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M C Weinstein

Publications and source records attributed to M C Weinstein.

At least 91 records · Page 5Linked to original sources
PubMed1991

Cost-effectiveness of hormone replacement therapy after the menopause.

The net resource costs and net health benefits of treating perimenopausal women with hormone replacement therapy were evaluated within the framework of cost-effectiveness analysis. Data from the epidemiological literature were used to estimate changes in discounted life expectancy from hip fracture, ischaemic heart disease and breast cancer that are associated with hormone replacement therapy under a variety of assumptions. Economic data were used to estimate changes in total discounted costs that result from the use of hormone replacement therapy. For women with a previous hysterectomy, 10- and 15-year courses of unopposed oestrogen were evaluated. The baseline assumptions for unopposed oestrogen were that breast cancer incidence would be increased for current users by 36% and that deaths from ischaemic heart disease would be reduced by 50% relative to non-users. Under these assumptions, oestrogen replacement therapy was found to be cost-effective, with ratios ranging from $9130 to $12,620 per additional year of life saved. For women who have not had a hysterectomy, 10- and 15-year courses of oestrogen combined with progestin were evaluated. The baseline assumptions for combined therapy were that breast cancer incidence and ischaemic heart disease deaths were unaffected. Under these assumptions, combined therapy was more costly, with ratios ranging from $86,100 to $88,500. Unless combined therapy is found to confer protection against ischaemic heart disease, the most cost-effective strategies for women with no prior hysterectomy may involve screening perimenopausal women to detect women at highest risk of hip fracture followed by selective treatment.

Adult↗
PubMed1991

Cost-effectiveness of hepatitis-B vaccine in Greece. A country of intermediate HBV endemicity.

We evaluated the cost-effectiveness of (a) a vaccination program for the prevention of hepatitis B; and (b) the two commercially available vaccines (Merck Sharp and Dohme; Pasteur Institute) in Greece, a country of intermediate endemicity. We examined cases of hepatitis-B infection prevented and the expected medical costs among the high-risk groups of medical and nursing students, hospital personnel, and the general population. Employing a vaccination program reduces considerably the risk of infection, especially in the high-risk groups, while it increases the total cost. The vaccines are very comparable in terms of both health and economic outcomes. Sensitivity analysis indicated that vaccine cost, incidence of hepatitis B, and compliance were the key factors for the choice of (a) whether to undertake an extensive program to prevent hepatitis-B infection and its chronic sequelae; and (b) which vaccine to administer.

Adult↗
PubMed1991

Performance of a five-item mental health screening test.

We compared the screening accuracy of a short, five-item version of the Mental Health Inventory (MHI-5) with that of the 18-item MHI, the 30-item version of the General Health Questionnaire (GHQ-30), and a 28-item Somatic Symptom Inventory (SSI-28). Subjects were newly enrolled members of a health maintenance organization (HMO), and the criterion diagnoses were those found through use of the Diagnostic Interview Schedule (DIS) in a stratified sample of respondents to an initial, mailed GHQ. To compare questionnaires, we used receiver operating characteristic analysis, comparing areas under curves through the method of Hanley and McNeil. The MHI-5 was as good as the MHI-18 and the GHQ-30, and better than the SSI-28, for detecting most significant DIS disorders, including major depression, affective disorders generally, and anxiety disorders. Areas under curve for the MHI-5 ranged from 0.739 (for anxiety disorders) to 0.892 (for major depression). Single items from the MHI also performed well. In this population, short screening questionnaires, and even single items, may detect the majority of people with DIS disorders while incurring acceptably low false-positive rates. Perhaps such extremely short questionnaires could more commonly reach use in actual practice than the longer versions have so far, permitting earlier assessment and more appropriate treatment of psychiatrically troubled patients in primary care settings.

Adult↗
PubMed1991

Expected gains in life expectancy from various coronary heart disease risk factor modifications.

BACKGROUND: Despite much evidence that modifying risk factors for coronary heart disease can decrease morbidity and mortality, little is known about the impact of risk-factor modification on life expectancy. METHODS AND RESULTS: We used the Coronary Heart Disease Policy Model, a state-transition computer simulation of the US population, to forecast potential gains in life expectancy from risk-factor modification for the cohort of Americans turning age 35 in 1990. Among 35-year-old men, we projected that the population-wide increase in life expectancy would be about 1.1 years from strict blood pressure control, 0.8 years from smoking cessation, 0.7 years from reduction of serum cholesterol to 200 mg/dl, and about 0.6 years from weight loss to ideal body weight. For women, reducing cholesterol to 200 mg/dl would have the greatest estimated impact-a gain of 0.8 years-whereas smoking cessation, blood pressure control, or weight loss would yield population-wide gains of 0.7, 0.4, and 0.4 years, respectively. Gains for 35-year-old individuals having a given risk factor are greater. We estimate that, on average, male smokers would gain 2.3 years from quitting smoking; males with hypertension would gain 1.1-5.3 years from reducing their diastolic blood pressure to 88 mm Hg; men with serum cholesterol levels exceeding 200 mg/dl would gain 0.5-4.2 years from lowering their serum cholesterol level to 200 mg/dl; and overweight men would gain an average of 0.7-1.7 years from achieving ideal body weight. Corresponding projected gains for at-risk women are 2.8 years from quitting smoking, 0.9-5.7 years from lowering blood pressure, 0.4-6.3 years from decreasing serum cholesterol, and 0.5-1.1 years from losing weight. Eliminating coronary heart disease mortality is estimated to extend the average life expectancy of a 35-year-old man by 3.1 years and a 35-year-old woman by 3.3 years. CONCLUSIONS: Population-wide gains in life expectancy from single risk-factor modifications are modest, but gains to individuals at risk can be more substantial.

Adult↗
PubMed1991

Bleach programs for preventing AIDS among i.v. drug users: modeling the impact of HIV prevalence.

BACKGROUND: The growing importance of drug use as a mode of HIV transmission has led to increased attention to AIDS prevention among intravenous drug users (IVDUs). This analysis examines the effectiveness of bleach distribution, a program to prevent HIV transmission via shared needles. METHODS: We used a Markov model to assess the role of the initial HIV prevalence among drug users in determining the effectiveness of bleach programs. The model incorporates survey data on risk behaviors and published information describing HIV incubation and mortality. It predicts life expectancy for cohorts of IVDUs with and without a bleach program to estimate program effectiveness. RESULTS: We found that bleach programs can produce the greatest life-year savings in areas of low HIV prevalence. In the lowest prevalence scenario (0.02 initial prevalence), initiation of the program resulted in a projected savings of 2.3 life years per HIV-negative drug user, compared with 1.7 and 1.3 years under medium (0.25) and high (0.60) prevalence, respectively. CONCLUSIONS: While bleach programs are beneficial in all groups of IVDUs, these results highlight the advantages of introducing bleach programs early, when prevalence is still comparatively low in a drug-user population.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Cost effectiveness of screening perimenopausal white women for osteoporosis: bone densitometry and hormone replacement therapy.

Bone mass measurement at menopause to identify and selectively prescribe hormone replacement therapy for women at high risk for fractures has seen limited clinical use. We used epidemiologic, clinical, and economic data in a decision-analytic model to compare the following clinical strategies for perimenopausal, asymptomatic, white women with intact uteri: no intervention; bone mineral density measurement followed by selective, long-term (15-year) estrogen-progestin therapy in women with low bone mass; and unselective, universal hormone replacement therapy. Life expectancy and direct medical cost per patient were estimated for each strategy. Strategies for screening and treating women with perimenopausal bone mineral density less than 0.9 g/cm2 or less than 1.0 g/cm2 would cost $11,700 or $22,100, respectively, per year of additional life gained. If the cost of screening is less than $84, then resource savings from hip fractures prevented would be more than the cost of screening and treatment. Universal treatment without screening would prevent additional fatal fractures but would expose many more women to the adverse effects of hormone replacement therapy and would cost an additional $349,000 per year of life gained compared with the screening strategies. When quality of life was considered, screening was found to be cost effective over a wide range of assumptions. The choice between universal treatment and screening depends on the risks (breast cancer), perceived side effects (menstrual bleeding), and benefits (prevention of ischemic heart disease) of estrogen-progestin therapy. We conclude that screening asymptomatic, perimenopausal white women to detect low bone mass and to target hormone replacement therapy at women who are at the greatest risk for fracture is a reasonably cost-effective use of health care resources. However, cost-effective screening guidelines cannot be explicitly established until further data addressing the association between bone mass measurements in the hip and hip fracture risk are available.

Aged↗
PubMed1990

Long-term cost-effectiveness of various initial monotherapies for mild to moderate hypertension.

To evaluate the comparative efficacy and cost-effectiveness of various antihypertensive medications in persons aged 35 through 64 years with diastolic blood pressure of 95 mm Hg or greater and no known coronary heart disease, we used the Coronary Heart Disease Policy Model, which is a computer simulation of overall mortality as well as the mortality, morbidity, and cost of coronary heart disease in the US population. From the pooled literature, we estimated the antihypertensive and total cholesterol effects of various antihypertensive regimens. For 20 years of simulated therapy from 1990 through 2010, the cost per year of life saved was projected to be $10,900 for propranolol hydrochloride; $16,400 for hydrochlorothiazide; $31,600 for nifedipine; $61,900 for prazosin hydrochloride; and $72,100 for captopril. Doubling the cholesterol effects of the agents under study did not significantly change their effectiveness because, in general, lowering diastolic blood pressure by 1 mm Hg was equivalent to lowering the cholesterol level by 6%. Although any projection requires multiple estimates, each of which may be open to debate, propranolol appears to be the preferred initial option under most of a variety of alternative assumptions.

Adult↗
PubMed1990

Cost-effectiveness study of the extracorporeal shock-wave lithotriptor.

We performed a cost-effectiveness analysis to examine the relative efficacy and costs of percutaneous ultrasonic lithotripsy (PUL), extracorporeal shock-wave lithotripsy (ESWL), and surgery for the treatment of upper urinary tract stones. We developed a Markov model with 35 states, cycles of 3 months, and a time frame of 5 years. Probability estimates were derived from a meta-analysis of the published literature. For stones less than or equal to 2 cm, ESWL is preferred to PUL, since it prevents 2 additional days of morbidity and saves $440. For larger stones, PUL is preferable to ESWL, avoiding 4 days of morbidity, and saving $722. Both ESWL and PUL were superior to surgery. Sensitivity analysis showed that the results are sensitive to ESWL efficacy rates, the stone recurrence rate, and the hospital component of the ESWL cost. Our analysis suggests that although ESWL is preferable, relatively small changes in the efficacy and cost can shift the preferred strategy; in addition, these findings underscore the need for more reliable data.

Cost-Benefit Analysis↗
PubMed1990

Principles of cost-effective resource allocation in health care organizations.

Cost-effectiveness analysis (CEA) is a method of economic evaluation that can be used to assess the efficiency with which health care technologies use limited resources to produce health outputs. However, inconsistencies in the way that such ratios are constructed often lead to misleading conclusions when CEAs are compared. Some of these inconsistencies, such as failure to discount or to calculate incremental ratios correctly, reflect analytical errors that, if corrected, would resolve the inconsistencies. Others reflect fundamental differences in the viewpoint of the analysis. The perspectives of different decision-making entities can properly lead to different items in the numerator and denominator of the cost-effectiveness (C/E) ratio. Producers and consumers of CEA need to be more conscious of the perspectives of analysis, so that C/E comparisons from a given perspective are based upon a common understanding of the elements that are properly included.

Cost-Benefit Analysis↗
PubMed1990

Long-term impact of smoking cessation on the incidence of coronary heart disease.

Using a simulation model of the US male population, we estimated the long-term impact that future smoking cessation programs would have on the distribution and occurrence of coronary heart disease in males ages 35-84. For interventions that reduce the number of smokers by 25 percent in 1990, the number of men free of coronary heart disease is projected to increase by 416,787 (0.7 percent) in 2015, and the age-standardized absolute incidence to decline by 2.3 percent. Incidence rates and absolute incidences are projected to fall in men under age 65, but absolute incidence would rise in men over age 65, in large part because of the increased number of men who were at risk for coronary heart disease because of a reduction in non-coronary smoking-related mortality. These trends were more marked for greater smoking reductions and were generally unaffected in a variety of analyses using alternative assumptions, which considered smoking as a risk factor in the elderly, a lag-time before benefits from smoking cessation were realized and secular declines in smoking prevalence. Subject to the assumptions of our model, we conclude that smoking reductions will markedly reduce coronary heart disease, especially in younger age groups, and that this benefit will be slightly offset by a small increase in absolute incidence in elderly men.

Adult↗
PubMed1989

Methodologic issues in policy modeling for cardiovascular disease.

Clinical decision models are intended to guide the choices of individual clinicians; policy models are intended to guide the choices of persons and organizations that affect the aggregate allocations of resources to health care problems. Although it is difficult to identify any single policymaker in the United States who can alter the aggregate effect of the millions (or billions) of individual clinical decisions, there are many potential users of policy models: payers, providers, state and local health departments, the National Institutes of Health, professional organizations, hospitals and producers of medical devices, among others. Policy models deal with populations of individuals, may be static or dynamic and may be descriptive or prescriptive. Two types of policy models that have been applied to cardiovascular disease with a focus on coronary artery bypass surgery are discussed: 1) economic evaluation models, specifically cost-effectiveness, cost utility and cost-benefit analyses; and 2) population simulation models. Cost-effectiveness models are preferable for reasons that are discussed.

Adult↗
PubMed1989

A comparison of three psychiatric screening tests using receiver operating characteristic (ROC) analysis.

Self-administered screening questionnaires are available to assist primary care physicians in detecting undiagnosed depression and anxiety disorders. This study used receiver operating characteristic (ROC) analysis to evaluate three such tests: the General Health Questionnaire (GHQ), the Mental Health Inventory (MHI), and the Somatic Symptom Inventory (SSI). Stratified by the results of a preliminary GHQ, 364 health maintenance organization (HMO) members were given these tests and a Diagnostic Interview Schedule (DIS), the latter used as a "truth" standard for current psychiatric diagnosis. The MHI performed significantly better than the GHQ in detecting mental disorders generally and anxiety disorders in particular, and somewhat better in detecting affective disorders. The SSI performed best in detecting anxiety disorders and was significantly better than the GHQ. When subjects who had participated in a previous study involving repeated GHQ administration were excluded, sensitivity of all tests improved, especially the GHQ. We conclude that the MHI can be a useful tool for screening primary care patients, and that the SSI has additional predictive value with respect to anxiety disorders.

Adult↗
PubMed1989

Relative impact of targeted versus populationwide cholesterol interventions on the incidence of coronary heart disease. Projections of the Coronary Heart Disease Policy Model.

We used the Coronary Heart Disease Policy Model, a state-transition computer simulation, to assess the absolute and relative effects of two different national cholesterol interventions: a targeted program to identify and treat all individuals with elevated serum cholesterol levels (greater than or equal to 250 mg/dl) versus a populationwide program to reduce everyone's serum cholesterol level. Based on the assumptions inherent in our model, which uses the Framingham Heart Study coefficients, we estimate the targeted program would reduce projected coronary heart disease absolute incidence by 8-10% in men ages 35-54 years and by 1-4% in men ages 55-74 years. Our model suggests that similar reductions in coronary heart disease incidence could be achieved by a 10 mg/dl populationwide reduction in serum cholesterol levels. In women, the targeted program would yield greater relative and absolute benefits and would be equivalent to a approximately 23 mg/dl populationwide reduction in serum cholesterol. We conclude that it would be inadvisable to rely solely on targeted cholesterol reduction programs to reduce national coronary heart disease.

Adult↗
PubMed1989

Issues in the economic evaluation of community water fluoridation.

Community water fluoridation has long been recognized as an effective public health intervention in the prevention of dental caries. The recently documented secular decline in dental caries, however, presents for policy makers the challenge of appropriately allocating limited health care resources between a variety of health care programs. Appropriate economic assessment of these alternatives becomes critical for rational distribution of such resources. Cost-benefit and cost-effectiveness analyses are techniques that, when used correctly, can guide policy makers facing such decisions. This paper reviews and critiques the published literature assessing the cost effectiveness and cost benefit of community water fluoridation using criteria developed for economic evaluation. Eight papers met the criteria for inclusion in the present study. In general, the articles failed to incorporate the declining prevalence of dental caries into their analyses and to fully document costs associated with water fluoridation. Treatment savings from dental care averted secondary to water fluoridation were not appropriately incorporated into the cost-effectiveness analyses, thereby overestimating the marginal cost associated with fluoridation. Specification of outcome measures to assess the consequences of water fluoridation failed to incorporate the dynamic nature of dental disease. Suggestions for improving the generalizability and usefulness of future cost-benefit and cost-effectiveness analyses are made.

Bias↗