Diagnosis isn\u27t enough: Understanding the connections between high health care utilization, chronic conditions and disabilities among U.S. working age adults

Background Under the ACA, new programs are being developed to enhance care coordination and reduce health care costs among people with chronic conditions, disabilities, and high utilization of health care. However, the relationships between these groups are not well understood. Objectives Our aims were to (1) identify high utilizers of health care in the U.S. working age (18–64) population, (2) examine the overlap between this group and people with chronic conditions and/or disabilities, (3) identify predictors of high service use or cost among these subpopulations, and (4) recommend approaches for stratification of individuals with high health care utilization. Methods Using pooled national data from the Medical Expenditure Panel Survey (2006–2008), we created indices to identify elevated or high utilization and cost groups. We performed descriptive analyses, bivariate comparisons and multivariate analyses to examine the relations between these populations and individuals with chronic conditions and/or disabilities. Results While the large majority of persons with high use/cost had chronic conditions, the minority of persons with chronic conditions had high health care utilization. However, among persons with chronic conditions, disability was a significant predictor of high utilization. Annual expenditures were significantly elevated among people with disabilities, particularly when activities of daily living were limited. Conclusions We conclude that medical diagnosis alone is insufficient for the development of eligibility criteria for, or the evaluation of, programs intended to better the delivery or coordination of services for high utilizers of health care services. New approaches are needed to assess functional limitations and identify ongoing needs for services and supports

DD-optimal saturated designs: a simulation study

In this work we focus on saturated $D$-optimal designs. Using recent results, we identify $D$-optimal designs with the solutions of an optimization problem with linear constraints. We introduce new objective functions based on the geometric structure of the design and we compare them with the classical $D$-efficiency criterion. We perform a simulation study. In all the test cases we observe that designs with high values of $D$-efficiency have also high values of the new objective functions.Comment: 8 pages. Preliminary version submitted to the 7th IWS Proceeding

Unbounded Human Learning: Optimal Scheduling for Spaced Repetition

In the study of human learning, there is broad evidence that our ability to retain information improves with repeated exposure and decays with delay since last exposure. This plays a crucial role in the design of educational software, leading to a trade-off between teaching new material and reviewing what has already been taught. A common way to balance this trade-off is spaced repetition, which uses periodic review of content to improve long-term retention. Though spaced repetition is widely used in practice, e.g., in electronic flashcard software, there is little formal understanding of the design of these systems. Our paper addresses this gap in three ways. First, we mine log data from spaced repetition software to establish the functional dependence of retention on reinforcement and delay. Second, we use this memory model to develop a stochastic model for spaced repetition systems. We propose a queueing network model of the Leitner system for reviewing flashcards, along with a heuristic approximation that admits a tractable optimization problem for review scheduling. Finally, we empirically evaluate our queueing model through a Mechanical Turk experiment, verifying a key qualitative prediction of our model: the existence of a sharp phase transition in learning outcomes upon increasing the rate of new item introductions.Comment: Accepted to the ACM SIGKDD Conference on Knowledge Discovery and Data Mining 201

A comparison of scavenging and deposition processes in global models: results from the WCRP Cambridge Workshop of 1995

We report on results from a World Climate Research Program workshop on representations of scavenging and deposition processes in global transport models of the atmosphere. 15 models were evaluated by comparing simulations of radon, lead, sulfur dioxide, and sulfate against each other, and against observations of these constituents. This paper provides a survey on the simulation differences between models. It identifies circumstances where models are consistent with observations or with each other, and where they differ from observations or with each other. The comparison shows that most models are able to simulate seasonal species concentrations near the surface over continental sites to within a factor of 2 over many regions of the globe. Models tend to agree more closely over source (continental) regions than for remote (polar and oceanic) regions. Model simulations differ most strongly in the upper troposphere for species undergoing wet scavenging processes. There are not a sufficient number of observations to characterize the climatology (long-term average) of species undergoing wet scavenging in the upper troposphere. This highlights the need for either a different strategy for model evaluation (e.g., comparisons on an event by event basis) or many more observations of a few carefully chosen constituents

Large thermomagnetic effects in weakly disordered Heisenberg chains

The interplay of different scattering mechanisms can lead to novel effects in transport. We show theoretically that the interplay of weak impurity and Umklapp scattering in spin-1/2 chains leads to a pronounced dip in the magnetic field dependence of the thermal conductivity $\kappa$ at a magnetic field $B \sim T$. In sufficiently clean samples, the reduction of the magnetic contribution to heat transport can easily become larger than 50% and the effect is predicted to exist even in samples with a large exchange coupling, J >> B, where the field-induced magnetization is small. Qualitatively, our theory might explain dips at $B \sim T$ observed in recent heat transport measurements on copper pyrazine dinitrate, but a fully quantitative description is not possible within our model.Comment: 5 pages, 2 figure

User and provider perspectives on emergency obstetric care in a Tanzanian rural setting: A qualitative analysis of the three delays model in a field study

The aim of this field study was to analyze the main dynamics and conflicts in attending and providing good quality delivery care in a local Tanzanian rural setting. The women and their relatives did not see the problems of pregnancy and birth in isolation but in relation to multiple other problems they were facing in the context of poverty. Local health professionals were aware of the poor quality of care at health facilities but were still blaming the community. The study describes the difficulties within the conceptual framework of thewidely used “three delays model”to disentangle different perspectives and to identify a feasible strategy of action to improve access to timely and effective emergency obstetric care. There seems to be a need for a supplementary analytic model that more clearly has the health system as the central agent responsible for improving maternal health. A modified “actantial model is suggested for that purpose

Medium and long-term adherence to postabortion contraception among women having experienced unsafe abortion in Dar es Salaam, Tanzania

<p>Abstract</p> <p>Background</p> <p>Postabortion contraceptive service is considered an effective means in addressing the problem of unsafe abortion; in spite this fact this component remains one of the weakest parts of postabortion care. In this context, the paper aims to describe the impact of a postabortion contraceptive service intervention among women admitted with complications from unsafe abortions and to explore the women's long-term contraceptive adherence.</p> <p>Methods</p> <p>392 women having experienced unsafe abortion were identified by an empathetic approach and offered postabortion contraceptive service, which included counselling on HIV and condom use. Questionnaire interviews about contraceptive use were conducted at the time of inclusion and 12 months after the abortion. Additionally, in-depth interviews were performed 6–12 months after the abortion.</p> <p>Results</p> <p>Eighty-nine percent of the women accepted postabortion contraception. Follow-up information was obtained 12 months after the abortion among 59 percent of the women. Among these, 79 percent of the married women and 84 percent of the single women stated they were using contraception at 12 months. Condom use among the single women increased significantly during the 12 months follow up.</p> <p>Conclusion</p> <p>Postabortion contraceptive services appear to be well accepted by women who are admitted with complications after an unsafe abortion and should thus be recognized as an important means in addressing the problem of unsafe abortion. In addition, counselling about HIV and condom use should be considered an essential aspect of postabortion care.</p