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PubMed2000

[Screening for asymptomatic Chlamydia trachomatis infection in pregnancy; cost-effectiveness favorable at a minimum prevalence rate of 3% or more].

OBJECTIVE: To estimate the cost-effectiveness of antenatal screening for Chlamydia trachomatis. DESIGN: Pharmaco-economic model analysis. METHOD: The risks of C. trachomatis infection during pregnancy and of complications of the infection as well as the cost of screening for complications (pelvic inflammatory disease, chronic pelvic pain, ectopic pregnancy, infertility and neonatal pneumonia) and of treatment were estimated. Assumed were a ligase chain reaction on urine and treatment of identified infected cases with erythromycin or amoxicillin (second choice). Cost-effectiveness was calculated and presented in net direct and indirect costs per major complication averted. RESULTS: For C. trachomatis prevalences in pregnancy above 4% benefits exceed the costs. For prevalences between 2.82% and 4.00% net costs are positive, but a major complication averted costs less than f 1000.-. Considering sensitivity analysis as well, screening for C. trachomatis at prevalences above 3% costs less than f 1000.-per major complication averted and might even save costs. No recent Dutch data on C. trachomatis prevalence in pregnancy are published however. CONCLUSION: Given the current information, antenatal C. trachomatis screening can be recommended from a pharmaco-economic perspective if C. trachomatis prevalence in pregnancy is 3% or more.

Adolescent↗
PubMed2004

A systematic review and economic evaluation of magnetic resonance cholangiopancreatography compared with diagnostic endoscopic retrograde cholangiopancreatography.

OBJECTIVES: To compare the clinical and cost-effectiveness of magnetic resonance cholangiopancreatography (MRCP) with diagnostic endoscopic retrograde cholangiopancreatography (ERCP) for the investigation of biliary obstruction. DATA SOURCES: Electronic bibliographic databases, the reference lists of relevant articles and various health services research-related resources. REVIEW METHODS: The data sources were searched and selected studies were assessed using quality criteria. In total, 28 prospective diagnostic studies were identified reporting several suspected conditions plus one of patient satisfaction. Analyses were then performed to establish sensitivities, specificities, likelihood ratios and confidence intervals. The relative cost-effectiveness of adopting MRCP scanning in the investigation of the biliary tree was undertaken using a probabilistic economic model. RESULTS: The median sensitivity for choledocholithiasis (13 studies) was 93% and the median specificity 94%. The median likelihood ratio for a positive value was 15.75 and for a negative value 0.08. Reported sensitivities for malignancy were somewhat lower, ranging from 81 to 86%, and specificities ranged from 92 to 100%. There was some evidence that MRCP is an accurate diagnostic test in comparison to ERCP, although the quality of studies was moderate. Claustrophobia prevented at least some patients from having MRCP in ten of the 28 studies. The other 18 studies did not mention claustrophobia. The probability of avoiding unnecessary diagnostic ERCP is estimated at 30%. These patients could avoid the unnecessary risk of complications and death associated with diagnostic ERCP, and substantial cost saving would be gained. The overall expected cost saving associated with MRCP is GBP149; the overall expected gain in quality-adjusted life-year is estimated at 0.011. CONCLUSIONS: There is some evidence that MRCP is an accurate investigation compared with diagnostic ERCP, although the values for malignancy compared with choledocholithiasis were somewhat lower. The quality of studies was moderate. The limited evidence on patient satisfaction showed that patients preferred MRCP to diagnostic ERCP. The estimated clinical and economic impacts of diagnostic MRCP versus diagnostic ERCP are very favourable. The baseline estimate is that MRCP may both reduce cost and result in improved quality of life outcomes compared with diagnostic ERCP. Further research is suggested to compare MRCP and diagnostic ERCP with final diagnosis and also with the full range of target conditions; to examine patient satisfaction and ways of reducing problems with claustrophobia; to look at protocols to help identify who could most benefit from MRCP or ERCP; to assess the relative need and urgency of patient access to magnetic resonance imaging services, and also to determine how demand would affect availability and potential cost savings.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2006

Cost-effectiveness of 4 neonatal screening strategies for cystic fibrosis.

OBJECTIVES: The purpose of this work was to assess the costs of 4 neonatal screening strategies for cystic fibrosis in relation to health effects. In each strategy, the first test was the measurement of serum concentration of immunoreactive trypsin. The second step consisted of either a second immunoreactive trypsin test (strategy 1) or a multiple mutation analysis (strategy 2). In strategies 3 and 4, a third step was added to strategy 2: a second immunoreactive trypsin test (strategy 3) or an extended mutation analysis of the cystic fibrosis gene, that is, a denaturing gradient gel electrophoresis analysis (strategy 4). METHODS: We conducted an economic-modeling exercise in the Netherlands based on published data and expert opinions. Subjects were a hypothetical cohort of 200 000 neonates, the approximate number of children born annually in the Netherlands, and we assessed the costs and number of life-years gained as a result of neonatal screening for cystic fibrosis. The costs and effects of changes in reproductive decisions because of neonatal screening were also assessed. RESULTS: Immunoreactive trypsin + immunoreactive trypsin had the most favorable cost-effectiveness ratio of 24,800 euro per life-year gained. Immunoreactive trypsin + DNA + denaturing gradient gel electrophoresis achieved more health effects than immunoreactive trypsin + DNA + immunoreactive trypsin at lower cost. The incremental costs per life-year gained of the immunoreactive trypsin + DNA + denaturing gradient gel electrophoresis strategy compared with the immunoreactive trypsin + immunoreactive trypsin strategy were 130,700 euro, whereas the incremental costs of the immunoreactive trypsin + DNA strategy compared with the immunoreactive trypsin + DNA + denaturing gradient gel electrophoresis strategy were 2,154,300 euro. When changes in reproductive decisions as a result of neonatal screening are also taken into account, neonatal screening for cystic fibrosis may lead to financial savings of approximately 1.8 million euro annually, depending on the screening strategy used. CONCLUSIONS: Cystic fibrosis screening for neonates is a good economic option, and positive health effects can also be expected. Immunoreactive trypsin + immunoreactive trypsin and immunoreactive trypsin + DNA + denaturing gradient gel electrophoresis are the most cost-effective strategies.

Cost-Benefit Analysis↗
PubMed1995

The abnormal distribution of development: policies for southern women and children.

This paper offers a feminist critique of the relationships between gender and development by exploring the intersections between three sets of debates: firstly, the relations between interventions for women and for children through the anomalous position accorded to 'the girl child' in aid and development policies; secondly, the relations between psychological and economic models of development; and thirdly, the gendered and geographical allocation of attributes and opportunities. Drawing on analyses of the 'psychological complex' the author suggests that the cultural resources that inform developmental psychological models are highly cultural and class-specific (white, middle class, of the northern hemisphere), giving rise to a globalization of development that is reinscribed within international aid and development policies. In homogenizing difference to its norms, this globalization paradoxically reproduces the north-south opposition as an expression of cultural and political imperialism. While northern children 'develop', dominant discourses of children of the South are preoccupied with 'survival'. By such means the cultural hegemony of a unitary psychology remains intact. This paper discusses the 'abnormal distribution' of development to draw attention to the ways cultural and gender inequalities flow from the norms and generalized descriptions central to the current practice of developmental psychology and to urge that this is an important site of intervention for feminists addressing gender and development issues.

Adolescent↗
PubMed1994

Graduate medical education reform. Service provision transition costs.

OBJECTIVE: To analyze the potential strategies and costs of house staff substitution under a reformed system of graduate medical education. DESIGN: An economic model using two scenarios for substitution of house staff (residents and fellows): (1) a lower-cost model under which nonphysician providers assume many house staff responsibilities, but additional aspects of their workload are taken over by staff physicians, nurses, and ancillary personnel; and (2) a higher-cost traditional model that relies more heavily on staff physicians to replace house officers. SETTING: US teaching hospitals. MAIN OUTCOME MEASURES: Projected net substitution costs of house staff on a per full-time equivalent basis and aggregate national cost estimates of substitution. RESULTS: Net annual house staff substitution costs were estimated to be $58,000 and $77,000 per replaced full-time equivalent house officer, respectively, under the two scenarios. Assuming elimination of approximately 23,200 house staff under a reformed system, total (net) substitution costs to teaching hospitals were estimated at approximately $1.4 billion to $1.8 billion nationally on an annual basis. CONCLUSIONS: Graduate medical education reform, while likely to result in substantial long-term cost savings, will necessitate transitions in service provision that are likely to generate some new costs in the short term.

Economics, Medical↗
PubMedDate not supplied

Cost-effectiveness of antihypertensive agents in patients with reduced left ventricular function.

A pharmacoeconomic primer reviews current economic models used to analyze and synthesize information that may be considered in certain health-related policies or clinical decisions. Heightened budgetary pressures concomitant with mandates for demonstrable increases in efficacy and safety have fostered greater use of cost-effectiveness analyses (CEAs) throughout the health care industry. In the field of hypertension, major clinical trials of pharmacotherapeutic regimens generally demonstrated benefit of reducing blood pressure; CEAs supplied additional data concerning the optimum selection among alternative antihypertensive therapies. As interest has focused on the preservation of left ventricular (LV) function for the best prognosis, it has become increasingly evident that not all antihypertensive regimens affect LV function in the same way. Thus CEA may be an appropriate method to evaluate these effects and facilitate the identification of a regimen that minimizes deterioration of LV function.

Antihypertensive Agents↗
PubMed1996

Dynamic competition as an exploratory model of healthcare policy for the antihypertensive market.

Dynamic competition based on innovation, rather than classical competition based on price, may better explain the research-intensive pharmaceutical market. In an exploratory comparison of these models, economic indicators of annual change in price and price elasticity of demand were tested in a repeated-measures design by analysis of variance. Between 1990 and 1992, updated US prescribing guidelines for hypertension provided a framework in which the contrast between 2 newer classes and 2 older classes of first-line therapies served as a marker for innovation. The principal hypothesis was that newer classes would be less elastic than older classes, but with such innovation-based differences eroding over time. Although temporarily greater inelasticities for newer classes supported dynamic competition, initially extreme inelasticities for newer classes indicated a market distortion or a shifting demand curve. These exploratory results, although requiring substantiation, point toward using dynamic competition in crafting healthcare policy for the pharmaceutical market.

Analysis of Variance↗
PubMed2000

Prevention and early treatment of influenza in healthy adults.

INTRODUCTION: We present three systematic reviews carried out within the Cochrane Collaboration, focusing on a different influenza intervention in healthy adults: Vaccines; Ion Channel Inhibitor antivirals and Neuraminidase Inhibitor (NIs) antivirals. The objectives were to identify, retrieve and assess all studies evaluating the effects of these interventions in prophylaxis and early treatments of influenza and the frequency of adverse events. Additionally we present the results of the economic evaluation of effective alternatives in order to define the most cost-effective intervention. The economic evaluation is set in the context of the British Army. METHODS: Studies were identified using a standard Cochrane search strategy. Any randomised or quasi-randomised studies in healthy individuals aged 14-60 years were considered for inclusion in the systematic review. Those which met inclusion criteria were assessed for quality and their data meta-analysed. The economic model was constructed using Cost-effectiveness and Cost-utility study designs. RESULTS: Live aerosol vaccines reduced cases of clinical influenza A with virological confirmation (by serology and/or viral isolation) by 48% (95%CI: 24-64%), whilst recommended inactivated parenteral vaccines have an efficacy of 68% (95%CI: 49-79%). Vaccine effectiveness in reducing clinical influenza cases (i.e. without virological confirmation) was lower, with efficacies of 13 and 24% respectively. Use of the vaccine significantly reduced time off work, but only by 0.4 days (95%CI: 0. 1-0.8 days). Analysis of vaccines matching the circulating strain gave higher estimates of efficacy, whilst inclusion of all other vaccines reduced the efficacy. When compared to placebo for the prevention of influenza, oral amantadine was 61% (95%CI: 51-69%) efficacious (RR 0.39 - 95%CI: 0.31-0.49), and oral rimantadine was 64% (95%CI: 41-78%) efficacious (RR 0.36 -95%CI: 0.22-0.59). When compared to placebo for the treatment of influenza, oral amantadine significantly shortened duration of fever (by 1.00 days - 95%CI: 0. 73-1.29), and oral rimantadine significantly shortened duration of fever (by 1.27 days - 95%CI: 0.77-1.77). When compared to placebo, NIs were 74% (95%CIs: 50-87%) effective in preventing naturally occurring cases of clinically defined influenza. In a treatment role, NIs shortened the duration of symptoms by one day (Weighted Mean Difference - 1.0; 95%CIs: -1.3 to - 0.6) when a clinical case definition is used. The economic results show that in healthy adults, inactivated vaccines appear the best buy. CONCLUSIONS: If assessed from the point of view of effectiveness and efficiency, vaccines are undoubtedly the best preventive means for clinical influenza in healthy adults. However, when safety and quality of life considerations are included, parenteral vaccines have such low effectiveness and high incidence of trivial local adverse effects that the trade-off is unfavourable. This is so even when the incidence of influenza is high and adverse effect quality of life preferences are rated low. We reached similar conclusions for antivirals and NIs even at high influenza incidence levels. On current evidence we conclude in healthy adults aged 14-60 the most cost-effective option is not to take any action.

Adolescent↗
PubMed2002

Pharmacoeconomics of cisplatin-based chemoradiation in cervical cancer: a review.

Is the use of cisplatin-based chemoradiation therapy, which has become the new standard of care for locally-advanced cervical cancer, cost-effective? To evaluate this, a pharmacoeconomic analysis of five recent Phase III trials of cisplatin-based chemoradiation for the treatment of locally-advanced cervical cancer was conducted. Using an economic model, we applied cost data to resource-use data derived from the cisplatin-based chemoradiation arms of these randomised trials. We examined the cisplatin-based chemoradiation benefits in terms of increased median survival time. Incremental costs were divided by the difference in survival to determine the cost per patient benefited. Cost per life-year gained were calculated based on both published survival and estimated survival. Costs of cisplatin-based chemoradiation therapy regimens per life-year gained varied from US$2709 - 27,882 based on published survival and US$350 - 2860 based on estimated survival. Variations in regimen cost were largely dependent on in-patient or out-patient administration costs. Costs for cisplatin and 5-flourouracil were US$10,037 per in-patient compared to US$3431 for out-patient treatment. In conclusion, cisplatin-based chemoradiation regimens increased mean survival at an acceptable cost per life-year gained in both the in-patient and out-patient settings.

Cisplatin↗
PubMed1997

Ambulatory care databases for managed care organizations.

The uses, advantages, and limitations of ambulatory care databases are discussed, and processes for extracting and using the data are described. Claims databases allow health systems, including managed care organizations, to generate descriptive statistics on patients, providers, and diseases; to conduct comprehensive cost and resource-use analyses; and to build economic models of diseases. The use of health care databases has several advantages over clinical trials, including lower data collection costs, shorter times for analysis, larger numbers of patients, and less inconvenience to patients and providers. These databases allow the effectiveness of a treatment, instead of its efficacy, to be assessed and drug-switching patterns within disease categories to be detected. This information can be used for determining the cost and outcome implications of new treatments and formulary changes, as well as for monitoring disease management programs. Limitations of health care databases include the omission of services not covered by health plans, the risk of coding errors, the absence of indicators of disease severity, and the lack of data that would assist with clinical outcome analysis. Medical and pharmacy claims data do not contain all the information contained in patients' medical records. Despite their limitations, ambulatory care databases are useful for describing patient, provider, and disease characteristics. The databases are also useful for predicting and estimating the implications of a change in the formulary, measuring the effects of treatment guidelines, and monitoring disease management programs.

Ambulatory Care Information Systems↗
PubMed2003

Cost-minimisation analysis of pegylated liposomal doxorubicin hydrochloride versus topotecan in the treatment of patients with recurrent epithelial ovarian cancer in Spain.

The study consisted of a cost-minimisation analysis since the findings from a multicentre randomised phase III trial showed that pegylated liposomal doxorubicin hydrochloride was at least as efficacious as topotecan. An economic model from the Spanish hospitals perspective was constructed to compare the costs derived from the treatment using both drugs in patients with recurrent epithelial ovarian cancer who failed a first-line platinum-containing regimen. The cost evaluation included direct medical costs: drug, drug administration and costs of managing adverse events. Estimation of resources used in managing adverse events was made retrospectively through an expert panel. Results obtained per patient were: cost of drug and administration, 8647.70 euros for pegylated liposomal doxorubicin hydrochloride and 8519.94 euros for topotecan, while cost of managing adverse events was 967.02 euros in the pegylated liposomal doxorubicin hydrochloride arm and 3304.75 euros for topotecan. The total cost per patient was therefore estimated to be 9614.72 euros for pegylated liposomal doxorubicin hydrochloride and 11 824.69 euros for topotecan, showing that pegylated liposomal doxorubicin hydrochloride produces a cost saving of 2209.97 euros per patient in comparison to topotecan. Sensitivity analyses verified the robustness of the results. These findings suggest that pegylated liposomal doxorubicin hydrochloride is an efficient therapy and can be used as a cost-saving option for treatment of patients with recurrent epithelial ovarian cancer who have failed a first-line platinum-containing regimen.

Antineoplastic Agents↗
PubMed1999

The cost-effectiveness of isotretinoin in the treatment of acne. Part 2. A chronic medication plan profiling study.

OBJECTIVES: Aspects of current clinical practice, needed for a pharmaco-economic model of isotretinoin, were determined from an acne-profiling study on chronic medication plan data. The patient sample was analysed as a whole and as two subgroups, representing isotretinoin and oral antibiotic patients. The study focused on the prevalence of the condition, patient age and gender distributions, and pharmacotherapeutic patterns and costs. METHODOLOGY: Anonymous patient records from the Pharmaceutical Benefit Management (Pty) Ltd, Cape Town, chronic medication plan were screened and analysed using descriptive and inferential statistical methods. For all hypothesis tests, the significance level (alpha) was set a priori at 5% (0.05). In order to determine the distribution of costs among patient groups, cost-concentration curves were constructed. RESULTS: A total of 5,198 patient records were analysed, representing 3,546 acne patients (2.7% of applicants to the plan). The majority of patients were female (72.2%, median age 23 years), with male patients treated at a younger age (median age 19 years). The cyproterone/oestrogen combination was found to be the most frequently prescribed agent (25.2% of script items), followed by isotretinoin (15.6%). The oral antibiotics as a group accounted for 24.9% of script items, the leading agents being minocycline (10.1%) and doxycycline (7.1%). Isotretinoin (44.1%) represented the greatest expense, followed by hormonal therapies (24.7%) and oral antibiotics (16.7%). Female isotretinoin patients (55.1%) were older (median age 25 years), while the male patients were of an equivalent age to the collective sample. Patients treated with oral antibiotics represented the youngest group of patients (median age 20 years), with 57.8% being female. The annual pharmacotherapy expense per patient on oral antibiotics was R1 971.81 compared with R2 670.20 for all patients, and R6 140.81 for the isotretinoin group. For each of these groups there was an uneven cost distribution among patients. CONCLUSION: The treatment of acne represents a significant burden to funders, estimated at R7.2 million per 100,000 beneficiaries. The distinct age and gender distribution patterns, together with the uneven distribution of costs among patients, provide valuable information for the treatment and management of the condition. This information indicates that the introduction of clinically based, focused management principles supported by sound pharmaco-economic arguments will be required to manage acne effectively.

Acne Vulgaris↗
PubMed2003

Clinical and cost-effectiveness of new and emerging technologies for early localised prostate cancer: a systematic review.

OBJECTIVES: To evaluate the clinical and cost-effectiveness of new and emerging technologies for early, localised prostate cancer. DATA SOURCES: Electronic databases, reference lists of relevant articles and various health services research-related resources. REVIEW METHODS: A list of new and emerging technologies was identified and agreed. A systematic review was undertaken and selected studies were reviewed against a set of criteria. An economic model was developed and used to compare the specified newer treatments with the traditional approaches. RESULTS: For neoadjuvant hormonal therapy, no evidence of benefit was seen in terms of biochemical disease-free survival. For adjuvant hormonal therapy, there was no evidence of benefit in terms of survival, but some conflicting evidence that higher risk patients may benefit. The largest number of studies reported results for brachytherapy, where some evidence suggested that it may be more effective than standard treatments for lower risk patients, although less effective for intermediate- and high-risk patients, in terms of biochemical disease-free survival. Lower quality evidence reported fewer complications than for standard treatments. Higher quality evidence suggested that disease-specific quality of life (QoL) for brachytherapy patients was lower than for patients receiving standard treatments. The review of three-dimensional conformal radiotherapy (3D-CRT) considered treatment-related morbidity, where significantly fewer gastrointestinal complications occurred than with standard radiotherapy. It was suggested that higher radiation doses achieved better disease control, although patient characteristics were often reported as independent indicators of control. The review of intensity-modulated conformal radiotherapy suggested that late gastrointestinal toxicity may be reduced compared with 3D-CRT. For cryotherapy, high rates of impotence were reported. Owing to the paucity and poor quality of evidence identified for other interventions, conclusions regarding their clinical effectiveness cannot be drawn. Cost-effectiveness estimates were based on the impact of adverse events on quality-adjusted life-years and the assessment was restricted to brachytherapy, 3D-CRT and cryotherapy compared with standard treatments. Of the new treatments included, only cryotherapy appeared not to be potentially cost-effective compared with traditional treatments, owing to the associated high incidence of impotence. CONCLUSIONS: The results of the clinical effectiveness review should be viewed in the context of the quality of the available evidence. Very few randomised controlled trials (RCTs) were identified, with the majority of included studies being descriptive case series, open to patient selection bias and measuring surrogate end-points with short-term follow-up. It is difficult therefore to draw conclusions on the relative benefits or otherwise of the newer technologies owing to the lack of substantive evidence of any quality and the lack of comparisons between the newer technologies and with standard treatments. Given the lack of high-quality clinical evidence with long-term follow-up and the uncertainty surrounding the assumptions in the economic analysis, the following areas are recommended for further research: RCTs with sufficient follow-up to measure benefits in terms of overall survival to include QoL measurement to establish trade-offs between potential adverse events and benefits of treatment; the identification of prognostic risk factors among men diagnosed with early prostate cancer; QoL studies to compare the utility of health states among patients on active monitoring, patients receiving treatment and the comparable healthy population; the relationship between surrogate end-points and survival; and the adoption of standard definitions for adverse events.

Cost-Benefit Analysis↗
PubMed2005

Re-evaluating the burden of rabies in Africa and Asia.

OBJECTIVE: To quantify the public health and economic burden of endemic canine rabies in Africa and Asia. METHODS: Data from these regions were applied to a set of linked epidemiological and economic models. The human population at risk from endemic canine rabies was predicted using data on dog density, and human rabies deaths were estimated using a series of probability steps to determine the likelihood of clinical rabies developing in a person after being bitten by a dog suspected of having rabies. Model outputs on mortality and morbidity associated with rabies were used to calculate an improved disability-adjusted life year (DALY) score for the disease. The total societal cost incurred by the disease is presented. FINDINGS: Human mortality from endemic canine rabies was estimated to be 55 000 deaths per year (90% confidence interval (CI) = 24 000-93 000). Deaths due to rabies are responsible for 1.74 million DALYs lost each year (90% CI = 0.75-2.93). An additional 0.04 million DALYs are lost through morbidity and mortality following side-effects of nerve-tissue vaccines. The estimated annual cost of rabies is USD 583.5 million (90% CI = USD 540.1-626.3 million). Patient-borne costs for post-exposure treatment form the bulk of expenditure, accounting for nearly half the total costs of rabies. CONCLUSION: Rabies remains an important yet neglected disease in Africa and Asia. Disparities in the affordability and accessibility of post-exposure treatment and risks of exposure to rabid dogs result in a skewed distribution of the disease burden across society, with the major impact falling on those living in poor rural communities, in particular children.

Africa↗
PubMed1997

The problem of quality of life in medicine.

The use of the term "quality of life" to encompass the values and perceptions of patients has created doubt, confusion, and misunderstanding among practitioners, researchers, policymakers, and patients. The principal reason for this state of affairs is that a clear conceptual basis for quality-of-life measures is lacking. In this article, the current rationale for quality-of-life measurement in the health field is examined, and the drawbacks of the various models being used are outlined. Our suggestion is that quality of life as an outcome could be explored more clearly (ie, defined) if quality of life were replaced with a more easily handled notion such as that of "subjective health status." However, the idea that the patient's perspective is as valid as that of the clinician when it comes to evaluating outcomes has a great deal of legitimacy and should certainly not be abandoned.

Cultural Characteristics↗
PubMedDate not supplied

Individual cigarette consumption and addiction: a flexible limited dependent variable approach.

A variety of limited dependent variable models have been used in microeconometric studies of smoking. We present a general model of the simultaneous decisions of how much to smoke and whether to quit, which allows a more flexible parameterization and distributional assumptions. The model incorporates the fixed costs associated with quitting and allows for the separate influence of addiction on participation and consumption. The model is applied to data on smoking from the 1984-85 UK Health and Lifestyle Survey, and is shown to outperform a range of nested models that have been used extensively in the empirical literature.

Cost-Benefit Analysis↗
PubMed1998

Pharmacotherapy for people with Alzheimer's disease: a Markov-cycle evaluation of five years' therapy using donepezil.

This article combines data from a clinical trial of donepezil with costing figures to evaluate expected direct costs of care over 5 years after diagnosis of Alzheimer's disease (AD) for patients aged 75 years and over at diagnosis. A Markov model simulates the progression of elderly persons through changing levels of severity. The model compares three treatment regimes for each of two patient groups; mild AD at start of treatment; moderate AD at start of treatment. Patients are followed until 5 years after the start of the treatment. Despite the acquisition costs, use of donepezil is approximately cost-neutral for both 5 mg and 10 mg treatment groups and for patients initially at either mild or moderate states of illness. Expected costs are slightly higher than for the placebo group, but higher expenditure on drugs is partly offset by lower costs of care consequent on treated patients not declining as rapidly as those untreated. The model showed that donepezil patients spent less time in the state of severe dementia, where costs of care are higher. Sensitivity analysis on key assumptions demonstrated that expected costs were highly dependent on discount rate and, more significantly, on the mortality rate.

Aged↗
PubMed2005

Eradication of Helicobacter pylori for non-ulcer dyspepsia.

BACKGROUND: Helicobacter pylori (H pylori) is the main cause of peptic ulcer disease. The role of H pylori in non-ulcer dyspepsia is less clear. OBJECTIVES: To determine the effect of H pylori eradication on dyspepsia symptoms in patients with non-ulcer dyspepsia. SEARCH STRATEGY: Trials were identified through electronic searches of the Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CINAHL and SIGLE, using appropriate subject headings and keywords, searching bibliographies of retrieved articles, and through contacts with experts in the fields of dyspepsia and with pharmaceutical companies. These searches were updated in October 2004. SELECTION CRITERIA: All parallel group randomised controlled trials (RCTs) comparing drugs to eradicate H pylori with placebo or other drugs known not to eradicate H pylori for patients with non-ulcer dyspepsia. DATA COLLECTION AND ANALYSIS: Data were collected on individual and global dyspeptic symptom scores, quality of life measures and adverse effects. Dyspepsia outcomes were dichotomised into minimal/resolved versus same/worse symptoms. MAIN RESULTS: Seventeen randomised controlled trials were included in the systematic review. Fourteen trials compared antisecretory dual or triple therapy with placebo antibiotics +/- antisecretory therapy, and evaluated dyspepsia at 3-12 months. Thirteen of these trials gave results as dichotomous outcomes evaluating 3186 patients and there was no significant heterogeneity between the studies. There was a 8% relative risk reduction in the H pylori eradication group (95% CI = 3% to 12%) compared to placebo. The number needed to treat to cure one case of dyspepsia = 18 (95% CI = 12 to 48). A further three trials compared Bismuth based H pylori eradication with an alternative pharmacological agent. These trials were smaller and had a shorter follow-up but suggested H pylori eradication was more effective than either H2 receptor antagonists or sucralfate in treating non-ulcer dyspepsia. AUTHORS' CONCLUSIONS: H pylori eradication therapy has a small but statistically significant effect in H pylori positive non-ulcer dyspepsia. An economic model suggests this modest benefit may still be cost-effective but more research is needed.

Adult↗