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Principle Findings (principle + finding)
Selected AbstractsThe Impact of CHIP on Children's Insurance Coverage: An Analysis Using the National Survey of America's FamiliesHEALTH SERVICES RESEARCH, Issue 6 2009Lisa Dubay Objective. To assess the impact of the Children's Health Insurance Program (CHIP) on the distribution of health insurance coverage for low-income children. Data Source. The primary data for the study were from the 1997, 1999, and 2002 National Survey of America's Families (NSAF), which includes a total sample of 62,497 children across all 3 years, supplemented with data from other data sources. Study Design. The study uses quasi-experimental designs and tests the sensitivity of the results to using instrumental variable and difference-in-difference approaches. A detailed Medicaid and CHIP eligibility model was developed for this study. Balanced repeated replicate weights were used to account for the complex sample of the NSAF. Descriptive and multivariate analyses were conducted. Principle Findings. The results varied depending on the approach utilized but indicated that the CHIP program led to significant increases in public coverage (14,20 percentage points); and declines in employer-sponsored coverage (6,7 percentage points) and in uninsurance (7,12 percentage points). The estimated share of CHIP enrollment attributable to crowd-out ranged from 33 to 44 percent. Smaller crowd-out effects were found for Medicaid-eligible children. Conclusions. Implementation of the CHIP program resulted in large increases in public coverage with estimates of crowd-out consistent with initial projections made by the Congressional Budget Office. This paper demonstrates that public health insurance expansions can lead to substantial reductions in uninsurance without causing a large-scale erosion of employer coverage. [source] Development and Validation of a Risk-Adjustment Tool in Acute AsthmaHEALTH SERVICES RESEARCH, Issue 5p1 2009Chu-Lin Tsai Objective. To develop and prospectively validate a risk-adjustment tool in acute asthma. Data Sources. Data were obtained from two large studies on acute asthma, the Multicenter Airway Research Collaboration (MARC) and the National Emergency Department Safety Study (NEDSS) cohorts. Both studies involved >60 emergency departments (EDs) and were performed during 1996,2001 and 2003,2006, respectively. Both included patients aged 18,54 years presenting to the ED with acute asthma. Study Design. Retrospective cohort studies. Data Collection. Clinical information was obtained from medical record review. The risk index was derived in the MARC cohort and then was prospectively validated in the NEDSS cohort. Principle Findings. There were 3,515 patients in the derivation cohort and 3,986 in the validation cohort. The risk index included nine variables (age, sex, current smoker, ever admitted for asthma, ever intubated for asthma, duration of symptoms, respiratory rate, peak expiratory flow, and number of beta-agonist treatments) and showed satisfactory discrimination (area under the receiver operating characteristic curve, 0.75) and calibration ( p=.30 for Hosmer,Lemeshow test) when applied to the validation cohort. Conclusions. We developed and validated a novel risk-adjustment tool in acute asthma. This tool can be used for health care provider profiling to identify outliers for quality improvement purposes. [source] Managed Care Quality of Care and Plan Choice in New York SCHIPHEALTH SERVICES RESEARCH, Issue 3 2009Hangsheng Liu Objective. To examine whether low-income parents of children enrolled in the New York State Children's Health Insurance Program (SCHIP) choose managed care plans with better quality of care. Data Sources. 2001 New York SCHIP evaluation data; 2001 New York State Managed Care Plan Performance Report; 2000 New York State Managed Care Enrollment Report. Study Design. Each market was defined as a county. A final sample of 2,325 new enrollees was analyzed after excluding those in markets with only one SCHIP plan. Plan quality was measured using seven Consumer Assessment of Health Plans Survey (CAHPS) and three Health Plan Employer Data and Information Set (HEDIS) scores. A conditional logit model was applied with plan and individual/family characteristics as covariates. Principle Findings. There were 30 plans in the 45 defined markets. The choice probability increased 2.5 percentage points for each unit increase in the average CAHPS score, and the association was significantly larger in children with special health care needs. However, HEDIS did not show any statistically significant association with plan choice. Conclusions. Low-income parents do choose managed care plans with higher CAHPS scores for their newly enrolled children, suggesting that overall quality could improve over time because of the dynamics of enrollment. [source] The Relationship between Hospital Volume and Mortality in Mechanical Ventilation: An Instrumental Variable AnalysisHEALTH SERVICES RESEARCH, Issue 3 2009Jeremy M. Kahn Objective. To examine the relationship between hospital volume and mortality for nonsurgical patients receiving mechanical ventilation. Data Sources. Pennsylvania state discharge records from July 1, 2004, to June 30, 2006, linked to the Pennsylvania Department of Health death records and the 2000 United States Census. Study Design. We categorized all general acute care hospitals in Pennsylvania (n=169) by the annual number of nonsurgical, mechanically ventilated discharges according to previous criteria. To estimate the relationship between annual volume and 30-day mortality, we fit linear probability models using administrative risk adjustment, clinical risk adjustment, and an instrumental variable approach. Principle Findings. Using a clinical measure of risk adjustment, we observed a significant reduction in the probability of 30-day mortality at higher volume hospitals (,300 admissions per year) compared with lower volume hospitals (<300 patients per year; absolute risk reduction: 3.4%, p=.04). No significant volume,outcome relationship was observed using only administrative risk adjustment. Using the distance from the patient's home to the nearest higher volume hospital as an instrument, the volume,outcome relationship was greater than observed using clinical risk adjustment (absolute risk reduction: 7.0%, p=.01). Conclusions. Care in higher volume hospitals is independently associated with a reduction in mortality for patients receiving mechanical ventilation. Adequate risk adjustment is essential in order to obtained unbiased estimates of the volume,outcome relationship. [source] Effect of an Expenditure Cap on Low-Income Seniors' Drug Use and Spending in a State Pharmacy Assistance ProgramHEALTH SERVICES RESEARCH, Issue 3 2009Christine E. Bishop Objective. To estimate the impact of a soft cap (a ceiling on utilization beyond which insured enrollees pay a higher copayment) on low-income elders' use of prescription drugs. Data Sources and Setting. Claims and enrollment files for the first year ( June 2002 through May 2003) of the Illinois SeniorCare program, a state pharmacy assistance program, and Medicare claims and enrollment files, 2001 through 2003. SeniorCare enrolled non-Medicaid-eligible elders with income less than 200 percent of Federal Poverty Level. Minimal copays increased by 20 percent of prescription cost when enrollee expenditures reached $1,750. Research Design. Models were estimated for three dependent variables: enrollees' average monthly utilization (number of prescriptions), spending, and the proportion of drugs that were generic rather than brand. Observations included all program enrollees who exceeded the cap and covered two periods, before and after the cap was exceeded. Principle Findings. On average, enrollees exceeding the cap reduced the number of drugs they purchased by 14 percent, monthly expenditures decreased by 19 percent, and the proportion generic increased by 4 percent, all significant at p<.01. Impacts were greater for enrollees with greater initial spending, for enrollees without one of five chronic illness diagnoses in the previous calendar year, and for enrollees with lower income. Conclusions. Near-poor elders enrolled in plans with caps or coverage gaps, including Part D plans, may face sharp declines in utilization when they exceed these thresholds. [source] Power of Tests for a Dichotomous Independent Variable Measured with ErrorHEALTH SERVICES RESEARCH, Issue 3 2008Daniel F. McCaffrey Objective. To examine the implications for statistical power of using predicted probabilities for a dichotomous independent variable, rather than the actual variable. Data Sources/Study Setting. An application uses 271,479 observations from the 2000 to 2002 CAHPS Medicare Fee-for-Service surveys. Study Design and Data. A methodological study with simulation results and a substantive application to previously collected data. Principle Findings. Researchers often must employ key dichotomous predictors that are unobserved but for which predictions exist. We consider three approaches to such data: the classification estimator (1); the direct substitution estimator (2); the partial information maximum likelihood estimator (3, PIMLE). The efficiency of (1) (its power relative to testing with the true variable) roughly scales with the square of one less the classification error. The efficiency of (2) roughly scales with the R2 for predicting the unobserved dichotomous variable, and is usually more powerful than (1). Approach (3) is most powerful, but for testing differences in means of 0.2,0.5 standard deviations, (2) is typically more than 95 percent as efficient as (3). Conclusions. The information loss from not observing actual values of dichotomous predictors can be quite large. Direct substitution is easy to implement and interpret and nearly as efficient as the PIMLE. [source] Qualitative Data Analysis for Health Services Research: Developing Taxonomy, Themes, and TheoryHEALTH SERVICES RESEARCH, Issue 4 2007Elizabeth H. Bradley Objective. To provide practical strategies for conducting and evaluating analyses of qualitative data applicable for health services researchers. Data Sources and Design. We draw on extant qualitative methodological literature to describe practical approaches to qualitative data analysis. Approaches to data analysis vary by discipline and analytic tradition; however, we focus on qualitative data analysis that has as a goal the generation of taxonomy, themes, and theory germane to health services research. Principle Findings. We describe an approach to qualitative data analysis that applies the principles of inductive reasoning while also employing predetermined code types to guide data analysis and interpretation. These code types (conceptual, relationship, perspective, participant characteristics, and setting codes) define a structure that is appropriate for generation of taxonomy, themes, and theory. Conceptual codes and subcodes facilitate the development of taxonomies. Relationship and perspective codes facilitate the development of themes and theory. Intersectional analyses with data coded for participant characteristics and setting codes can facilitate comparative analyses. Conclusions. Qualitative inquiry can improve the description and explanation of complex, real-world phenomena pertinent to health services research. Greater understanding of the processes of qualitative data analysis can be helpful for health services researchers as they use these methods themselves or collaborate with qualitative researchers from a wide range of disciplines. [source] Case-Mix Adjustment of the CAHPS® Hospital SurveyHEALTH SERVICES RESEARCH, Issue 6p2 2005A. James O'Malley Objectives: To develop a model for case-mix adjustment of Consumer Assessment of Healthcare Providers and Systems (CAHPS®) Hospital survey responses, and to assess the impact of adjustment on comparisons of hospital quality. Data Sources: Survey of 19,720 patients discharged from 132 hospitals. Methods: We analyzed CAHPS Hospital survey data to assess the extent to which patient characteristics predict patient ratings ("predictive power") and the heterogeneity of the characteristics across hospitals. We combined the measures to estimate the impact of each predictor ("impact factor") and selected high impact variables for adjusting ratings from the CAHPS Hospital survey. Principle Findings: The most important case-mix variables are: hospital service (surgery, obstetric, medical), age, race (non-Hispanic black), education, general health status (GHS), speaking Spanish at home, having a circulatory disorder, and interactions of each of these variables with service. Adjustment for GHS and education affected scores in each of the three services, while age and being non-Hispanic black had important impacts for those receiving surgery or medical services. Circulatory disorder, Spanish language, and Hispanic affected scores for those treated on surgery, obstetrics, and medical services, respectively. Of the 20 medical conditions we tested, only circulatory problems had an important impact within any of the services. Results were consistent for the overall ratings of nurse, doctor, and hospital. Although the overall impact of case-mix adjustment is modest, the rankings of some hospitals may be substantially affected. Conclusions: Case-mix adjustment has a small impact on hospital ratings, but can lead to important reductions in the bias in comparisons between hospitals. [source] A critical evaluation of the brain efflux index method as applied to the nitric oxide synthase inhibitor, aminoguanidineBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 9 2001Joseph J. Raybon Abstract The Brain Efflux Index (BEI) method is an in vivo procedure designed to quantitate saturable efflux mechanisms resident at the blood,brain barrier (BBB). The present work utilized the BEI method to assess the BBB efflux mechanisms of [14C]aminoguanidine, a nitric oxide synthase inhibitor. The BEI for [14C]aminoguanidine was >100% (relative to [3H]inulin diffusion) over a range of 41,184 pmol after 40 min. The unusually high retention (>100%) of [14C]aminoguanidine suggested brain parenchymal sequestration, either by neuronal uptake or tissue protein binding. The uptake of [14C]aminoguanidine in dendritic neuronal endings (synaptosomes) showed a saturable concentration dependency, consistent with a carrier-mediated process. Nonlinear least-squares regression yielded the following Michaelis,Menten and diffusional (kns) parameters for synaptosomal [14C]aminoguanidine uptake: Vmax=118.50± 28.77 pmol x mg protein,1/3 min; Km=58.34±8.33 ,M; kns=0.15±0.029 pmol x mg protein,1/3 min/,M; mean±SEM; n=3 concentration profiles). Protein binding studies using brain tissue showed negligible binding. In summary, this work identified three principle findings: (1) An apparent lack of quantifiable aminoguanidine BBB efflux; (2) a previously undescribed synaptosomal accumulation process for aminoguanidine; and (3) an interesting limitation of the BEI technique where unusual brain parenchymal sequestration yields values >100%. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||