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991.
Cost-efficiency targets, used to encourage downward pressure on hospital unit costs, have been employed within the UK NHS for many years. There has been considerable speculation that these targets create incentives to reduce beds and increase occupancy rates at the expense of holding spare capacity to accommodate fluctuations in emergency admissions. This research used panel data for the period 1994/1995-1999/2000, supplemented by a series of semi-structured interviews, to explore the strategies Trusts employ to reduce unit costs. No relationship could be found between published targets and changes in unit costs, nor that targets were successful in reducing the dispersion of unit costs over time. Interviews revealed that efficiency gains required of Trusts, usually dictated by the local health economy, often bore no correspondence to the national or regional published targets. Results further indicated that contrary to prior speculation, Trusts divide into two distinct groups, those with high occupancy rates and those with a high proportion of free beds to accommodate emergencies, with Trust characteristics displaying stability over time. A pressing need for future work is the development of measures to encourage efficiency that take account of quality improvement. 相似文献
992.
Pahwa P McDuffie HH Dosman JA Robson D McLaughlin JR Spinelli JJ Fincham S 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2003,45(8):857-868
Exposures to farm animals has been associated with certain rare cancers. Simultaneously, using the same methodology and control group, we conducted a six-province incident, population-based study of Hodgkin's disease (HD), multiple myeloma (MM), and soft tissue sarcoma (STS). Farm residence or work was reported by 38% (n = 119) of HD, 45% (n = 178) of MM, 43% (n = 156) of STS cases and 45% (n = 673) of controls. We conducted conditional logistic regression analyses and report odds ratios (OR(adj)) and 95% confidence intervals. After adjustment for covariates, exposure to farm animals had minimal effect on risk. The independent risk factors after adjustment for covariates were a family history of cancer (MM, STS), occupational uranium exposure (HD), professional driving (MM), and personal previous cancer (MM) or shingles (HD, MM). 相似文献
993.
994.
OBJECTIVES: In England, the Department of Health places high priority on reducing the variation in unit costs of National Health Service (NHS) hospitals. Efficiency targets are set for hospitals to create incentives for relatively high cost hospitals to reduce their costs and shift performance closer to that of their lower cost counterparts. We examine empirically the dispersion in unit costs to assess the extent of variation in the productivity of hospitals and trends over time. METHODS: We use econometric panel data techniques on data from 235 NHS acute hospital trusts over a six-year period, 1994/95 to 1999/00, supplemented with information from semi-structured interviews with key individuals in hospitals and purchasing bodies. RESULTS: There appears to have been no reduction in variation during this period. Relative unit costs for individual trusts also appear stable, with little movement from relatively high cost to low cost. Judging from limited quantitative evidence outside health care, the variation in costs between NHS hospitals may be comparatively low. CONCLUSIONS: Given all the other aspects of hospital performance that government is seeking to change, reduction in the dispersion of unit costs per se should not be a major policy objective. It is far more important to examine variation in quality-adjusted unit costs. 相似文献
995.
OBJECTIVE: There are few analytical results that describe patient compliance with drug administration regimens. The purpose of this paper is to develop and assess stochastic approaches for mathematical modelling of patient compliance with administration regimens. METHODS: Two stochastic models based on Markov-dependent random variables and on the Ising model were assessed for their ability to describe the variable nature of drug compliance. RESULTS: Both models use only experimentally accessible data, and their predictions were tested against published clinical compliance data obtained from electronic monitoring devices. The models satisfactorily fitted administration interval distribution data from several patients treated with diltiazem, a calcium channel antagonist, or zidovudine, an antiretroviral agent. The Ising model provides additional analytical expressions for the distribution of success runs and 'drug holidays' in administration regimens. These distribution predictions were tested with success run data for diltiazem and drug holiday data for two nonsteroidal anti-inflammatory drugs, piroxicam and tenoxicam. CONCLUSIONS: Stochastic models can provide useful insights into drug compliance, and can be used to identify the administration patterns that are more likely to occur during drug self-administration in populations. 相似文献
996.
Soria JC Moon C Kemp BL Liu DD Feng L Tang X Chang YS Mao L Khuri FR 《Clinical cancer research》2003,9(5):1785-1791
PURPOSE: Interleukin-10 (IL-10) may play an important role in controlling tumor growth and metastasis. Some reports have shown that IL-10 can be a potent inhibitor of tumor growth, but others suggest that IL-10 expression by the tumor is an adverse prognostic factor. Because normal bronchial epithelial cells constitutively produce IL-10, we decided to test the prognostic value of IL-10 in a well-defined population of patients with stage I non-small cell lung cancer (NSCLC) treated in a single institution. PATIENTS AND METHODS: Using immunohistochemical analysis, we retrospectively analyzed IL-10 expression in specimens from 138 patients with completely resected clinical/radiographic stage I NSCLC for whom clinical follow-up data were available. RESULTS: IL-10 expression was retained (IL-10 labeling index > or = 10%) in 94 patients (68.1%) and lost in 44 patients (31.9%). The duration of overall, disease-specific, and disease-free survival in the 44 patients lacking IL-10 expression was worse than in the 94 patients with IL-10 expression (P = 0.08, 0.02, and 0.05, respectively; Log-rank test). Interestingly, IL-10 expression was observed more frequently in tumors with squamous cell histology than in tumors of other histological subtypes (P = 0.04; chi(2) test). Multivariate analysis confirmed the independent prognostic value of IL-10 expression for disease-specific survival (P = 0.04). CONCLUSION: Lack of IL-10 expression by the tumor was associated with a significantly worse outcome of early stage NSCLC. The mechanisms underlying this clinically and biologically important finding need to be further explored. 相似文献
997.
Metastatic disease remains a significant contributor to morbidity and mortality in patients with breast cancer. An improved molecular and biochemical understanding of the metastatic process is expected to fuel the development of new therapeutic approaches. The suppression of tumor metastasis, despite tumor cell expression of oncogenes and metastasis-promoting events, has become a diverse and fruitful field of investigation. Although many genetic events promote metastasis, several genes show relatively reduced expression levels in metastatic tumor cells in mouse model systems and in aggressive human tumors. Re-expression of a metastasis-suppressor gene in a metastatic tumor cell line results in a significant reduction in metastatic behavior in vivo with no effect on tumorigenicity. The known metastasis-suppressor gene products nm23, KAI1, mitogen-activated protein kinase kinase 4, breast cancer metastasis suppressor-1, KiSS1, RHOGDI2, CRSP3, and vitamin D3-upregulated protein/thioredoxin interacting protein exhibit unexpected biochemical functions that have shed new light on signaling events that are important in metastasis. Most metastasis suppressors function at the translationally important stage of outgrowth of micrometastatic tumor cells at a distant site. We hypothesize that elevation of metastasis suppressor gene expression in micrometastatic tumor cells in the adjuvant high-risk population of patients with breast cancer will halt metastatic colonization and have a clinical benefit. DNA methylation inhibitors have shown limited promise in increasing metastasis-suppressor gene expression, and ligands of the nuclear hormone receptor family are currently under investigation in vitro and in vivo. Clinical testing of agents that increase metastasis-suppressor gene expression is expected to require tailored trial designs. 相似文献
998.
999.
Carney RM Blumenthal JA Catellier D Freedland KE Berkman LF Watkins LL Czajkowski SM Hayano J Jaffe AS 《The American journal of cardiology》2003,92(11):1277-1281
The ENRICHD clinical trial, which compared an intervention for depression and social isolation to usual care, failed to decrease the rate of mortality and recurrent acute myocardial infarction (AMI) in post-AMI patients. One explanation for this is that depression was not associated with increased mortality in these patients. The purpose of this study was to determine if depression was associated with an increased risk of mortality in a subsample of the ENRICHD trial's depressed patients compared with a group of nondepressed patients recruited for an ancillary study. Three hundred fifty-eight depressed patients with an acute AMI from the ENRICHD clinical trial and 408 nondepressed patients who met the ENRICHD medical inclusion criteria were followed for up to 30 months. There were 47 deaths (6.1%) and 57 nonfatal AMIs (7.4%). After adjusting for other risk factors, depressed patients were at higher risk for all-cause mortality (hazard ratio 2.4, 95% confidence interval 1.2 to 4.7) but not for nonfatal recurrent infarction (hazard ratio 1.2, 95% confidence interval 0.7 to 2.0) compared with nondepressed patients. In conclusion, depression was an independent risk factor for death after AMI, but it did not have a significant effect on mortality until nearly 12 months after the acute event, nor did it predict nonfatal recurrent infarction. 相似文献
1000.
Kelly KD Pickett W Yiannakoulias N Rowe BH Schopflocher DP Svenson L Voaklander DC Kelly KD 《Age and ageing》2003,32(5):503-509
BACKGROUND: The association between injurious falls requiring a visit to the emergency department and various classes of medications was examined in a case-control study of community living persons aged 66 years and older. METHODS: Administrative databases from an urban health region provided the information used. Five controls for each case were randomly selected from community dwelling older persons who had not reported an injurious fall to one of the six regional emergency departments in the study year. Two series of analyses on medication use within 30 days of the fall were conducted using logistic regression, the first controlling for age, sex, and median income, the second controlling for co-morbid diagnoses as well. RESULTS: During the study year there were 2,405 falls reported by 2,278 individuals to six regional emergency departments giving a crude fall rate of 31.6 per 1,000 population per year. The initial analysis identified seven medication classes that were associated with an increased risk of an injurious fall, while controlling for age, gender and income. However, with further analyses controlling for the additional effects of co-morbid disease, narcotic pain-killers (odds ratio 1.68), anti-convulsants (odds ratio 1.51) and anti-depressants (odds ratio 1.46) were significant independent predictors of sustaining an injurious fall. CONCLUSION: These results are based on a Canadian population-based study with a large community sample. The study found that taking certain medications were independent predictors of sustaining an injurious fall in our elderly population - in addition to the risk associated with their medical condition. 相似文献