Influencing Physician Drug Prescription Habits Towards Cost Containment

In Israel, diffusion of clinical information systems is almost universal in ambulatory medical services. The drug prescription module embedded in a widely-used electronic patient record system has the capacity to intervene and notify physicians about available generic or therapeutic substitute drugs, when their first choice is outside the insurer\u27s preferred drug list. The objective of this paper is to study how such intervention influences drug prescription habits of physicians and helps contain costs. To this end we monitored system use for 40 weeks, recording physicians’ willingness to change their choice to a substitute following system notification. Findings show higher physician compliance with generic substitutes than with therapeutic substitutes, based on a cognitive decision process upon notification, and increase in compliance over time, until stabilization. The resulting direct financial savings on expenditure for drugs, estimated to be 4.7% for chronic drugs, entail long-term savings

Extremal Optimization at the Phase Transition of the 3-Coloring Problem

We investigate the phase transition of the 3-coloring problem on random graphs, using the extremal optimization heuristic. 3-coloring is among the hardest combinatorial optimization problems and is closely related to a 3-state anti-ferromagnetic Potts model. Like many other such optimization problems, it has been shown to exhibit a phase transition in its ground state behavior under variation of a system parameter: the graph's mean vertex degree. This phase transition is often associated with the instances of highest complexity. We use extremal optimization to measure the ground state cost and the ``backbone'', an order parameter related to ground state overlap, averaged over a large number of instances near the transition for random graphs of size $n$ up to 512. For graphs up to this size, benchmarks show that extremal optimization reaches ground states and explores a sufficient number of them to give the correct backbone value after about $O(n^{3.5})$ update steps. Finite size scaling gives a critical mean degree value $\alpha_{\rm c}=4.703(28)$. Furthermore, the exploration of the degenerate ground states indicates that the backbone order parameter, measuring the constrainedness of the problem, exhibits a first-order phase transition.Comment: RevTex4, 8 pages, 4 postscript figures, related information available at http://www.physics.emory.edu/faculty/boettcher

Investigating Physicians\u27 Compliance with Drug Prescription Notifications

The objective of this study was to investigate physicians\u27 compliance with recommendations for drug substitutes embedded within an electronic medical record, to assess factors affecting compliance, and to evaluate associated cost savings. An exploratory study of all physicians in all clinics operated by a large health maintenance organization (HMO) was conducted using a transparent computerized agent that collected 1.21 million prescriptions prescribed by 647 physicians. Compliance with HMO recommendations for substitute drugs reached a 70 percent rate. Substitute type, whether generic or therapeutic, was found to be the most significant factor affecting compliance, with physician workload and age second and third in effect magnitude, respectively. Compliance was found to be non-automatic and selective, following a thoughtful cognitive process. The HMO realized at least a 4 percent reduction in costs for prescribed drugs as a result of compliance with substitute recommendations. The results can be interpreted via the lens of Organizational Justice Theory, assuming that the broad compliance with generic substitutes was driven by perception of just procedures, whereas there was no such perception in the case of therapeutic substitutes. While more research is warranted for investigating the motivations driving physicians\u27 compliance, we strongly feel that the results can be generalized to other HMOs and healthcare settings

Price and service competition with maintenance service bundling

In many equipment manufacturing industries, firms compete with each other not only on products price, but also on maintenance service. More and more traditional products oriented firms are offering their customers products bundled with maintenance service (P&S bundles). In this study, we examine firms’ incentive to offer customers products bundling with long-term maintenance or repair support service in a duopoly competitive environment. When providing P&S bundles, a firm need to determine the service level (in terms of average response time guarantee for the service in this paper) to offer and needs to build a service facility to handle the maintenance service requirements. Based on the analysis of three sub-game models, we characterize the market conditions in which only one firm, both firms or neither firm will offer P&S bundles. Finally, we analyze the affects of several market factors on firms’ strategy choices

Extremal Optimization for Graph Partitioning

Extremal optimization is a new general-purpose method for approximating solutions to hard optimization problems. We study the method in detail by way of the NP-hard graph partitioning problem. We discuss the scaling behavior of extremal optimization, focusing on the convergence of the average run as a function of runtime and system size. The method has a single free parameter, which we determine numerically and justify using a simple argument. Our numerical results demonstrate that on random graphs, extremal optimization maintains consistent accuracy for increasing system sizes, with an approximation error decreasing over runtime roughly as a power law t^(-0.4). On geometrically structured graphs, the scaling of results from the average run suggests that these are far from optimal, with large fluctuations between individual trials. But when only the best runs are considered, results consistent with theoretical arguments are recovered.Comment: 34 pages, RevTex4, 1 table and 20 ps-figures included, related papers available at http://www.physics.emory.edu/faculty/boettcher

Desenvolvimento de uma Ferramenta Web para o Cálculo do Preço de Indiferença (PI) entre os Ambientes de Contratação de Energia Elétrica

Observa-se dois ambientes no mercado brasileiro de energia, o Ambiente de Contratação Regulado (ACR) e o Ambiente de Contratação Livre (ACL). No ambiente regulado, os consumidores compram energia de uma concessionária, enquanto que no ambiente livre, contratos de energia são livremente negociados com geradores e comercializadores. Visto que existem consumidores potencialmente livres (no ACR) que desejam migrar para o ACL, é interessante o desenvolvimento de uma ferramenta pública que auxilie essa tomada de decisão