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排序方式: 共有9411条查询结果,搜索用时 15 毫秒
41.
Robert J. Town Douglas Wholey Roger Feldman Lawton R. Burns 《Health services research》2007,42(1P1):219-238
Objective. This paper analyzes whether the rise in managed care during the 1990s caused the increase in hospital concentration.
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
Data Sources. We assemble data from the American Hospital Association, InterStudy and government censuses from 1990 to 2000.
Study Design. We employ linear regression analyses on long differenced data to estimate the impact of managed care penetration on hospital consolidation. Instrumental variable analogs of these regressions are also analyzed to control for potential endogeneity.
Data Collection. All data are from secondary sources merged at the level of the Health Care Services Area.
Principle Findings. In 1990, the mean population-weighted hospital Herfindahl–Hirschman index (HHI) in a Health Services Area was .19. By 2000, the HHI had risen to .26. Most of this increase in hospital concentration is due to hospital consolidation. Over the same time frame HMO penetration increased three fold. However, our regression analysis strongly implies that the rise of managed care did not cause the hospital consolidation wave. This finding is robust to a number of different specifications. 相似文献
42.
The effects of patient, hospital, and physician characteristics on length of stay and mortality 总被引:14,自引:0,他引:14
This article compares the ability of hospital and physician characteristics to explain variations in length of stay and mortality, controlling for factors associated with severity of illness. The analysis is based on 54,571 discharges, covering 11 medical and five surgical conditions, from nonfederal general hospitals in one state during 1988. Results suggest that both hospital and physician characteristics are important predictors of both outcome measures. Contrary to previous research, the volume of patients with the same condition treated by the hospital increases both length of stay and mortality. The volume of patients with the same condition treated by the physician increases length of stay among patients with medical conditions, decreases length of stay among those with surgical conditions, and decreases mortality. One interesting finding is that the medical school attended by the physician influences the patient's length of stay. Findings are interpreted in light of research evidence on factors affecting medical outcomes and recent federal efforts to improve quality of care. 相似文献
43.
R Snyder J Bishop G Brodie W Burns A Coates J Levi D Raghavan M Schwarz M Tattersall D Thomson 《Cancer treatment reports》1987,71(3):273-276
Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin. 相似文献
44.
45.
A portable system for measuring cutaneous thresholds for warming and cooling. 总被引:5,自引:3,他引:2
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C J Fowler M B Carroll D Burns N Howe K Robinson 《Journal of neurology, neurosurgery, and psychiatry》1987,50(9):1211-1215
Measurement of cutaneous thermal thresholds is a valuable technique for detecting small fibre neuropathy. A robust and portable microcomputer controlled system, which separately measures thresholds for warming and cooling, is described. Thresholds at three sites have been measured; the cheek, the dorsum of the hand and the sole of the foot. Regional variability and a correlation with age have been found, indicating the sensitivity of this system. 相似文献
46.
John Polich Tim Burns Floyd E. Bloom 《Alcoholism, clinical and experimental research》1988,12(2):248-254
P300 event-related brain potentials (ERPs) were obtained from 20 pairs of male and 20 pairs of female undergraduate subjects. One member of each pair reported having a father who was alcoholic (FHP), the other reported no known alcoholic biological relative (FHN). Pair members were matched on age, height, weight, grade point average, and personal drinking history. Three auditory tasks which differed in stimulus discrimination difficulty were presented to each subject. All tasks employed 20% target and 80% standard tones with the subject required to move their index finger whenever a target stimulus was detected. No significant differences in P300 amplitude or latency were obtained between the family history subject groups, although female FHP subjects tended to have smaller P300 amplitudes than their FHN counterparts. P300 amplitude decreased with increases in the amount of self-reported alcohol consumed for FHP subjects but significantly so only for the most difficult task situation. The results suggest that the relationship between the P300 ERP and the inheritability of alcoholism is not yet clear and may be subject to modulation by task requirements, population differences, and subject sex. 相似文献
47.
The patient''s appraisal of the cosmetic result of segmental mastectomy in benign and malignant breast disease. 总被引:1,自引:0,他引:1
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Women's appraisal of the cosmetic result and their psychosocial adjustment after a standardized segmental mastectomy for benign or malignant breast disease was analyzed on the basis of a mailed questionnaire, which was satisfactorily answered by 263 (92%) of 285 women operated on consecutively. The overall result was favorable: 96.5% of the patients found the new appearance of their breast very good (30.7%), good (44.0%), or acceptable (21.8%). Women with a benign diagnosis ran a two-fold higher risk of being discontented with the new appearance of the breast than those with breast cancer. Complications of radiation therapy, preoperative concern that the breasts are important for the appearance, and anxiousness about the cosmetic result were associated with a significantly elevated risk of being less satisfied with the outcome. The main finding that it is possible to perform a locally radical operation that is highly acceptable to the woman is relevant to the surgical management of potentially malignant mammographic lesions and also to the scientific strategies for future evaluation of breast-conserving treatment modes in malignant disease. 相似文献
48.
Past studies have found that medical patients with the diagnosis of depression (comorbidity) have longer hospital lengths of stay (LOS) than those without the diagnosis of depression. This suggested that scores on a depression scale would be positively correlated with LOS. On a rehabilitation ward, 14 stroke and 17 amputee patients were given the Geriatric Depression Scale (GDS) and lengths of stay were recorded. Correlations between GDS scores and LOS were +0.575 for stroke and +0.266 for amputee patients, both in the hypothesized direction. Explanations considered included: (1) depression and medical illness each produce morbidity which summate to require increased LOS; (2) depression delays medical recovery as well as the appearance of medical recovery, and (3) discharge planning is complicated by depression. When depression is associated with inpatient medical illness, DRGs may need to be reevaluated. 相似文献
49.
D R Turner E A Haan E Jacka R S Kalucy R J Burns J O Willoughby R Crabb 《The Medical journal of Australia》1988,148(11):567, 570-567, 573
The discovery of a fragment of DNA that is linked closely to the Huntington's-disease autosomal locus offers the opportunity for the presymptomatic diagnosis of this dominantly-inherited neurodegenerative disorder. Presymptomatic testing will present individuals and society with difficult choices and responsibilities. A pilot adult presymptomatic test programme is under way for SA families. Presymptomatic testing requires intensive counselling both before and after the test. A form of prenatal test, which is applicable to a significant proportion of couples with one partner at risk of Huntington's disease, is available also. As this form of prenatal test does not change the risk status of the parent, less extensive counselling is required and testing is available nationally through the SA programme. It is anticipated that other states will develop their own diagnostic programmes in the near future. This article explains the basis for the test, its accuracy and the importance of obtaining DNA from key individuals in pedigrees of Huntington's disease. 相似文献
50.