On the probability of cost-effectiveness using data from randomized clinical trials

BACKGROUND: Acceptability curves have been proposed for quantifying the probability that a treatment under investigation in a clinical trial is cost-effective. Various definitions and estimation methods have been proposed. Loosely speaking, all the definitions, Bayesian or otherwise, relate to the probability that the treatment under consideration is cost-effective as a function of the value placed on a unit of effectiveness. These definitions are, in fact, expressions of the certainty with which the current evidence would lead us to believe that the treatment under consideration is cost-effective, and are dependent on the amount of evidence (i.e. sample size). METHODS: An alternative for quantifying the probability that the treatment under consideration is cost-effective, which is independent of sample size, is proposed. RESULTS: Non-parametric methods are given for point and interval estimation. In addition, these methods provide a non-parametric estimator and confidence interval for the incremental cost-effectiveness ratio. An example is provided. CONCLUSIONS: The proposed parameter for quantifying the probability that a new therapy is cost-effective is superior to the acceptability curve because it is not sample size dependent and because it can be interpreted as the proportion of patients who would benefit if given the new therapy. Non-parametric methods are used to estimate the parameter and its variance, providing the appropriate confidence intervals and test of hypothesis

Using the net benefit regression framework to construct cost-effectiveness acceptability curves: an example using data from a trial of external loop recorders versus Holter monitoring for ambulatory monitoring of "community acquired" syncope

BACKGROUND: Cost-effectiveness acceptability curves (CEACs) describe the probability that a new treatment or intervention is cost-effective. The net benefit regression framework (NBRF) allows cost-effectiveness analysis to be done in a simple regression framework. The objective of the paper is to illustrate how net benefit regression can be used to construct a CEAC. METHODS: One hundred patients referred for ambulatory monitoring with syncope or presyncope were randomized to a one-month external loop recorder (n = 49) or 48-hour Holter monitor (n = 51). The primary endpoint was symptom-rhythm correlation during monitoring. Direct costs were calculated based on the 2003 Ontario Health Insurance Plan (OHIP) fee schedule combined with hospital case costing of labour, materials, service and overhead costs for diagnostic testing and related equipment. RESULTS: In the loop recorder group, 63.27% of patients (31/49) had symptom recurrence and successful activation, compared to 23.53% in the Holter group (12/51). The cost in US dollars for loop recording was $648.50 and$212.92 for Holter monitoring. The incremental cost-effectiveness ratio (ICER) of the loop recorder was $1,096 per extra successful diagnosis. The probability that the loop recorder was cost-effective compared to the Holter monitor was estimated using net benefit regression and plotted on a CEAC. In a sensitivity analysis, bootstrapping was used to examine the effect of distributional assumptions. CONCLUSION: The NBRF is straightforward to use and interpret. The resulting uncertainty surrounding the regression coefficient relates to the CEAC. When the link from the regression's p-value to the probability of cost-effectiveness is tentative, bootstrapping may be used

Protocol for an economic evaluation alongside the University Health Network Whiplash Intervention Trial: cost-effectiveness of education and activation, a rehabilitation program, and the legislated standard of care for acute whiplash injury in Ontario

Background: Whiplash injury affects 83% of persons in a traffic collision and leads to whiplash-associated disorders (WAD). A major challenge facing health care decision makers is identifying cost-effective interventions due to lack of economic evidence. Our objective is to compare the cost-effectiveness of: 1) physician-based education and activation, 2) a rehabilitation program developed by Aviva Canada (a group of property and casualty insurance providers), and 3) the legislated standard of care in the Canadian province of Ontario: the Pre-approved Framework Guideline for Whiplash developed by the Financial Services Commission of Ontario. Methods/Design. The economic evaluation will use participant-level data from the University Health Network Whiplash Intervention Trial and will be conducted from the societal perspective over the trial's one-year follow-up. Resource use (costs) will include all health care goods and services, and benefits provided during the trial's 1-year follow-up. The primary health effect will be the quality-adjusted life year. We will identify the most cost-effective intervention using the incremental cost-effectiveness ratio and incremental net-benefit. Confidence ellipses and cost-effectiveness acceptability curves will represent uncertainty around these statistics, respectively. A budget impact analysis will assess the total annual impact of replacing the current legislated standard of care with each of the other interventions. An expected value of perfect information will determine the maximum research expenditure Canadian society should be willing to pay for, and inform priority setting in, research of WAD management. Discussion. Results will provide health care decision makers with much needed economic evidence on common interventions for acute whiplash management. © 2011 van der Velde et al; licensee BioMed Central Ltd

Adolescent Binge Drinking Leads to Changes in Alcohol Drinking, Anxiety, and Amygdalar Corticotropin Releasing Factor Cells in Adulthood in Male Rats

Heavy episodic drinking early in adolescence is associated with increased risk of addiction and other stress-related disorders later in life. This suggests that adolescent alcohol abuse is an early marker of innate vulnerability and/or binge exposure impacts the developing brain to increase vulnerability to these disorders in adulthood. Animal models are ideal for clarifying the relationship between adolescent and adult alcohol abuse, but we show that methods of involuntary alcohol exposure are not effective. We describe an operant model that uses multiple bouts of intermittent access to sweetened alcohol to elicit voluntary binge alcohol drinking early in adolescence (∼postnatal days 28–42) in genetically heterogeneous male Wistar rats. We next examined the effects of adolescent binge drinking on alcohol drinking and anxiety-like behavior in dependent and non-dependent adult rats, and counted corticotropin-releasing factor (CRF) cell in the lateral portion of the central amygdala (CeA), a region that contributes to regulation of anxiety- and alcohol-related behaviors. Adolescent binge drinking did not alter alcohol drinking under baseline drinking conditions in adulthood. However, alcohol-dependent and non-dependent adult rats with a history of adolescent alcohol binge drinking did exhibit increased alcohol drinking when access to alcohol was intermittent. Adult rats that binged alcohol during adolescence exhibited increased exploration on the open arms of the elevated plus maze (possibly indicating either decreased anxiety or increased impulsivity), an effect that was reversed by a history of alcohol dependence during adulthood. Finally, CRF cell counts were reduced in the lateral CeA of rats with adolescent alcohol binge history, suggesting semi-permanent changes in the limbic stress peptide system with this treatment. These data suggest that voluntary binge drinking during early adolescence produces long-lasting neural and behavioral effects with implications for anxiety and alcohol use disorders

The economic value of anti-IgE in severe persistent, IgE-mediated (allergic) asthma patients : adaptation of INNOVATE to Sweden

Background: Severe allergic asthma patients may not be controlled even with guideline recommended care, including inhaled corticosteroids, long-acting beta-2 agonists, theophylline, oral steroids and anti-leukotrienes. They experience exacerbations requiring intensive healthcare use and which may be fatal. Omalizumab, a new monoclonal antibody for use in IgE-mediated allergic diseases, reduces exacerbations and daily symptoms in this patient population. The aim of this study is to estimate the cost effectiveness of adding omalizumab to optimized standard therapy (ST) in patients with severe persistent IgE-mediated (allergic) asthma. Methods:A Markov model comparing lifelong ST with a treatment period of omalizumab add-on therapy followed by ST, was developed based on efficacy data from the INNOVATE trial (28 weeks, N = 419) and Swedish life table and cost data. This model assumes that patients are at risk of having an exacerbation every 2 weeks and are at risk of dying from a clinically significant severe asthma exacerbation. Patients in a steady-state of having no exacerbations are defined to be in an 'optimized asthma control' state. Resource use data and utilities were obtained from INNOVATE and from a UK observational study. Costs from a societal perspective include estimates for drugs, routine care, exacerbations and costs in added years of life; benefits are expressed in QALYs. The response to omalizumab was evaluated after 16 weeks of trial, and non-responders stopped taking omalizumab for the remaining time. Results: Total lifetime discounted costs and QALYs on ST were 52702 euro and 11.60. Omalizumab add-on therapy cost an additional 42754 euro for 0.76 additional OALYs, resulting in an incremental cost-effectiveness ratio of 56091 euro. A probabilistic sensitivity analysis indicates that the 95% CI around the ICER is [31328 euro; 20552 euro]. One-way analyses indicate that the results are sensitive to the exacerbation-related mortality rate, the time horizon and the discount rates. Conclusions: Based on the model and the assumptions used, our results suggest that omalizumab provides cost offsets, improves quality of life and may have an attractive ICER in treating the severe allergic asthma population

The impact of internal markets on health care efficiency: evidence from health care reforms in Sweden

A purchaser/provider split together with output-based reimbursement were recently introduced by several Swedish county councils. These changes have been motivated by arguments of efficiency and consumer choice. This paper tests the null hypothesis that hospital services are provided as efficiently by county councils with internal markets and output-based reimbursement as by county councils with budget reimbursement. We first estimate technical efficiency using data envelopment analysis and then we regress the efficiency scores as the dependent variable on new internal organizations in a multiple regression by use of pooled cross-section data for the 26 county councils for two years (1993 and 1994). The results reject our null hypothesis and we conclude that the organizational changes in the county councils improve health care efficiency. Our results further indicate that the potential savings in costs due to a hypothetical switch from budget based allocation to an output based allocation is about 13%. We also found some evidence indicating that county councils with a nonsocialist political majority are relatively more efficient than those with a socialist regime and that large county councils are more efficient than small county councils.