Herd behavior and investment Ottaviani, Marco; Sørensen, Peter; Scharfstein, David S ...
The American economic review,
06/2000, Letnik:
90, Številka:
3
Journal Article
Este artigo desenvolve uma estrutura conceitual geral para a análise das políticas corporativas de gestão do risco. Começamos observando que, se as fontes internas de financiamento são mais custosas ...para as corporações do que os fundos gerados internamente, normalmente haverá um benefício ao hedging: o hedging agrega valor na medida em que ajuda a garantir que uma corporação tenha fundos internos disponíveis suficientes para aproveitar oportunidades atraentes de investimento. Em seguida, afirmamos que essa simples observação tem amplas e variadas implicações para a elaboração das estratégias de gestão do risco. Delineamos como essas estratégias deveriam depender de fatores como choques em investimento e oportunidades de financiamento. Também abordamos estratégias de hedging para taxas de câmbio no caso de multinacionais, bem como estratégias envolvendo instrumentos "não lineares", como as opções.
The impact of the Trauma Collaborative Care (TCC) program on surgeon confidence in managing the psychosocial sequelae of orthopaedic trauma was evaluated as part of a larger prospective, multisite, ...cluster clinical trial. We compared confidence and perceived resource availability among surgeons practicing in trauma centers that implemented the TCC program with orthopaedic trauma surgeons in similar trauma centers that did not implement the TCC.
Prospective cohort design.
Level-I trauma centers.
Attending surgeons and fellows (N = 95 Pre and N = 82 Post).
Self-report 10-item measure of surgeon confidence in managing psychosocial issues associated with trauma and perceived availability of support resources.
Analyses, performed on the entire sample and repeated on the subset of 52 surgeons who responded to the survey at both times points, found surgeons at intervention sites experienced a significantly greater positive improvement (P < 0.05) in their (1) belief that they have strategies to help orthopaedic trauma patients change their psychosocial situation; (2) confidence in making appropriate referrals for orthopaedic trauma patients with psychosocial problems; and (3) belief that they have access to information to guide the management of psychosocial issues related to recovery.
Initial data suggest that the establishment of the TCC program can improve surgeons' perceived availability of resources and their confidence in managing the psychosocial sequelae after injury. Further studies will be required to determine if this translates into beneficial patient effects.
Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
Severe foot and ankle injuries are complex and challenging to treat, often requiring multiple operations to salvage the limb contributing to a prolonged healing period. There is some evidence to ...suggest that early amputation for some patients may result in better long-term outcomes than limb salvage. The challenge is to identify the regional injury burden for an individual that would suggest a better outcome with an amputation. The OUTLET study is a prospective, multicenter observational study comparing 18-month outcomes after limb salvage versus early amputation among patients aged 18-60 years with severe distal tibia, ankle, and foot injuries. This study aims to build upon the previous work of the Lower Extremity Assessment Project by identifying the injury and patient characteristics that help define a subgroup of salvage patients who will have better outcomes had they undergone a transtibial amputation.
There is continuing interest in the longer term effects of highly active antiretroviral therapy (HAART) on the risk of cardiopulmonary events. We assessed this using updated administrative data from ...an open retrospective cohort of HIV-infected persons receiving care from the US Veterans Affairs (VA). Information on 41,213 HIV-infected patients receiving VA care between January 1993 and December 2003 was included. Patients were followed for an average of 4 years or 168,213 person-years of follow-up. The death rate fell from 20.9 deaths per 100 patient-years of observation in 1995 to 5.2 deaths per 100 patient-years in 2003. In patient-level analysis, adjusted hazard ratios for death dropped precipitously for all races to a low of 0.18 (95% confidence interval0.15 to 0.23) at 72 months of exposure to HAART. Hazards for serious cardiovascular events remained near 1.0 for exposure to HAART, and hazards for serious cardiovascular events, stroke, or death were only slightly higher than for death alone. No selection effects or secular trends were found. The benefits of HAART continued to increase in the 8 years after introduction and with 6 years of individual use. The risk of serious cardiovascular events should be factored into individual patient management but does not pose an important public health risk.
This paper analyzes the ways in which financially distressed firms try to avoid bankruptcy through public and private debt restructurings, asset sales, mergers, and capital expenditure reductions. ...Our main finding is that a firm's debt structure affects the way financially distressed firms restructure. The combination of secured private debt and numerous public debt issues seems to impede out-of-court restructurings and increases the probability of a Chapter 11 filing. In addition, we find that, while asset sales are a way of avoiding Chapter 11, they are limited by industry factors: firms in distressed and highly leveraged industries are less prone to sell assets.
Multiple options are now available for prophylaxis of opportunistic infections related to the acquired immunodeficiency syndrome (AIDS). However, because of differences in incidence rates as well as ...drug efficacy, toxicity, and costs, the role of different types of prophylaxis remains uncertain.
To determine the clinical impact, cost, and cost-effectiveness of strategies for preventing opportunistic infections in patients with advanced human immunodeficiency virus (HIV) disease.
We developed a Markov simulation model to compare different strategies for prophylaxis of Pneumocystis carinii pneumonia (PCP), toxoplasmosis, Mycobacterium avium complex (MAC) infection, fungal infections, and cytomegalovirus (CMV) disease in HIV-infected patients. Data for the model were derived from the Multicenter AIDS Cohort Study, randomized controlled trials, and the national AIDS Cost and Services Utilization Survey.
Projected life expectancy, quality-adjusted life expectancy, total lifetime direct medical costs, and cost-effectiveness in dollars per quality-adjusted life-year (QALY) saved.
For patients with CD4 cell counts of 0.200 to 0.300 x 10(9)/L (200-300/microL) who receive no prophylaxis, we projected a quality-adjusted life expectancy of 39.08 months and average total lifetime costs of $40288. Prophylaxis for PCP and toxoplasmosis with trimethoprim-sulfamethoxazole for patients with CD4 cell counts of 0.200 x 10(9)/L (200/microL) or less increased quality-adjusted life expectancy to 42.56 months, implying an incremental cost of $16000 per QALY saved. Prophylaxis for MAC for patients with CD4 cell counts of 0.050 x 10(9)/L (50/microL) or less produced smaller gains in quality-adjusted life expectancy; incremental cost-effectiveness ratios were $35000 per QALY saved for azithromycin and $74000 per QALY saved for rifabutin. Oral ganciclovir for the prevention of CMV infection was the least cost-effective prophylaxis ($314000 per QALY saved). Results were most sensitive to the risk of developing an opportunistic infection, the impact of opportunistic infection history on long-term survival, and the cost of prophylaxis.
The cost-effectiveness of prophylaxis against HIV-related opportunistic infections varies widely, but prophylaxis against PCP or toxoplasmosis and against MAC delivers the greatest comparative value. In an era of limited resources, these results can be used to set priorities and explore new alternatives for improving HIV patient care.
Studies have suggested that patient-centered collaborative care in the early phases of recovery may assist providers and patients in managing the multifactorial consequences of injury and may lead to ...better outcomes. This cluster-controlled trial, conducted at 12 U.S. Level-I trauma centers, was designed to evaluate the impact of the Trauma Collaborative Care (TCC) program on 1-year outcomes following severe musculoskeletal injury.
Patients with high-energy orthopaedic trauma requiring surgical fixation were prospectively enrolled. Six sites implemented the TCC intervention as well as the Trauma Survivors Network (TSN), and the other 6 sites provided the standard of care. Participants were followed for 1 year, and a composite primary outcome measure composed of the Short Musculoskeletal Function Assessment (SMFA) Dysfunction Index, Patient Health Questionnaire-9 (PHQ-9), and Posttraumatic Stress Disorder Checklist (PCL) was assessed. A 2-stage, Bayesian hierarchical statistical procedure was used to characterize treatment effects. Sensitivity analyses were conducted to account for an error in the delivery of the intervention.
There were 378 patients enrolled at 6 trauma centers implementing the TCC program, and 344 patients enrolled at 6 trauma centers providing usual care. Patient utilization of treatment components varied across the intervention sites: 29% of patients in the intervention group received all 5 key components (TSN handbook education, peer visits, recovery assessment, and calls before and after recovery assessment). Posterior estimates of the intention-to-treat effect suggested that the intervention did not have an appreciable effect: the odds of the composite outcome for the TCC group increased by 5% (95% credible interval, -40% to 63%). The estimates of the effect of receiving all 5 key intervention components were similar.
Despite prior work showing early positive effects, this analysis suggests that the TCC program as delivered did not have positive effects on patient outcomes at 1 year. It is not known whether programs that improve compliance or target specific subgroups would better meet the psychosocial needs of trauma survivors.
Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.
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