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1.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight. 相似文献
2.
Case-adjusted prospective reimbursement systems, such as resource utilization groups (RUGs), may promote nursing home cost containment, but they may do no better than existing systems at encouraging homes to admit the more dependent and thus costlier Medicaid patients, if the homes' reluctance to admit these patients is due to a shortage of nursing home beds. Using 1983 data on Wisconsin nursing homes, this paper presents evidence that suggests that the presence of excess demand, rather than low reimbursement rates, causes nursing homes to exclude the more costly Medicaid patients. Consequently, to benefit fully from RUGs, it is necessary either to eliminate excess demand (by increasing supply or decreasing demand) or to decide which patients have priority for admission and assign reimbursement payments to these patients that significantly favor these patients. Otherwise, access to nursing home care under RUGs is left to chance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
ME BURGE AM JOSHUA CM McNEIL R HUI MJ BOYER R ABRAHAM 《Asia-Pacific Journal of Clinical Oncology》2005,1(1):47-52
Background: Pemetrexed and cisplatin have recently been shown to significantly improve survival compared with cisplatin alone. However, there are only limited data reflecting teaching hospital experience outside a clinical trial. Pemetrexed has only been available in Australia on a restricted basis since 2002. We reviewed our experience of patients treated on the Australian ‘Special Access Scheme’ at three major thoracic oncology units. Methods: Charts were reviewed for all patients enrolled on the scheme. Data was extracted on age, World Health Organization (WHO) performance status, histology, prior therapy, time from diagnosis to starting pemetrexed, chemotherapy (pemetrexed alone or with a platinum), cycle number, response rate, actuarial progression‐free and overall survival. Doses were cisplatin 75 mg/m2 or carboplatin AUC = 5 and pemetrexed 500 mg/m2 every 21 days. Results: 52 patients (32 male and 20 female) were reviewed. Median age was 58 years and 88% were WHO 0–1. Histology included 54% epithelial, 17% biphasic (epithelial and sarcomatoid) and 21% undefined. The median time from diagnosis to administration of pemetrexed was 145 days. Sixty‐five percent had minimal surgical intervention with video assisted thoracoscopy, pleurodesis and biopsy, while 19% had received prior palliative radiation. Seventy‐one percent were chemotherapy naïve, the remaining 29% having received previous platinum and/or gemcitabine regimens. Twenty‐three percent had pemetrexed alone, 35% in combination with carboplatin and 42% with cisplatin. The median number of cycles was 4 (range 1–13). The response rate was 33%. No toxicity was observed in 20% grade 3–4 toxicity in 10% (majority nausea/vomiting). The median progression‐free and overall survival times from starting pemetrexed were 184 days and 298 days, respectively. Conclusions: Pemetrexed‐based regimens are safe and effective in a community setting in malignant mesothelioma. 相似文献
4.
Rajaram Gopalakrishnan Susan Simonton Michael D Rohrer Ioannis G Koutlas 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(6):773-777
Calcifying epithelial odontogenic tumor (CEOT) is a benign, locally aggressive odontogenic neoplasm characterized by sheets and nests of epithelial cells with deeply eosinophilic or occasionally clear cytoplasm, calcifications, and eosinophilic amorphous material that stains positive for amyloid. Although many cases of CEOT are associated with impacted teeth and occasionally appear radiographically as dentigerous cysts, a true cystic variant has not been previously reported. We report a 15-year-old white male with a large cystic maxillary lesion that filled most of the left maxillary sinus. It deformed the medial wall, the inferior orbital floor, and caused narrowing of the left inferior meatus. Histologically, the cystic lining showed characteristics of CEOT. An intraluminal component that featured histologic characteristics of CEOT was identified during surgery. The lesion was enucleated and the postsurgical course of the patient was uneventful. Because follow-up has been for less than 1 year, a meaningful long-term prognosis cannot be determined at present. However, the patient has not reported any symptoms or signs of recurrence during the follow-up period. 相似文献
5.
Monitoring the performance of the health care delivery system is a public health function that becomes more important as organized delivery systems begin to take control over larger portions of the medical care market. The study reported here illustrates how standard medical care epidemiology can be applied to analysis of health care system performance to aid governmental efforts to monitor new developments in the medical care market. In order to evaluate the efficiency of hospital care delivered in Iowa, age- and sex-adjusted population admission rates for five common procedures were generated for all 99 counties. The five common procedures were defined as follows: hernia, tonsillectomy, cesarean section, hysterectomy, and cholecystectomy. In addition, variations in 11 ambulatory care-sensitive condition rates were analyzed. Residents of at least 15 counties were at significantly greater than average risk of receiving each of the common procedures (chi 2 test, P < 0.05). Counties that had a high rate for one procedure tended to have a high rate for at least one other procedure. Several counties had more than twice the mean rate. Even a 10% reduction, when added across all five common procedures. amounts to well over 2,000 hospitalizations avoided. It is assumed that reductions would be concentrated in high-rate counties. If a 50% reduction could be achieved in only part of the ambulatory care-sensitive procedures, more than 10,000 hospital admissions could be avoided. 相似文献
6.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
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