohort model, which is characterised by a 50-year time horizon divided into one year cycle lengths. The following health states are included: "healthy", "hip fracture", "spine fracture", "wrist fracture", "other fracture", and "dead". CONCLUSION: The model is flexible and allows for the estimation of the cost-effectiveness over different ranges for a selected number of variables (e.g., age, fracture risk, cost of intervention).

Aged↗
PubMed2001

Cost-effectiveness of preventing hip fracture in the general female population.

The aims of this study were to determine whether treatments that reduce the incidence of hip fracture might be used in the general female population rather than screening or case-finding strategies. Cost-effectiveness, measured as cost per quality-adjusted life-year (QALY) gained using threshold values for cost-effectiveness of $20,000 or $30,000/QALY gained, was assessed during and after treatment using a computer simulation model applied to the female population of Sweden. The base case assumed a 5-year intervention that reduced the risk of hip fracture by 35% during the treatment period, and an effect that reversed to the pretreatment risk during the next 5 years. Sensitivity analyses included the effects of age, different treatment costs and effectiveness. Cost-effectiveness was critically dependent upon the age and costs of intervention. Reasonable cost-effectiveness was shown even with relatively high intervention costs for women at average risk at the age of 84 years or more. For the cheapest interventions ($63/year) cost-effectiveness could be found from the age of 53 years. Variations in effectiveness (15-50% risk reduction) had marked effects on the age that treatment was worthwhile. We conclude that segments of the apparently healthy population could be advantaged by treatment if efficacy were supported by randomized controlled studies.

Age Factors↗
PubMed2000

A labor-supply analysis of cocaine self-administration under progressive-ratio schedules: antecedents, methodologies, and perspectives.

RATIONALE: Under a progressive-ratio (PR) schedule, a subject must complete increasing fixed-ratio (FR) response requirements to obtain reinforcers. Response requirements are increased until responding stops; the final ratio completed being the "break point" and providing an index of the relative effectiveness, or value, of the reinforcer to maintain behavior. OBJECTIVES: This review examines the historical and conceptual framework underlying the PR procedure and examines the concept of relative reinforcer value. Pharmacological analysis (based on receptor theory), and behavior analysis (based on microeconomic theory) are reviewed. METHODS: Using a microeconomic adaptation of the reinforcement model referred to as conservation, a mathematical model of PR performance is proposed based on the curvilinear relationship between economic supply and labor. Drug consumption and instrumental responding were assumed to reflect deviations from a balance point, defined as the levels of consumption and responding under no scheduled restraint. Data sets were re-analyzed in which several response sequences were examined in rhesus monkeys maintained on PR schedules of intravenous cocaine delivery. RESULTS: The modified conservation equation fitted the PR data accurately, and results consistent with both linear and concave labor-supply functions were obtained. These results suggest that cocaine self-administration under PR schedules conforms to labor-supply relationships characterized as inelastic (consumption is resistant to increases in schedule requirements) and unit elastic (at high response costs, consumption declines with no corresponding increase or decrease in total responding). CONCLUSIONS: The labor-supply methodology allows for a definition of the relative value of a drug reinforcer in PR studies based on changes in consumption across response costs. Specifically, relative reinforcer value is defined in terms of changes in behavior from a balance point, rather than as a property that determines the strength of the instrumental response.

Animals↗
PubMed2001

Land-use dynamics in a southern Illinois (USA) watershed.

The Cache River of southernmost Illinois is used as a case study for developing and demonstrating an approach to quantitatively link (1) national agricultural policy and global agricultural markets, (2) landowner's decisions on land use, (3) spatial patterns of land use at a watershed scale, and (4) hydrologic impacts, thus providing a basis to predict, under a certain set of circumstances, the environmental consequences of economic and political decisions made at larger spatial scales. The heart of the analysis is an estimation, using logistic regression, of the affect of crop prices and Conservation Reserve Program (CRP) rental rates on farmland owner's decisions whether to reenroll in the CRP or return to crop production. This analysis shows that reasonable ranges for crop prices (80%-150% of 1985-1995 values) and CRP rental rates (0-125% of 1985-1995 rates) result in a range of 3%-92% of CRP lands being returned to crop production, with crop prices having a slightly greater effect than CRP rental rates. Four crop price/CRP rental rate scenarios are used to display resulting land-use patterns, and their effect on sediment loads, a critical environmental quality parameter in this case, using the agricultural non point source (AGNPS) model. These scenarios demonstrate the importance of spatial pattern of land uses on hydrological and ecological processes within watersheds. The approach developed can be adapted for use by local governments and watershed associations whose goals are to improve watershed resources and environmental quality.

Agriculture↗
PubMed2003

Economic evaluation of possible prevention of RSV-related hospitalizations in premature infants in Germany.

UNLABELLED: Palivizumab (Synagis, MedImmune Inc./Abbott Laboratories) has been shown to reduce the number of respiratory syncytial virus (RSV)-related hospitalizations in premature infants. The cost-effectiveness ratio of this prophylaxis, however, has not been evaluated in the German health-care system to date. The aim of the study was to assess the costs and benefits of Palivizumab among premature infants </=35 weeks with different risk factors. Projecting a societal perspective, we used decision analysis to compare the strategies of a prophylaxis with and without Palivizumab. Probabilities and costs of hospitalization were derived from a retrospective, population-based cohort study on 1,103 prematurely born infants primarily admitted to nine neonatologic care units in southern Germany between November 1998 and October 1999. Costs of prophylaxis were based on hospital sources. Efficacy of prophylaxis and estimates of RSV mortality were derived from the literature. Effectiveness was defined as the number of averted hospitalizations. The cost-effectiveness ratio of Palivizumab varied strongly among the different risk groups. While demonstrating no net cost savings related to RSV prophylaxis for any of the risk groups analyzed, Palivizumab showed the best cost-effectiveness ratio among male infants with chronic lung disease, discharge from primary neonatal care between October and December, and the presence of siblings visiting a day-care group. One averted hospitalization in this high-risk group was associated with costs of Euro 6,639 (number needed to treat (NNT): 4). For infants in other risk groups, the ratios varied from Euro 25,288 (NNT: 8) to Euro 204,684 (NNT: 54) per hospitalization averted. The cost-effectiveness ratios were sensitive to varying assumptions about probabilities and costs of rehospitalization, efficacy, and costs of Palivizumab prophylaxis. CONCLUSIONS: The results of this cost-effectiveness analysis do not justify the widespread use of Palivizumab among preterm infants. Lowering the costs of prophylaxis would be the most direct way to improve the cost-effectiveness ratio of Palivizumab.

Antibodies, Monoclonal↗