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Measuring hospital efficiency with frontier cost functions 总被引:1,自引:0,他引:1
This paper uses a stochastic frontier multiproduct cost function to derive hospital-specific measures of inefficiency. The cost function includes direct measures of illness severity, output quality, and patient outcomes to reduce the likelihood that the inefficiency estimates are capturing unmeasured differences in hospital outputs. Models are estimated using data from the AHA Annual Survey, Medicare Hospital Cost Reports, and MEDPAR. We explicitly test the assumption of output endogeneity and reject it in this application. We conclude that inefficiency accounts for 13.6 percent of total hospital costs. This estimate is robust with respect to model specification and approaches to pooling data across distinct groups of hospitals. 相似文献
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Humeral head replacement for glenohumeral arthritis 总被引:1,自引:0,他引:1
From July 1977 through March of 1983, humeral head replacement was performed on 35 shoulders with osteoarthritis and 32 shoulders with rheumatoid arthritis and followed-up for an average of 9.3 years. Satisfactory pain relief was achieved in 44 (66%) and 52 of the shoulders (78%) were described by patients as being much better or better. Active elevation was improved from an average of 84 degrees to an average of 110 degrees with external rotation improving from 20 degrees to 44 degrees. Strength improvement also occurred. Only three complications developed, and these did not affect the final outcome. Because of moderate or severe pain, 12 shoulders (18%) required revision to total shoulder arthroplasty, and all patients were relieved of their pain. The result ratings were excellent in 10 shoulders, satisfactory in 23, and unsatisfactory in 34 (51%). With longer follow-up, a satisfactory level of pain relief may not continue for those patients with osteoarthritis and rheumatoid arthritis who have had humeral head replacement alone. Whereas this form of treatment should certainly be considered in those patients who have inadequate glenoid bone to support a glenoid implant and probably be considered in younger patients or patients who wish to remain more active, these latter patients must be fully appraised that the probability of continuing pain relief is less than has often been appreciated. 相似文献
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BACKGROUND: Few studies have examined intrafamilial patterns of cardiovascular disease (CVD) risk factors in African-American families or identified potential influences on these patterns. This study examines the effects of age and sex of child on correlations between siblings during childhood as well as between mothers and their offspring in African-American families at two points in time. METHODS: CVD risk factors were assessed in a sample of 267 pairs of African-American siblings and their mothers. One hundred nine of these families were selected for a second assessment of CVD risk factors approximately 28 months later. RESULTS: Older siblings had significantly greater correlations than younger siblings with mothers' low-density lipoproteins (r = 0.61 versus r = 0.43 for older and younger siblings, respectively), apolipoprotein A-I (r = 0. 46 versus r = 0.16), and lipoprotein (a) (r = 0.71 versus r = 0.34). Correlations between female siblings were significantly higher than between male siblings for total cholesterol (r = 0.74 versus r = 0. 18 for female versus male siblings), triglycerides (r = 0.56 versus r = 0.05), and apolipoprotein B (r = 0.72 versus r = 0.31); they were also higher between female siblings than between mixed-sex siblings for measures of adiposity (r = 0.46 versus r = 0.19) and total cholesterol (r = 0.74 versus r = 0.27). CONCLUSIONS: Significant intrafamilial correlations for African-American children were influenced by both age and sex of siblings, reflecting potential genetic and environmental influences. Assessing family patterns of CVD risk factors in high-risk populations may assist in the early identification of children who can benefit most from intervention. 相似文献
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In binding assays, both dynorphin B and alpha-neoendorphin are relatively selective for the kappa1b site, unlike U50,488H which has high affinity for both kappa1a and kappa1b sites. In vivo, U50,488H, dynorphin B and alpha-neoendorphin analgesia are reversed by the kappa1-selective antagonist, nor-binaltorphimine (norBNI). Antisense mapping the three exons of KOR-1 revealed that probes targeting all three exons blocked U50,488H analgesia, as expected. However, the selectivity profile of dynorphin B and alpha-neoendorphin analgesia towards the various antisense oligodeoxynucleotides differed markedly from U50,488H, implying a different receptor mechanism of action. 相似文献
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The influence of host factors and immunogenetics on lymphocyte responses to Hepagene vaccination 总被引:4,自引:0,他引:4
We have shown that both demographic and immunogenetic factors are involved in the immune responses of Hepagene vaccinated individuals who were persistent nonresponders to 'S' containing hepatitis B vaccines. The HLA-DRB1 0701; DQB1 0202 genotype was found to be associated with a decline of anti-HBs antibodies (anti-HBs) and were frequent in those individuals who remained nonresponders following booster vaccination. Contrary to previously published 'S' vaccination data, Hepagene stimulated T-cell responses showed a lack of correlation with the humoral responses. Limiting dilution analysis demonstrated that the cellular immune response is associated with the kinetics of exposure to Hepagene rather than magnitude of the anti-HBs response. It remains that despite the inclusion of the pre-S proteins 74% nonresponder vaccinated individuals failed to produce > 100 IU/l of anti-HBs. However, these were persistent nonresponders and it was therefore encouraging that two doses of Hepagene did seroconvert (> 10 IU/L) 61% of this difficult group. 相似文献
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This article examines the role of multihospital systems and alliances as "innovation carriers." Drawing upon studies of interpersonal and interorganizational communications networks, the authors suggest how membership in a system or alliance, as well as network characteristics, affects innovation practices in general acute care hospitals. 相似文献
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As many industries face uncertain and changing environments, strategic alliances are rapidly emerging as a vehicle for interorganizational cooperation. Similarly in health care, alliances represent a mechanism for organizations to seek collaborative solutions to common problems. Drawing on a general typology, alliances in health care are categorized as service, opportunistic, or stakeholder alliances. Existing health care alliances serve to illustrate and characterize the purpose, structure, and operation of each of the three types. Strategic alliances offer significant challenges in managing the inherently fragile relationships within these emerging organizational forms. These challenges center around issues of commitment (v. control) as the underlying managerial philosophy; expectations for alliance performance; managing relationships, communication, and operations; member participation in alliance programs and activities; and stability of alliances over time. Alliances require new ways of thinking about organizations. Sensitivity to their unique characteristics and understanding the factors that can lead to their success are essential to managing them effectively. 相似文献