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Michael E. Chernew - One of the best experts on this subject based on the ideXlab platform.
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Changes in Health Care Use Associated With the Introduction of Hospital Global Budgets in Maryland
JAMA internal medicine, 2018Co-Authors: Eric T. Roberts, Michael E. Chernew, J. Michael Mcwilliams, Laura A. Hatfield, Sule Gerovich, Lauren Gilstrap, Ateev MehrotraAbstract:Importance In 2014, the State of Maryland placed the majority of its hospitals under all-payer Global Budgets for inpatient, hospital outpatient, and emergency department care. Goals of the program included reducing unnecessary hospital utilization and encouraging greater use of primary care. Objective To compare changes in hospital and primary care use through the first 2 years of Maryland’s hospital Global budget program among fee-for-service Medicare beneficiaries in Maryland vs matched control areas. Design, Setting, and Participants We matched 8 Maryland counties (94 967 beneficiaries) with hospitals in the program to 27 non-Maryland control counties (206 389 beneficiaries). Using difference-in-differences analysis, we compared changes in hospital and primary care use in Maryland vs the control counties from before (2009-2013) to after (2014-2015) the payment change, using 2 different assumptions. First, we assumed that preintervention differences between Maryland and the control counties would have remained constant past 2014 had Maryland not implemented Global Budgets (parallel trend assumption). Second, we assumed that differences in preintervention trends would have continued without the payment change (differential trend assumption). Main Outcomes and Measures Hospital stays (defined as admissions and observation stays); return hospital stays within 30 days of a prior hospital stay; emergency department visits that did not result in admission; price-standardized hospital outpatient department (HOPD) utilization; and visits with primary care physicians (overall and within 7 days of a hospital stay). Results We matched 8 Maryland counties with hospitals in the program (94 967 beneficiaries; 41.8% male; mean [SD] age, 72.3 [12.2] years) to 27 non-Maryland control counties (206 389 beneficiaries; 42.8% male; mean [SD] age, 71.7 [12.5] years). Assuming parallel trends, we estimated a differential change in Maryland of −0.47 annual hospital stays per 100 beneficiaries (95% CI, −1.65 to 0.72; P = .43) from the preintervention period (2009-2013) to 2015, but assuming differential trends, we estimated a differential change in Maryland of −1.24 stays per 100 beneficiaries (95% CI, −2.46 to −0.02; P = .047). Assuming parallel trends, we found a significant increase in primary care visits (+10.6 annual visits/100 beneficiaries; 95% CI, 4.6 to 16.6 annual visits/100 beneficiaries; P = .001), but assuming differential trends, we found no change (−0.8 visits/100 beneficiaries; 95% CI, −10.6 to 9.0 visits/100 beneficiaries; P = .87). Comparing estimates with both trend assumptions, we found no consistent changes in emergency department visits, return hospital stays, HOPD use, or posthospitalization primary care visits associated with Maryland’s program. Conclusions and Relevance We did not find consistent evidence that Maryland’s hospital Global budget program was associated with reductions in hospital use or increases in primary care visits among fee-for-service Medicare beneficiaries after 2 years. Evaluations over longer periods should be pursued.
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oregon s medicaid reform and transition to Global Budgets were associated with reductions in expenditures
Health Affairs, 2017Co-Authors: John K Mcconnell, Stephanie Renfro, Richard C Lindrooth, Deborah J Cohen, Neal Wallace, Michael E. ChernewAbstract:In 2012 Oregon initiated an ambitious delivery system reform, moving the majority of its Medicaid enrollees into sixteen coordinated care organizations, a type of Medicaid accountable care organization. Using claims data, we assessed measures of access, appropriateness of care, utilization, and expenditures for five service areas (evaluation and management, imaging, procedures, tests, and inpatient facility care), comparing Oregon to the neighboring state of Washington. Overall, the transformation into coordinated care organizations was associated with a 7 percent relative reduction in expenditures across the sum of these services, attributable primarily to reductions in inpatient utilization. The change to coordinated care organizations also demonstrated reductions in avoidable emergency department visits and improvements in some measures of appropriateness of care, but also exhibited reductions in primary care visits, a potential area of concern. Oregon’s coordinated care organizations could provide les...
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The impact of Global Budgets on pharmaceutical spending and utilization: early experience from the alternative quality contract.
Inquiry : a journal of medical care organization provision and financing, 2014Co-Authors: Christopher C. Afendulis, A. Mark Fendrick, Zirui Song, Bruce E. Landon, Dana Gelb Safran, Robert E. Mechanic, Michael E. ChernewAbstract:In 2009, Blue Cross Blue Shield of Massachusetts implemented a Global budget-based payment system, the Alternative Quality Contract (AQC), in which provider groups assumed accountability for spending. We investigate the impact of Global Budgets on the utilization of prescription drugs and related expenditures. Our analyses indicate no statistically significant evidence that the AQC reduced the use of drugs. Although the impact may change over time, early evidence suggests that it is premature to conclude that Global budget systems may reduce access to medications.
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changes in health care spending and quality 4 years into Global payment
The New England Journal of Medicine, 2014Co-Authors: Zirui Song, Sherri Rose, Dana Gelb Safra, Uce E Lando, Matthew P Day, Michael E. ChernewAbstract:Background Spending and quality under Global Budgets remain unknown beyond 2 years. We evaluated spending and quality measures during the first 4 years of the Blue Cross Blue Shield of Massachusetts Alternative Quality Contract (AQC). Methods We compared spending and quality among enrollees whose physician organizations entered the AQC from 2009 through 2012 with those among persons in control states. We studied spending changes according to year, category of service, site of care, experience managing risk contracts, and price versus utilization. We evaluated process and outcome quality. Results In the 2009 AQC cohort, medical spending on claims grew an average of $62.21 per enrollee per quarter less than it did in the control cohort over the 4-year period (P<0.001). This amount is equivalent to a 6.8% savings when calculated as a proportion of the average post-AQC spending level in the 2009 AQC cohort. Analogously, the 2010, 2011, and 2012 cohorts had average savings of 8.8% (P<0.001), 9.1% (P<0.001), an...
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Global Budgets and technology intensive medical services
Healthcare, 2013Co-Authors: Zirui Song, Bruce E. Landon, Dana Gelb Safran, Michael E. Chernew, Mark A FendrickAbstract:Abstract Background In 2009–2010, Blue Cross Blue Shield of Massachusetts entered into Global payment contracts (the Alternative Quality Contract, AQC) with 11 provider organizations. We evaluated the impact of the AQC on spending and utilization of several categories of medical technologies, including one considered high value (colonoscopies) and three that include services that may be overused in some situations (cardiovascular, imaging, and orthopedic services). Methods Approximately 420,000 unique enrollees in 2009 and 180,000 in 2010 were linked to primary care physicians whose organizations joined the AQC. Using three years of pre-intervention data and a large control group, we analyzed changes in utilization and spending associated with the AQC with a propensity-weighted difference-in-differences approach adjusting for enrollee demographics, health status, secular trends, and cost-sharing. Results In the 2009 AQC cohort, total volume of colonoscopies increased 5.2 percent ( p =0.04) in the first two years of the contract relative to control. The contract was associated with varied changes in volume for cardiovascular and imaging services, but total spending on cardiovascular services in the first two years decreased by 7.4% ( p =0.02) while total spending on imaging services decreased by 6.1% ( p Conclusions As one example of a large-scale Global payment initiative, the AQC was associated with higher use of colonoscopies. Among several categories of services whose value may be controversial, the contract generally shifted volume to lower-priced facilities or services.
Ansgar Kahmen - One of the best experts on this subject based on the ideXlab platform.
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convergence of soil nitrogen isotopes across Global climate gradients
Scientific Reports, 2015Co-Authors: Joseph M Craine, Andrew J Elmore, Lixin Wang, Laurent Augusto, Troy W Baisden, E N J Brookshire, Michael D Cramer, Niles J Hasselquist, Erik A Hobbie, Ansgar KahmenAbstract:Quantifying Global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the Global scale, syntheses of the 15N:14N ratio of soil organic matter across climate gradients provide key insights into understanding Global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong Global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in 15N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ15N was invariant with MAT. At the Global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ15N showed no consistent trends across Global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and Global Budgets of gaseous N loss.
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Convergence of soil nitrogen isotopes across Global climate gradients
Scientific Reports, 2015Co-Authors: Joseph M Craine, Andrew J Elmore, Lixin Wang, Laurent Augusto, E N J Brookshire, Michael D Cramer, Niles J Hasselquist, Erik A Hobbie, W. Troy Baisden, Ansgar KahmenAbstract:Quantifying Global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the Global scale, syntheses of the N-15 : N-14 ratio of soil organic matter across climate gradients provide key insights into understanding Global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong Global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in N-15 than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8 degrees C, soil delta N-15 was invariant with MAT. At the Global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil delta N-15 showed no consistent trends across Global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and Global Budgets of gaseous N loss.
Joseph M Craine - One of the best experts on this subject based on the ideXlab platform.
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convergence of soil nitrogen isotopes across Global climate gradients
Scientific Reports, 2015Co-Authors: Joseph M Craine, Andrew J Elmore, Lixin Wang, Laurent Augusto, Troy W Baisden, E N J Brookshire, Michael D Cramer, Niles J Hasselquist, Erik A Hobbie, Ansgar KahmenAbstract:Quantifying Global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the Global scale, syntheses of the 15N:14N ratio of soil organic matter across climate gradients provide key insights into understanding Global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong Global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in 15N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ15N was invariant with MAT. At the Global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ15N showed no consistent trends across Global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and Global Budgets of gaseous N loss.
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Convergence of soil nitrogen isotopes across Global climate gradients
Scientific Reports, 2015Co-Authors: Joseph M Craine, Andrew J Elmore, Lixin Wang, Laurent Augusto, E N J Brookshire, Michael D Cramer, Niles J Hasselquist, Erik A Hobbie, W. Troy Baisden, Ansgar KahmenAbstract:Quantifying Global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the Global scale, syntheses of the N-15 : N-14 ratio of soil organic matter across climate gradients provide key insights into understanding Global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong Global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in N-15 than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8 degrees C, soil delta N-15 was invariant with MAT. At the Global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil delta N-15 showed no consistent trends across Global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and Global Budgets of gaseous N loss.
Alex Guenther - One of the best experts on this subject based on the ideXlab platform.
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response of isoprene emission to ambient co2 changes and implications for Global Budgets
Global Change Biology, 2009Co-Authors: Colette L Heald, M Wilkinson, Russell K Monson, Clement Alo, Guiling Wang, Alex GuentherAbstract:We explore the potential role of atmospheric carbon dioxide (CO2) on isoprene emissions using a Global coupled land–atmosphere model [Community Atmospheric Model–Community Land Model (CAM–CLM)] for recent (year 2000, 365ppm CO2) and future (year 2100, 717ppm CO2) conditions. We incorporate an empirical model of observed isoprene emissions response to both ambient CO2 concentrations in the long-term growth environment and short-term changes in intercellular CO2 concentrations into the MEGAN biogenic emission model embedded within the CLM. Accounting for CO2 inhibition has little impact on predictions of present-day Global isoprene emission (increase from 508 to 523TgCyr � 1 ). However, the large increases in future isoprene emissions typically predicted in models, which are due to a projected warmer climate, are entirely offset by including the CO2 effects. Projected Global isoprene emissions in 2100 drop from 696 to 479TgCyr � 1 when this effect is included, maintaining future isoprene sources at levels similar to present day. The isoprene emission response to CO2 is dominated by the long-term growth environment effect, with modulations of 10% or less due to the variability in intercellular CO2 concentration. As a result, perturbations to isoprene emissions associated with changes in ambient CO2 are largely aseasonal, with little diurnal variability. Future isoprene emissions increase by more than a factor of two in 2100 (to 1242TgCyr � 1 ) when projected changes in vegetation distribution and leaf area density are included. Changing land cover and the role of nutrient limitation on CO2 fertilization therefore remain the largest source of uncertainty in isoprene emission prediction. Although future projections suggest a compensatory balance between the effects of temperature and CO2 on isoprene emission, the enhancement of isoprene emission due to lower ambient CO2 concentrations did not compensate for the effect of cooler temperatures over the last 400 thousand years of the geologic record (including the Last Glacial Maximum).
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the tropical forest and fire emissions experiment laboratory fire measurements and synthesis of campaign data
Atmospheric Chemistry and Physics, 2008Co-Authors: Robert J Yokelson, Ted J Christian, T Karl, Alex GuentherAbstract:As part of the Tropical Forest and Fire Emissions Experiment (TROFFEE), tropical forest fuels were burned in a large, biomass-fire simulation facility and the smoke was characterized with open-path Fourier transform infrared spectroscopy (FTIR), proton-transfer reaction mass spec- trometry (PTR-MS), gas chromatography (GC), GC/PTR- MS, and filter sampling of the particles. In most cases, about one-third of the fuel chlorine ended up in the parti- cles and about one-half remained in the ash. About 50% of the mass of non-methane organic compounds (NMOC) emitted by these fires could be identified with the available instrumentation. The lab fire emission factors (EF, g com- pound emitted per kg dry fuel burned) were coupled with EF obtained during the TROFFEE airborne and ground-based field campaigns. This revealed several types of EF depen- dence on parameters such as the ratio of flaming to smol- dering combustion and fuel characteristics. The synthesis of data from the different TROFFEE platforms was also used to derive EF for all the measured species for both primary deforestation fires and pasture maintenance fires - the two main types of biomass burning in the Amazon. Many of the EF are larger than those in widely-used earlier work. This is mostly due to the inclusion of newly-available, large EF for the initially-unlofted smoldering emissions from resid- ual logs in pastures and the assumption that these emissions make a significant contribution ( 40%) to the total emissions from pasture fires. The TROFFEE EF for particles with aero- dynamic diameter <2.5 microns (EFPM2.5) is 14.8 g/kg for primary deforestation fires and 18.7 g/kg for pasture main- tenance fires. These EFPM 2.5 are significantly larger than a previous recommendation (9.1 g/kg) and lead to an estimated pyrogenic primary PM2.5 source for the Amazon that is 84% larger. New regional Budgets for biogenic and pyrogenic emissions were roughly estimated. Coupled with an estimate of secondary aerosol formation in the Amazon and source ap- portionment studies, the regional Budgets suggest that 5% of the total mass of the regionally generated NMOC end up as secondary organic aerosol within the Amazonian bound- ary layer within 1-3 days. New Global Budgets confirm that biogenic emissions and biomass burning are the two largest Global sources of NMOC with an estimated production of ap- proximately 1000 (770-1400) and 500 (250-630) Tg/yr, re- spectively. It follows that plants and fires may also be the two main Global sources of secondary organic aerosol. A limited set of emission ratios (ER) is given for sugar cane burning, which may help estimate the air quality impacts of burning this major crop, which is often grown in densely populated areas.
Robert C Rhew - One of the best experts on this subject based on the ideXlab platform.
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measuring terrestrial fluxes of methyl chloride and methyl bromide using a stable isotope tracer technique
Geophysical Research Letters, 2003Co-Authors: Robert C Rhew, M Aydin, E S SaltzmanAbstract:Author(s): Rhew, Robert C; Aydin, M.; Saltzman, E. S. | Abstract: Atmospheric methyl chloride (CH3Cl) and methyl bromide (CH3Br), compounds involved in the destruction of stratospheric ozone, are simultaneously produced and consumed by the terrestrial biosphere. Here we present a stable isotope incubation technique using13CH3Cl and 13CH3Br as tracers to simultaneously determine production and consumption fluxes in boreal forest soils from Alaska, USA. Measured uptake rates are consistent with previously reported boreal soil results for CH3Br and show a CH3Cl:CH3Br molar consumption ratio of 40:1. Boreal forest soils appear to produce small amounts of these methyl halides as well, but at rates that are negligible in their Global Budgets. This isotope tracer technique can be applied to laboratory studies of plants and other soils and to field measurements where disturbances to the system can be minimized.