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Registry-based trials have emerged as a potentially cost-saving study methodology. Early estimates of cost savings, however, conflated the benefits associated with registry utilisation and those associated with other aspects of pragmatic trial designs, which might not all be as broadly applicable. In this study, we sought to build a practical tool that investigators could use across disciplines to estimate the ranges of potential cost differences associated with implementing registry-based trials versus standard clinical trials.
Methods:
We built simulation Markov models to compare unique costs associated with data acquisition, cleaning, and linkage under a registry-based trial design versus a standard clinical trial. We conducted one-way, two-way, and probabilistic sensitivity analyses, varying study characteristics over broad ranges, to determine thresholds at which investigators might optimally select each trial design.
Results:
Registry-based trials were more cost effective than standard clinical trials 98.6% of the time. Data-related cost savings ranged from $4300 to $600,000 with variation in study characteristics. Cost differences were most reactive to the number of patients in a study, the number of data elements per patient available in a registry, and the speed with which research coordinators could manually abstract data. Registry incorporation resulted in cost savings when as few as 3768 independent data elements were available and when manual data abstraction took as little as 3.4 seconds per data field.
Conclusions:
Registries offer important resources for investigators. When available, their broad incorporation may help the scientific community reduce the costs of clinical investigation. We offer here a practical tool for investigators to assess potential costs savings.
Prevention of Clostridioides difficile infection (CDI) is a national priority and may be facilitated by deployment of the Targeted Assessment for Prevention (TAP) Strategy, a quality improvement framework providing a focused approach to infection prevention. This article describes the process and outcomes of TAP Strategy implementation for CDI prevention in a healthcare system.
Methods:
Hospital A was identified based on CDI surveillance data indicating an excess burden of infections above the national goal; hospitals B and C participated as part of systemwide deployment. TAP facility assessments were administered to staff to identify infection control gaps and inform CDI prevention interventions. Retrospective analysis was performed using negative-binomial, interrupted time series (ITS) regression to assess overall effect of targeted CDI prevention efforts. Analysis included hospital-onset, laboratory-identified C. difficile event data for 18 months before and after implementation of the TAP facility assessments.
Results:
The systemwide monthly CDI rate significantly decreased at the intervention (β2, −44%; P = .017), and the postintervention CDI rate trend showed a sustained decrease (β1 + β3; −12% per month; P = .008). At an individual hospital level, the CDI rate trend significantly decreased in the postintervention period at hospital A only (β1 + β3, −26% per month; P = .003).
Conclusions:
This project demonstrates TAP Strategy implementation in a healthcare system, yielding significant decrease in the laboratory-identified C. difficile rate trend in the postintervention period at the system level and in hospital A. This project highlights the potential benefit of directing prevention efforts to facilities with the highest burden of excess infections to more efficiently reduce CDI rates.
On his way to his inauguration in Washington, DC, in February 1861, Abraham Lincoln stopped at Independence Hall in Philadelphia to raise a flag. “I have never had a feeling politically that did not spring from the sentiments embodied in the Declaration of Independence,” he told the assembled crowd. The president-elect went on to say that the Declaration was not written merely to justify the separation of the colonies from Great Britain, but to give “liberty, not alone to the people of this country, but hope to the world, for all future time. It was that which gave promise that in due time the weights should be lifted from the shoulders of all men, and that all should have an equal chance. This is a sentiment embodied in that Declaration of Independence.” Lincoln continued that if the nation could not be saved on the basis of the Declaration, it would be “truly awful.” And, as he was speaking off the cuff, he said, “I was about to say I would rather be assassinated on this spot than surrender it.”
Icequakes at or near the bed of a glacier have the potential to allow us to investigate the interaction of ice with the underlying till or bedrock. Understanding this interaction is important for studying basal sliding of glaciers and ice streams, a critical process in ice dynamics models used to constrain future sea-level rise projections. However, seismic observations on glaciers can be dominated by seismic energy from surface crevassing. We present a method of automatically detecting basal icequakes and discriminating them from surface crevassing, comparing this method to a commonly used spectrum-based method of detecting icequakes. We use data from Skeidararjökull, an outlet glacier of the Vatnajökull Ice Cap, South-East Iceland, to demonstrate that our method outperforms the commonly used spectrum-based method. Our method detects a higher number of basal icequakes, has a lower rate of incorrectly identifying crevassing as basal icequakes and detects an additional, spatially independent basal icequake cluster. We also show independently that the icequakes do not originate from near the glacier surface. We conclude that the method described here is more effective than currently implemented methods for detecting and discriminating basal icequakes from surface crevassing.
The use of grammars in design and analysis has been set back by the lack of automated ways to induce them from arbitrarily structured datasets. Machine translation methods provide a construct for inducing grammars from coded data which have been extended to be used for design through pre-coded design data. This work introduces a four-step process for inducing grammars from un-coded structured datasets which can constitute a wide variety of data types, including many used in the design. The method includes: (1) extracting objects from the data, (2) forming structures from objects, (3) expanding structures into rules based on frequency, and (4) finding rule similarities that lead to consolidation or abstraction. To evaluate this method, grammars are induced from generated data, architectural layouts and three-dimensional design models to demonstrate that this method offers usable grammars automatically which are functionally similar to grammars produced by hand.
Usually pictured in relations of opposition, political parties are sometimes inclined to make alliances. This article examines the ethical questions such arrangements give rise to. It considers first the formal characteristics of an alliance as a distinctive form of association, moving on to examine what reasons for alliance are good reasons. Intrinsic arguments that invoke epistemic or democratic criteria, and instrumental arguments that cite areas of shared programme or imperfect institutions, are weighed in turn, with the latter judged to be more consistent with the partisan ethos. The final section examines the normative standards to which alliances should be held once formed.
Objectives: Good glycemic control is an important goal of diabetes management. Late adolescents with type 1 diabetes (T1D) are at risk for poor glycemic control as they move into young adulthood. For a subset of these patients, this dysregulation is extreme, placing them at risk for life-threatening health complications and permanent cognitive declines. The present study examined whether deficiency in emotional decision making (as measured by the Iowa Gambling Task; IGT) among teens with T1D may represent a neurocognitive risk factor for subsequent glycemic dysregulation. Methods: As part of a larger longitudinal study, a total of 241 high-school seniors (147 females, 94 males) diagnosed with T1D underwent baseline assessment that included the IGT. Glycated hemoglobin (HbA1c), which reflects glycemic control over the course of the past 2 to 3 months, was also assessed at baseline. Of the 241,189 (127 females, 62 males, mean age=17.76, mean HbA1c=8.11) completed HbA1c measurement 1 year later. Results: Baseline IGT performance in the impaired range (per norms) was associated with greater dysregulation in glycemic control 1 year later, as evidenced by an average increase in HbA1c of 2%. Those with normal IGT scores (per norms) exhibited a more moderate increase in glycemic control, with an HbA1c increase of 0.7%. Several IGT scoring approaches were compared, showing that the total scores collapsed across all trials was most sensitive to change in glycemic control. Conclusions: IGT assessment offers promise as a tool for identifying late adolescents at increased risk for glycemic dysregulation. (JINS, 2017, 23, 204–213)
This study examines maritime routes between ports along the Atlantic coast of the US, utilising Automated Identification System (AIS) data for the years 2010 through 2012. The delineation of vessel routes conducted in this study was motivated by development planned for offshore Wind Energy Areas (WEAs) along the Atlantic coast of the US and the need to evaluate the effect of these development areas on commercial shipping. To this end, available AIS data were processed to generate commercial vessel tracks for individual vessels, though cargo vessels are the focus in this study. The individual vessel tracks were sampled at transects placed along the Atlantic coast. The transect samples were analysed and partitioned by voyages between Atlantic ports to facilitate computation of vessel routes between ports. The route boundary analysis utilised a definition from UK guidance in which routes' boundaries encompassed 95% of the vessel traffic between ports. In addition to delineating route boundaries, we found multi-modal transverse distributions of vessels for well-travelled routes, which indicated preference for lanes of travel within the delineated routes.
We present the results of two 2.3 μm near-infrared (NIR) radial velocity (RV) surveys to detect exoplanets around 36 nearby and young M dwarfs. We use the CSHELL spectrograph (R ~ 46,000) at the NASA InfraRed Telescope Facility (IRTF), combined with an isotopic methane absorption gas cell for common optical path relative wavelength calibration. We have developed a sophisticated RV forward modeling code that accounts for fringing and other instrumental artifacts present in the spectra. With a spectral grasp of only 5 nm, we are able to reach long-term radial velocity dispersions of ~20–30 m s−1 on our survey targets.
Vegetation affects feedbacks in Earth's hydrologic system, but is constrained by physiological adaptations. In extant ecosystems, the mechanisms controlling plant water used can be measured experimentally; for extinct plants in the recent geological past, water use can be inferred from nearest living relatives, assuming minimal evolutionary change. In deep time, where no close living relatives exist, fossil material provides the only information for inferring plant water use. However, mechanistic models for extinct plant water use must be built on first principles and tested on extant plants. Plants serve as a conduit for water movement from the soil to the atmosphere, constrained by tissue-level construction and gross architecture. No single feature, such as stomata or veins, encompasses enough of the complexity underpinning water-use physiology to serve as the basis of a model of functional water use in all (or perhaps any) extinct plants. Rather, a “functional whole plant” model must be used. To understand the interplay between plant and atmosphere, water use in relation to environmental conditions is investigated in an extinct plant, the seed fern Medullosa ((Division Pteridospermatophyta), by reviewing methods for reconstructing physiological variables such as leaf and stem hydraulic capacity, photosynthetic rate, transpiration rate, stomatal conductance, and albedo. Medullosans had the potential for extremely high photosynthetic and assimilation rates, water transport, stomatal conductance, and transpiration—rates comparable to later angiosperms. When these high growth and gas exchange rates of medullosans are combined with the unique atmospheric gas composition of the late Paleozoic atmosphere, complex vegetation-environmental feedbacks are expected despite their basal phylogenetic position relative to post-Paleozoic seed plants.
Trends of falling membership and support spell a time of crisis for political parties, possibly of transformation. Dilemmas of principle arise: should partisans revise their normative commitments in whatever way garners new supporters, or would that be to sell their party’s soul? This article investigates this as a problem of intergenerational obligation, examining what consideration (if any) partisans owe their party’s past and future. It seeks to show the limits of conceiving partisanship as a ‘presentist’ activity that is legitimately governed exclusively by the concerns of the present generation, and argues that it must include some notion of showing loyalty to the actions of predecessors and advancing the prospects of those to come. Two corresponding norms of ethical partisanship – fidelity and sustainability – are outlined and discussed. The article’s goal is to refine our concept of what a party is, and in so doing contribute to a broader ethics of activism.