Coverage with evidence development: applications and issues

Copyright © Cambridge University Press, 2010OBJECTIVES: The aim of this study was to describe the current issues surrounding Coverage with Evidence Development (CED). CED is characterized by restricted coverage for a new technology in parallel with targeted research when the stated goal of the research or data collection is to provide definitive evidence for the clinical or cost-effectiveness impact of the new technology. METHODS: Presented here is information summarized and interpreted from presentations and discussions at the 2008 Health Technology Assessment International (HTAi) meeting and additional information from the medical literature. This study describes the differences between CED and other conditional coverage agreements, provides a brief history of CED, describes real-world examples of CED, describes the areas of consensus between the stakeholders, discusses the areas for future negotiation between stakeholders, and proposes criteria to assist stakeholders in determining when CED could be appropriate. RESULTS: Payers could interpret the evidence obtained from a CED program either positively or negatively, and a range of possible changes to the reimbursement status of the new technology may result. Striking an appropriate balance between the demands for prompt access to new technology and acknowledging that some degree of uncertainty will always exist is a critical challenge to the uptake of this innovative form of conditional coverage. CONCLUSIONS: When used selectively for innovative procedures, pharmaceuticals, or devices in the appropriate disease areas, CED may provide patients access to promising medicines or technologies while data to minimize uncertainty are collected.The development of the manuscript was funded by Medicines Australi

Virtual Inclusion

Several recent knowledge-representation schemes have used virtual copies for storage efficiency. Virtual copes are confusing. In the course of trying to understand, implement, and use Jon Doyle's SDL virtual copy mechanism, we encountered difficulties that led us to define an extension of virtual copies we call virtual inclusion. Virtual inclusion has interesting similarities to the environment structures maintained by a program in a block-structured language. It eliminates the clumsy typed part mechanism of SDL, and handles properly a proposed test of sophisticated virtual copy schemes.MIT Artificial Intelligence Laborator

Regional heat-flow variations across the sedimented Juan de Fuca Ridge eastern flank: constraints on lithospheric cooling and lateral hydrothermal heat transport

Journal ArticleSeafloor heat flow has been estimated continuously along a transect on the sedimented eastern flank of the Juan de Fuca Ridge to provide constraints on the scale and rate of lateral heat and fluid transport in the upper igneous crust, and on the total flux from the young lithosphere beneath. The profile extends from 20 km east of the ridge axis, where turbidite sediments lap onto the oceanic crust at an age of less than 1 Ma, and ends 110 km east of the axis over 3.6 Ma crust

Monitoring aquifer recharge using repeated high-precision gravity measurements: a pilot study in South Weber, Utah

Journal ArticleRepeated high-precision gravity surveys were conducted over two infiltration cycles on an alluvial-fan aquifer system at the mouth of Weber Canyon in northern Utah as part of the Weber River Basin Aquifer Storage and Recovery Pilot Project (WRBASR). Gravity measurements collected before, during, and after infiltration events indicate that a perched groundwater mound formed during infiltration events and decayed smoothly following infiltration. Data also suggest the groundwater mound migrated gradually south-southwest from the surface infiltration site

Algebraic and combinatorial aspects of sandpile monoids on directed graphs

The sandpile group of a graph is a well-studied object that combines ideas from algebraic graph theory, group theory, dynamical systems, and statistical physics. A graph's sandpile group is part of a larger algebraic structure on the graph, known as its sandpile monoid. Most of the work on sandpiles so far has focused on the sandpile group rather than the sandpile monoid of a graph, and has also assumed the underlying graph to be undirected. A notable exception is the recent work of Babai and Toumpakari, which builds up the theory of sandpile monoids on directed graphs from scratch and provides many connections between the combinatorics of a graph and the algebraic aspects of its sandpile monoid. In this paper we primarily consider sandpile monoids on directed graphs, and we extend the existing theory in four main ways. First, we give a combinatorial classification of the maximal subgroups of a sandpile monoid on a directed graph in terms of the sandpile groups of certain easily-identifiable subgraphs. Second, we point out certain sandpile results for undirected graphs that are really results for sandpile monoids on directed graphs that contain exactly two idempotents. Third, we give a new algebraic constraint that sandpile monoids must satisfy and exhibit two infinite families of monoids that cannot be realized as sandpile monoids on any graph. Finally, we give an explicit combinatorial description of the sandpile group identity for every graph in a family of directed graphs which generalizes the family of (undirected) distance-regular graphs. This family includes many other graphs of interest, including iterated wheels, regular trees, and regular tournaments.Comment: v2: Cleaner presentation, new results in final section. Accepted for publication in J. Combin. Theory Ser. A. 21 pages, 5 figure

Eyespray Vaccination: Infectivity and Development of Immunity to Eimeria acervulina and Eimeria tenella

The infectivity of a coccidiosis vaccine and its ability to immunize chickens against two species of Eimeria was examined. The vaccine was administered to newly-hatched chicks by spraying directly onto the eye. The method resulted in a high proportion of chicks infected with E. acervulina and E. tenella. Vaccinated birds reared in cages in the absence of reinfection did not develop immunity to either species by 4 wk of age, but birds reared in floor pens developed immunity to both E. acervulina and E. tenella

The Submillimeter Polarization Spectrum of M17

We present 450 {\mu}m polarimetric observations of the M17 molecular cloud obtained with the SHARP polarimeter at the Caltech Submillimeter Observatory. Across the observed region, the magnetic field orientation is consistent with previous submillimeter and far-infrared polarization measurements. Our observations are centered on a region of the molecular cloud that has been compressed by stellar winds from a cluster of OB stars. We have compared these new data with previous 350 {\mu}m polarimetry and find an anti-correlation between the 450 to 350 {\mu}m polarization magnitude ratio and the ratio of 21 cm to 450 {\mu}m intensity. The polarization ratio is lower near the east end of the studied region where the cloud is exposed to stellar winds and radiation. At the west end of the region, the polarization ratio is higher. We interpret the varying polarization spectrum as evidence supporting the radiative alignment torque (RAT) model for grain alignment, implying higher alignment efficiency in the region that is exposed to a higher anisotropic radiation field.Comment: 24 pages, 10 figure

Microwave-assisted synthesis and electrochemical evaluation of VO2 (B) nanostructures

Understanding how intercalation materials change during electrochemical operation is paramount to optimizing their behaviour and function and in situ characterization methods allow us to observe these changes without sample destruction. Here we first report the improved intercalation properties of bronze phase vanadium dioxide VO2 (B) prepared by a microwave-assisted route which exhibits a larger electrochemical capacity (232 mAh g-1) compared with VO2 (B) prepared by a solvothermal route (197 mAh g-1). These electrochemical differences have also been followed using in situ X-ray absorption spectroscopy allowing us to follow oxidation state changes as they occur during battery operation