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Score Methods (score + methods)
Kinds of Score Methods Selected AbstractsThe Effect of Three-Tier Formulary Adoption on Medication Continuation and Spending among Elderly RetireesHEALTH SERVICES RESEARCH, Issue 5 2007Haiden A. Huskamp Objective. To assess the effect of three-tier formulary adoption on medication continuation and spending among elderly members of retiree health plans. Data Sources. Pharmacy claims and enrollment data on elderly members of four retiree plans that adopted a three-tier formulary over the period July 1999 through December 2002 and two comparison plans that maintained a two-tier formulary during this period. Study Design. We used a quasi-experimental design to compare the experience of enrollees in intervention and comparison plans. We used propensity score methods to match intervention and comparison users of each drug class and plan. We estimated repeated measures regression models for each class/plan combination for medication continuation and monthly plan, enrollee, and total spending. We estimated logit models of the probability of nonpersistent use, medication discontinuation, and medication changes. Data Collection/Extraction Methods. We used pharmacy claims to create person-level drug utilization and spending files for the year before and year after three-tier adoption. Principal Findings. Three-tier formulary adoption resulted in shifting of costs from plan to enrollee, with relatively small effects on medication continuation. Although implementation had little effect on continuation on average, a small minority of patients were more likely to have gaps in use and discontinue use relative to comparison patients. Conclusions. Moderate cost sharing increases from three-tier formulary adoption had little effect on medication continuation among elderly enrolled in retiree health plans with relatively generous drug coverage. [source] The Effect of Medicaid Payment Generosity on Access and Use among BeneficiariesHEALTH SERVICES RESEARCH, Issue 3 2005Yu-Chu Shen Objective. This study examines the effects of Medicaid payment generosity on access and care for adult and child Medicaid beneficiaries. Data Source. Three years of the National Surveys of America's Families (1997, 1999, 2002) are linked to the Urban Institute Medicaid capitation rate surveys, the Area Resource File, and the American Hospital Association survey files. Study Design. In order to identify the effect of payment generosity apart from unmeasured differences across areas, we compare the experiences of Medicaid beneficiaries with groups that should not be affected by Medicaid payment policies. To assure that these groups are comparable to Medicaid beneficiaries, we reweight the data using propensity score methods. We use a difference-in-differences model to assess the effects of Medicaid payment generosity on four categories of access and use measures (continuity of care, preventive care, visits, and perceptions of provider communication and quality of care). Principal Findings. Higher payments increase the probability of having a usual source of care and the probability of having at least one visit to a doctor and other health professional for Medicaid adults, and produce more positive assessments of the health care received by adults and children. However, payment generosity has no effect on the other measures that we examined, such as the probability of receiving preventive care or the probability of having unmet needs. Conclusions. Higher payment rates can improve some aspects of access and use for Medicaid beneficiaries, but the effects are not dramatic. [source] How close is close enough?JOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 3 2007Evaluating propensity score matching using data from a class size reduction experiment In recent years, propensity score matching (PSM) has gained attention as a potential method for estimating the impact of public policy programs in the absence of experimental evaluations. In this study, we evaluate the usefulness of PSM for estimating the impact of a program change in an educational context (Tennessee's Student Teacher Achievement Ratio Project [Project STAR]). Because Tennessee's Project STAR experiment involved an effective random assignment procedure, the experimental results from this policy intervention can be used as a benchmark, to which we compare the impact estimates produced using propensity score matching methods. We use several different methods to assess these nonexperimental estimates of the impact of the program. We try to determine "how close is close enough," putting greatest emphasis on the question: Would the nonexperimental estimate have led to the wrong decision when compared to the experimental estimate of the program? We find that propensity score methods perform poorly with respect to measuring the impact of a reduction in class size on achievement test scores. We conclude that further research is needed before policymakers rely on PSM as an evaluation tool. © 2007 by the Association for Public Policy Analysis and Management [source] Principles for modeling propensity scores in medical research: a systematic literature review,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 12 2004Sherry Weitzen PhD Abstract Purpose To document which established criteria for logistic regression modeling researchers consider when using propensity scores in observational studies. Methods We performed a systematic review searching Medline and Science Citation to identify observational studies published in 2001 that addressed clinical questions using propensity score methods to adjust for treatment assignment. We abstracted aspects of propensity score model development (e.g. variable selection criteria, continuous variables included in correct functional form, interaction inclusion criteria), model discrimination and goodness of fit for 47 studies meeting inclusion criteria. Results We found few studies reporting on the propensity score model development or evaluation of model fit. Conclusions Reporting of aspects related to propensity score model development is limited and raises questions about the value of these principles in developing propensity scores from which unbiased treatment effects are estimated. Copyright © 2004 John Wiley & Sons, Ltd. [source] Sample Size Determination for Establishing Equivalence/Noninferiority via Ratio of Two Proportions in Matched,Pair DesignBIOMETRICS, Issue 4 2002Man-Lai Tang Summary. In this article, we propose approximate sample size formulas for establishing equivalence or noninferiority of two treatments in match-pairs design. Using the ratio of two proportions as the equivalence measure, we derive sample size formulas based on a score statistic for two types of analyses: hypothesis testing and confidence interval estimation. Depending on the purpose of a study, these formulas can be used to provide a sample size estimate that guarantees a prespecified power of a hypothesis test at a certain significance level or controls the width of a confidence interval with a certain confidence level. Our empirical results confirm that these score methods are reliable in terms of true size, coverage probability, and skewness. A liver scan detection study is used to illustrate the proposed methods. [source] End-of-life care for older cancer patients in the Veterans Health Administration versus the private sector,,§¶CANCER, Issue 15 2010Nancy L. Keating MD Abstract BACKGROUND: Treatment of older cancer patients at the end of life has become increasingly aggressive, despite the absence of evidence for better outcomes. We compared aggressiveness of end-of-life care of older metastatic cancer patients treated in the Veterans Health Administration (VHA) and those under fee-for-service Medicare arrangements. METHODS: Using propensity score methods, we matched 2913 male veterans who were diagnosed with stage IV lung or colorectal cancer in 2001-2002 and died before 2006 with 2913 similar men enrolled in fee-for-service Medicare living in Surveillance, Epidemiology, and End Result (SEER) areas. We assessed chemotherapy within 14 days of death, intensive care unit (ICU) admissions within 30 days of death, and >1 emergency room visit within 30 days of death. RESULTS: Among matched cohorts, men treated in the VHA were less likely than men in the private sector to receive chemotherapy within 14 days of death (4.6% vs 7.5%, P < .001), be admitted to an ICU within 30 days of death (12.5% vs 19.7%, P < .001), or have >1 emergency room visit within 30 days of death (13.1 vs 14.7, P = .09). CONCLUSIONS: Older men with metastatic lung or colorectal cancer treated in the VHA healthcare system received less aggressive end-of-life care than similar men in fee-for-service Medicare. This may result from the absence of financial incentives for more intensive care in the VHA or because this integrated delivery system is better structured to limit potentially overly aggressive care. Additional studies are needed to assess whether men undergoing less aggressive end-of-life care also experience better outcomes. Cancer 2010. © 2010 American Cancer Society. [source] |