27,827 research outputs found
Automated Identification of Unhealthy Drinking Using Routinely Collected Data: A Machine Learning Approach
Background: Unhealthy drinking is prevalent in the United States and can lead to serious health and social consequences, yet it is under-diagnosed and under-treated. Identifying unhealthy drinkers can be time-consuming for primary care providers. An automated tool for identification would allow attention to be focused on patients most likely to need care and therefore increase efficiency and effectiveness.
Objectives: To build a clinical prediction tool for unhealthy drinking based solely on routinely collected demographic and laboratory data.
Methods: We obtained demographic and laboratory data on 89,325 adults seen at the University of Vermont Medical Center from 2011-2017. Logistic regression, support vector machines (SVM), k-nearest neighbor, and random forests were each used to build clinical prediction models. The model with the largest area under the receiver operator curve (AUC) was selected.
Results: SVM with polynomials of degree 3 produced the largest AUC. The most influential predictors were alkaline phosphatase, gender, glucose, and serum bicarbonate. The optimum operating point had sensitivity 31.1%, specificity 91.2%, positive predictive value 50.4%, and negative predictive value 82.1%. Application of the tool increased the prevalence of unhealthy drinking from 18.3% to 32.4%, while reducing the target population by 22%.
Limitations: Universal screening was not used during the time data was collected. The prevalence of unhealthy drinking among those screened was 60% suggesting the AUDIT-C was administered to confirm rather than screen for unhealthy drinking.
Conclusion: An automated tool, using commonly available data, can identify a subset of patients who appear to warrant clinical attention for unhealthy drinking
Time evolution of the Partridge-Barton Model
The time evolution of the Partridge-Barton model in the presence of the
pleiotropic constraint and deleterious somatic mutations is exactly solved for
arbitrary fecundity in the context of a matricial formalism. Analytical
expressions for the time dependence of the mean survival probabilities are
derived. Using the fact that the asymptotic behavior for large time is
controlled by the largest matrix eigenvalue, we obtain the steady state values
for the mean survival probabilities and the Malthusian growth exponent. The
mean age of the population exhibits a power law decayment. Some Monte
Carlo simulations were also performed and they corroborated our theoretical
results.Comment: 10 pages, Latex, 1 postscript figure, published in Phys. Rev. E 61,
5664 (2000
Conflicting priorities: evaluation of an intervention to improve nurse-parent relationships on a Tanzanian paediatric ward.
BACKGROUND: Patient, or parent/guardian, satisfaction with health care provision is important to health outcomes. Poor relationships with health workers, particularly with nursing staff, have been reported to reduce satisfaction with care in Africa. Participatory research approaches such as the Health Workers for Change initiative have been successful in improving provider-client relationships in various developing country settings, but have not yet been reported in the complex environment of hospital wards. We evaluated the HWC approach for improving the relationship between nurses and parents on a paediatric ward in a busy regional hospital in Tanzania. METHODS: The intervention consisted of six workshops, attended by 29 of 31 trained nurses and nurse attendants working on the paediatric ward. Parental satisfaction with nursing care was measured with 288 parents before and six weeks after the workshops, by means of an adapted Picker questionnaire. Two focus-group discussions were held with the workshop participants six months after the intervention. RESULTS: During the workshops, nurses demonstrated awareness of poor relationships between themselves and mothers. To tackle this, they proposed measures including weekly meetings to solve problems, maintain respect and increase cooperation, and representation to administrative forces to request better working conditions such as equipment, salaries and staff numbers. The results of the parent satisfaction questionnaire showed some improvement in responsiveness of nurses to client needs, but overall the mean percentage of parents reporting each of 20 problems was not statistically significantly different after the intervention, compared to before it (38.9% versus 41.2%). Post-workshop focus-group discussions with nursing staff suggested that nurses felt more empathic towards mothers and perceived an improvement in the relationship, but that this was hindered by persisting problems in their working environment, including poor relationships with other staff and a lack of response from hospital administration to their needs. CONCLUSION: The intended outcome of the intervention was not met. The priorities of the intervention--to improve nurse-parent relationships--did not match the priorities of the nursing staff. Development of awareness and empathy was not enough to provide care that was satisfactory to clients in the context of working conditions that were unsatisfactory to nurses
A Solution of the Maxwell-Dirac Equations in 3+1 Dimensions
We investigate a class of localized, stationary, particular numerical
solutions to the Maxwell-Dirac system of classical nonlinear field equations.
The solutions are discrete energy eigenstates bound predominantly by the
self-produced electric field.Comment: 12 pages, revtex, 2 figure
Philosophical Agents
Abstraction is the technique we use to deal with complexity. What is the proper kind and level of abstraction for complex software agents? We think it would be reasonable to endow agents with a philosophy. Then, by understanding their philosophies, we can use them more effectively. To endow agents with ethical principles, developers need an architecture that supports explicit goals, principles and capabilities, as well as laws and ways to sanction or punish miscreants. All of the ethical approaches described in this article are single-agent in orientation and encode other agents implicitly
The limits of process: On (re)reading Henri Bergson
This article offers a reading of the work of Henri Bergson as it pertains to organizations through the lens of ideas drawn from critical realism. It suggests an alternative to interpretations based on a stark division between process and realist perspectives. Much of the existing literature presents a rather partial view of Bergson’s work. A review suggests some interesting parallels with themes in critical realism, notably the emergence of mind. Critical realism has a focus on process at its heart, but is also concerned with how the products of such processes become stabilized and form the conditions for action. This suggests that attention might usefully be paid to the relationship between organizational action and the sedimented practices grouped under the heading of ‘routines’. More attention to Bergson’s account of the relationship between instinct, intuition and intelligence provides a link to the social character of thought, something which can be mapped on to Archer’s work on reflexivity and the ‘internal conversation’. This suggests that our analyses need to pay attention to both memory and history, to building and dwelling, rather than the one-sided focus found in some process theory accounts
Recommended from our members
The Human Right to Food
The idea of universal human rights is a powerful one. Every person, wherever they are born and regardless of their social status, is entitled to the enjoyment of certain inalienable basic rights. Human rights are indivisible: the denial of one right affects the enjoyment of others; hence the intrinsic link between the basic rights to housing, food, and healt
Data clustering and noise undressing for correlation matrices
We discuss a new approach to data clustering. We find that maximum likelihood
leads naturally to an Hamiltonian of Potts variables which depends on the
correlation matrix and whose low temperature behavior describes the correlation
structure of the data. For random, uncorrelated data sets no correlation
structure emerges. On the other hand for data sets with a built-in cluster
structure, the method is able to detect and recover efficiently that structure.
Finally we apply the method to financial time series, where the low temperature
behavior reveals a non trivial clustering.Comment: 8 pages, 5 figures, completely rewritten and enlarged version of
cond-mat/0003241. Submitted to Phys. Rev.
Comments on Anomaly Cancellations by Pole Subtractions and Ghost Instabilities with Gravity
We investigate some aspects of anomaly cancellation realized by the
subtraction of an anomaly pole, stressing on some of its properties in
superspace. In a local formulation these subtractions can be described in terms
of a physical scalar, an axion and related ghosts. They appear to be necessary
for the unitarization of the theory in the ultraviolet, but they may generate
an infrared instability of the corresponding effective action, signalled by
ghost condensation. In particular the subtraction of the superanomaly multiplet
by a pole in superspace is of dubious significance, due to the different nature
of the chiral and conformal anomalies. In turn, this may set more stringent
constraints on the coupling of supersymmetric theories to gravity.Comment: 18 pages. Revised version. To appear in "Classical and Quantum
Gravity
- …