SEARCH · PubMed Health

Results for “multivariate analysis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources

PubMed1998

[The use of bilateral mammary artery in myocardial revascularization. The risk factors emergent from a multivariate analysis conducted on 474 patients].

BACKGROUND: The internal mammary artery is used as coronary artery graft conduit because of its superior patency. According to some authors, the bilateral IMA can increase perioperative morbidity. The aim of this study was to determine the risk factors increasing perioperative mortality and morbidity in the use of bilateral IMA. METHODS: We analyzed the data of 474 patients operated consecutively with the use of bilateral IMA between January 1987 and December 1995 at the Department of Cardiac Surgery of the Varese Hospital. The univariate analysis was done on 17 ordinal variables using a "Fisher exact test" and on 4 continuous variables by "pooled-variance t-test" to investigate risk factors for mortality, mediastinitis, superficial wound infection and aseptic dehiscence of the sternum; a p-value lower than 0.1 was used as cut-off point to introduce the variables into a stepwise multiple logistic regression analysis. RESULTS: From the univariate analysis are: postoperative low-output syndrome (p = 0.01), LVEF (p = 0.02) and number of grafts (p = 0.04) are correlated to hospital mortality (1.5%); obesity (p < 0.001) and peripheral arteriopathy (p = 0.009) are correlated to postoperative mediastinitis (5%); obesity (p < 0.001), peripheral arteriopathy (p = 0.009), surgeon (p = 0.001), year of operation (p < 0.001), reoperation for bleeding (p = 0.004) and length of extracorporeal circulation (p = 0.02) are correlated to superficial wound infection (7%); obesity (p = 0.002) and COPD (p = 0.05) are correlated to aseptic dehiscence of the sternum (2%). The multivariate analysis identified low LVEF as the only independent risk factor for hospital mortality (p = 0.03), whereas obesity (p = 0.01) and peripheral vasculopathy (p = 0.03) proved to be correlated to postoperative mediastinitis; obesity (p < 0.001), year of the operation (p < 0.001), low LVEF (p = 0.007) and reoperation for bleeding (p = 0.01) were correlated to superficial infection of the wound and obesity turned out to be the only risk factor for aseptic dehiscence for the sternum (p = 0.003). The infection of the wound did not increase mortality, but it did increase the mean postoperative length of hospital stay (6 days for patients free of any complications of the wound versus 29.7 days for patients with complications of the wound). CONCLUSIONS: In patients with bilateral mammary grafts, obesity is the main risk factor for complications of the wound and this event greatly increases the length of the patient's hospital stay. Consequently, we suggest that bilateral mammary artery grafts be used carefully in this subset of patients.

Coronary Disease↗

PubMed1992

Stage IB or IIA-B carcinoma of the intact uterine cervix treated with irradiation: a multivariate analysis.

Although treatment results for Stage IB-IIA-B carcinoma of the cervix are generally stratified only by stage, several authors have found that other parameters such as tumor size, patient age, histology, and pretreatment hematocrit may influence pelvic control and/or survival. This is an analysis of 306 patients with carcinoma of the cervix treated with irradiation alone at the University of Florida between October 1964 and June 1984. Results were analyzed for the end points of pelvic control, distant metastasis, relapse-free survival, and overall survival. Stage for stage, there was a decrease of at least 20 percentage points in pelvic control rates of tumors greater than or equal to 6 cm versus those of tumors 0 to 3 cm in diameter, by univariate analysis; a similar pattern was also observed for the end point of relapse-free survival. When patients were stratified by Stages IB-IIA (greater than or equal to 6 cm and less than 6 cm) and IIB (greater than or equal to 6 and less than 6 cm), there was a clear pattern of improved pelvic control and relapse-free survival for patients over 50 years old and for patients with pretreatment hematocrits greater than 40%. The parameters of stage, tumor size, patient age, histology, and pretreatment hematocrit were evaluated in a multivariate analysis. For the end points of pelvic control, distant metastasis, and relapse-free survival, only tumor size was of independent prognostic significance for all three end points with p-values of 0.022, 0.003, and 0.0006, respectively. Stage did not show independent prognostic significance for any of these end points with p-values of 0.257, 0.878, and 0.284, respectively. The data suggest that tumor size is an important prognostic factor and should be incorporated into the reporting of cervical cancer treatment results.

Adenocarcinoma↗

PubMed1999

[Toward a simplified method of classifying urinary incontinence in the elderly based on a multivariate analysis of 948 cases].

OBJECTIVE: The present study analyzes the main clinical types of urinary incontinence in the elderly population and its clinical-urodynamic correlation to facilitate definitive diagnosis. METHODS/RESULTS: The study was conducted in 948 elderly patients (382 male, 566 female; mean age 72.4 years) with urinary incontinence. Patient clinical and urodynamic records were reviewed. The most common clinical types were urge-incontinence (56.4%) and incontinence with coughing associated with urge-incontinence (32.3%); the latter type was the most common in women. The most frequent urodynamic diagnoses were isolated bladder instability (29.9%), followed by obstruction (15.6%) and stress incontinence (14%). CONCLUSIONS: The most common symptom in bladder instability was urge-incontinence, while incontinence with coughing was found to be the most common symptom in urinary stress incontinence. A significant correlation was found between the postvoid residual urine and the main urodynamic diagnoses. Multivariate analysis showed that classification by clinical types of incontinence together with measurement of residual urine can facilitate diagnosis, although this approach has a low sensitivity for the main forms of isolated incontinence. The mixed forms require a urodynamic study.

Aged↗

PubMed1999

Prognostic factors in metastatic neuroblastoma in patients over 1 year of age treated with high-dose chemotherapy and stem cell transplantation: a multivariate analysis in 218 patients treated in a single institution.

The purpose of this paper is to study prognostic factors in neuroblastoma patients treated with high-dose chemotherapy and hematopoietic stem cell transplantation. Two hundred and eighteen children over 1 year of age and treated for stage 4 neuroblastoma were enrolled in this study. The median age at diagnosis was 39 months, the sex ratio 1.5 and 84% of patients had an abdominal primary tumor. Skeletal disease was detected in 79% of cases and bone marrow involvement in 93%. N-myc oncogene amplification was present in 27% of the patients studied. The probability of event-free survival at 5 years post-diagnosis was 29% in this series. Three major favorable prognostic factors were significant and independent in the multivariate analysis: age under 2 years at diagnosis (P<0.01), absence of bone marrow metastases at diagnosis (P<0.04) and the high-dose conditioning regimen containing busulfanmelphalan combination (P = 0.001). The quality of response to conventional primary chemotherapy was close to significance (P = 0.053). We conclude that factors related to the patient (age) and extent of disease are predictive of outcome in patients with neuroblastoma treated with conventional chemotherapy followed by surgical excision of the primary and consolidation with high-dose chemotherapy. They should be taken into account in future prospective studies. Moreover, the type of conditioning regimen appears to be the most important prognostic factor. This should encourage new investigations into innovative drug combinations.

Adolescent↗

PubMed2002

Multivariate analysis of the prognostic significance of DNA-ploidy and S-phase fraction in ovarian cancer determined by flow cytometry following detection of cytokeratin-labeled tumor cells.

OBJECTIVE: The outcome of patients with advanced ovarian cancer is poor despite aggressive therapy including surgery and multiagent chemotherapy. Valid prognostic factors are necessary to estimate the course of the disease and to define biologically similar subgroups for analysis of therapeutic efficacy. METHODS: This study is the first published prospective study concerning the prognostic significance of DNA-ploidy and S-phase fraction in ovarian cancer following enrichment of tumor cells by cytokeratin labeling. Epithelial cells were labeled by FITC-conjugated cytokeratin antibody (CK 5, 6, 8, and 17) prior to flow cytometric cell cycle analysis in 129 fresh specimens of primary ovarian cancer. RESULTS: Recurrence-free survival of patients with DNA-diploid primary ovarian cancer was significantly better compared to that of patients with DNA-aneuploid tumors in univariate analysis (47% vs 18%, P = 0.01). The tumor-dependent overall survival of patients with DNA-diploid tumors was 57% compared to 30% with DNA-aneuploid tumors (P = 0.04). In FIGO stage III ovarian cancer DNA-ploidy, optimized by cytokeratin gating for tumor cells, achieved independent prognostic significance. No significance was found for S-phase fraction. However, despite convincing methodological advantages in the detection of DNA-aneuploid subpopulations the clinical significance of cytokeratin gating of epithelial cells was only marginal. CONCLUSION: DNA-ploidy has been shown to be as powerful or even more so in comparison to postoperative residual tumor in multivariate analysis for predicting clinical outcome in advanced ovarian cancer. Thus, determination of DNA-ploidy should be introduced to currently recruiting phase III studies for therapy of ovarian cancer for better definition of prognostic subgroups.

Adult↗

PubMed2005

Multivariate analysis of risk factors for feline hyperthyroidism in New Zealand.

AIM: To search for putative risk factors for feline hyperthyroidism in New Zealand, using a case-control study. METHODS: A questionnaire-based case-control study involving the owners of 375 cats in New Zealand (125 hyperthyroid cats, 125 randomly selected control cats, and 125 age- and sex-matched control cats) was conducted to examine associations between potential risk factors and occurrence of feline hyperthyroidism. Data were collected between December 1996 and February 1998, relative to cat and owner demography and medical history, cats' indoor and outdoor environments, and cats' diets. A range of statistical techniques was employed to analyse the data, including descriptive analyses, univariate logistic regression for each variable and multivariate stepwise forward logistic regression. RESULTS: Multivariate analysis revealed that affected cats were more likely to be female (odds ratio (OR)=3.3; 95% confidence interval (CI)=1.2-9.0) and older than unaffected random control cats. Purebred cats were at a much lower risk of being diagnosed as hyperthyroid than were domestic short- and long-haired cats (OR=0.01; 95% CI=0.001-0.20). If more than one cat was present in a household, hyperthyroidism was less likely to be identified (OR=0.15; 95% CI=0.05-0.44) compared with single-cat households. Hyperthyroid cats were 6.6 times more likely (95% CI=1.8-23.9) to be reported to sleep predominantly on the floor than control cats. Cats whose bedding was regularly treated with anti-flea products appeared to be at a considerably higher risk for hyperthyroidism (OR=57.6; 95% CI=3.8-->200); and, to a lesser extent, so were cats living in households where fly sprays were reported to be used regularly (OR=3.3; 95% CI=1.2-9.3). The interaction between drinking water from puddles and regular use of organic garden fertilisers, such as compost or animal manure, was associated with a 5.3-fold (95% CI=1.1-25.6) increase in the risk of cats being diagnosed with the disease. Hyperthyroid cats were twice as likely (95% CI=0.3-12.9) to have eaten at least half of their daily food requirements as canned commercial cat food compared with unaffected cats. Cats exposed to a variety of flavours of canned cat food were more likely to be diagnosed with hyperthyroidism than were those fed only one flavour (OR=3.8; 95% CI=1.5-9.6). The presence of dental disorders was associated with a 5.5-fold increase in the risk of being diagnosed as hyperthyroid and this association was independent of the cat's age (95% CI=1.7-17.5). CONCLUSIONS: The results of this study support and extend those in several earlier reports and show that cats in New Zealand are, in many respects, similar to cats in Europe and North America in terms of their susceptibility to hyperthyroidism. The finding that female cats are predisposed to hyperthyroidism is at variance with most previously published work. It remains unclear which, if any, of the identified disease associations are causal, so further studies of this increasingly prevalent feline endocrinopathy are warranted.

Animals↗

PubMed1997

[Predictive factors of coronary restenosis after optimal directional atherectomy. A multivariate analysis apropos of 102 patients].

The authors studied 102 patients prospectively who were undergoing coronary atherectomy optimised by balloon dilatation in order to assess the restenosis rate at 6 months. The coronary lesions were measured in a reproducible manner by quantitative angiography. The vessels dilated were the left anterior descending in 66 patients and the right coronary artery in 36 patients. The reference diameter was on average of 3.57 +/- 0.64 mm. Atherectomy increased the minimal diameter of the lesion of 1.20 +/- 0.44 to 3.01 +/- 0.44 mm giving a residual stenosis of 15 +/- 11%. At six months, 25% of patients had developed a restenosis (> 50% stenosis) with a residual lumen of 2.15 +/- 0.77 mm. The predictive factors of restenosis were the initial absolute gain, the length of the lesion, the reference diameter of the vessel and the presence of an endoluminal thrombus. In multivariate analysis, a small initial gain (p < 0.02) and length of stenosis (p < 0.02) were independently correlated with restenosis. The authors conclude: 1) that optimal atherectomy is associated with acceptable restenosis rates in selected vessels, 2) that short stenoses of large diameter arteries may be a privileged indication of the technique if the best results are obtained.

Adult↗

PubMed1993

[Multivariate analysis of mandibular morphology with fetal growth by means of the soft standardized radiographs].

Mandibular growth of the fetus is a great matter of importance to anatomy, anthropology and also oral and Maxillofacial surgery. The postnatal changes of the mandible that have occurred with growth have been reported by numerous investigators. However, a few researchers have investigated the prenatal growth of the mandible. The purposes of this study were discussed how to change in size and shape of the mandible during the fetal period. The materials consisted of 162 human fetuses from the body length (BL) of 95 mm, to 500 mm. They were divided into four groups: 95-199 mm (BL1, N = 40), 200-299 mm (BL2, N = 76), 300-399 mm (BL3, N = 26), 400-500 mm (BL4, N = 20). All specimens were stored in formalin, and only those free from gross deformation were selected for study. The heads were removed by decapitation at the level of the hyoid bone. The soft standardized radiographs were taken of the frontal, lateral, basal aspects. They were used for tracing and angular and linear measurements (total thirty). The data were used to evaluate the mandibular form by multivariate analysis. They were supported the univariate analysis. The findings leads to the following conclusions: 1) Cluster analysis and principal component analysis were applied to the data to make clear the correlation between 30 variables. Four clusters were constructed at the level ninety similarities in cluster analysis. They were corresponded to four factors were obtained in principal component analysis. 2) The data were subjected to a stepwise discriminant function analysis using the seventeen of original 30 variables. Nine variables, mandibular length (Go-Me), mandibular ramus height (Col-Go), Symphyseal height (Id-Me), mandibular body height (Kr'-beta), gonial angle (< Co2, Go, Me), mental angle (< Id, Pog, Go), gonial width (BGo), alveolar width (BKr'), basal angle of mandible (< RGo, Me, LGo), were selected as the best discriminators. The incidence of correctly classified cases 88.68%. 3) As a result of the first discriminant function of the discriminant analysis and one-way analysis of variance (ANOVA) and t-test, mandibular length (Go-Me), gonial width (BGo), alveolar width (BKr'), Symphyseal height (Id-Me) were longer in tall group that short group (BL4 > BL3 > BL2 > BL1). Therefore, the first discriminant function was accounted for the size factor. 4) In consequence of the second discriminant function of the discriminant analysis and regression analysis, gonial width (BGo) was grown broader than alveolar width (BKr') from BL1 to BL2.(ABSTRACT TRUNCATED AT 400 WORDS)

Anthropometry↗

PubMed2004

Prognosis of traumatic head injury in South Tunisia: a multivariate analysis of 437 cases.

BACKGROUND: This study aimed to determine predictive factors of mortality after posttraumatic brain injury. METHODS: A retrospective study conducted over a 3-year period (1997-1999) involved 437 adult patients with head injury admitted to the intensive care unit of a university hospital in Sfax, Tunisia. Basic demographic, clinical, biologic, and radiologic data were recorded at admission and during the intensive care unit stay. RESULTS: This study included 393 men (90%) and 44 women with a mean age of 36 +/- 17 years. Traffic accidents were the main cause of trauma (85.6%). In 58% of the cases, the injury was serious (Glasgow Coma Score, <8). The mean simplified acute physiology score was 39 +/- 15, and the mean Injury Severity Score was 34.5 +/- 17. Of the 437 patients, 127 (29.1%) died. According to multivariate analysis, the factors that correlated with a poor prognosis were age older than 40 years (p < 0.01), simplified acute physiology score exceeding 40 (p < 0.001), Glasgow Coma Score lower than 7 (p = 0.03), intracranial mass lesion (p = 0.02), a cerebral herniation (p < 0.001), diabetes insipidus (p < 0.001), and blood sugar level higher than 10 mmol/L (p < 0. 001). CONCLUSIONS: In Tunisia, head injury is a frequent cause of hospitalization, comprising 14.4% of all adult admissions. It is observed most often among young patients involved in traffic accidents. The short-term prognosis is poor, with a high (29%) mortality rate, and determined by demographic, clinical, radiologic, and biologic factors. Prevention is highly advised.

Accidents, Traffic↗

PubMed2002

Late recurrence in 1263 men with testicular germ cell tumors. Multivariate analysis of risk factors and implications for management.

BACKGROUND: Testicular germ cell tumors are highly curable. However, 10-30% of patients have recurrence after initial treatment. The time-course of recurrence has implications for the duration of follow-up. This study was undertaken to assess the risk and time-course of recurrence and to identify patients at higher risk of late recurrence. METHODS: The records of 1263 patients with primary testicular germ cell tumors presenting to the Royal Marsden Hospital between December 1979 and December 1993 were reviewed. In all, 255 episodes of recurrence were documented (including 44 patients with multiple recurrences) and used to calculate recurrence-free survivals. RESULTS: Fifty-three patients (15 seminomas; 38 nonseminomatous germ cell tumors [NSGCT]) had recurrence more than 2 years after initial presentation. A multivariate analysis of risk of recurrence after 2 years identified positive markers at presentation and the presence of differentiated teratomas in postchemotherapy surgical specimens as significant predictors. Very late recurrence (> 5 years) occurred mainly in patients with metastatic NSGCT (12 of 14 patients) with a 1% annual risk of recurrence between 5 and 10 years. Very late recurrence was also seen in one case of metastatic seminoma and one case of Stage I NSGCT managed by surveillance. Most late recurrences (n = 9) were detected at routine annual follow-up visits but five had recurrences with symptoms leading to an unscheduled clinic visit. CONCLUSION: Late recurrences are rare in patients with testicular germ cell tumors and follow-up to detect recurrence may not be needed after 5 years, except in those presenting with metastatic NSGCTs.

Adolescent↗

PubMedDate not supplied

Prognosis of patients with gastric carcinoma treated in remote island hospitals in Japan: a multivariable analysis.

BACKGROUND: Treating gastric cancer in remote island hospitals remains a major clinical challenge. Factors affecting prognosis of patients treated in general hospitals are still at large. We sought to determine the characteristics of gastric cancer in the Amamiooshima (Amami) archipelago of Japan and also evaluated the independent prognostic factors by the Cox regression analysis. MATERIALS AND METHODS: A total of 125 patients treated in four sister hospitals in the Amami were analyzed. RESULTS: The median age of patients with resection was 74 years and almost 85% patients had diffuse type of cancer. The 5-year overall survival was 34% for all patients and 58% for those who had a resection. Among the several clinicopathological factors, operation method (distal vs. total gastrectomy), splenectomy, lymphatic and venous invasion, T-stage, metastatic lymph node (MLN) size n-stage and UICC N-stage had significant impact on survival. Only MLN size and intraoperative blood loss had independent effect on survival by multivariable analysis. CONCLUSION: Improved perioperative care may yield a reasonable patient survival in elderly patients with gastric carcinoma treated in remote hospitals. Restricting amount of intraoperative blood loss may further improve the patient prognosis and MLN size may serve as a new metric to stage gastric cancers.

Adult↗

PubMed2002

Prognosis of hepatic cirrhosis patients with esophageal or gastric variceal hemorrhage: multivariate analysis.

OBJECTIVE: To study the effect of bacterial infection, use of antibiotics, active bleeding at endoscopy, and the severity of liver disease as prognostic factors in hepatic cirrhotic patients during the first 5 days after the episode of esophageal or gastric variceal hemorrhage. METHODS: Seventy-six hepatic cirrhosis patients with esophageal or gastric variceal bleeding were enrolled. Bleeding was managed in a standardized protocol using octreotide and vasopressin in sclerotherapy or band ligation for active bleeding at endoscopy. The screening protocol for bacterial infection consisted of chest radiograph; blood, urine and ascitic fluid cultures; the severity of liver disease shown by Child-Pugh score. RESULTS: Active bleeding was observed at endoscopy in 40 patients (53%). Failure to control bleeding within 5 days occurred in 36 patients (45%). Empirical antibiotic treatment was used in 53 patients (67%), whereas bacterial infections were documented in 43 patients (57%). Multivariate analysis showed that proven bacterial infection (P<0.01) or antibiotic use (P<0.05) as well as active bleeding at endoscopy (P<0.01) and Child-Pugh score (P<0.01) were independent prognostic factors of failure to control bleeding. CONCLUSION: Bacterial infection is associated with failure to control esophageal or gastric variceal bleeding in hepatic cirrhotic patients.

Bacterial Infections↗

PubMed1993

T1-T2 squamous cell carcinoma of the glottic larynx treated with radiotherapy: a multivariate analysis of variables potentially influencing local control.

PURPOSE: To examine various parameters that might influence the probability of local control of T1-T2 glottic carcinoma treated with radiotherapy. METHODS AND MATERIALS: Two hundred forty-seven patients with invasive, previously untreated T1-T2 squamous cell carcinoma of the glottic larynx were treated with radiotherapy between May 1977 and December 1989. All patients had a minimum 2-year follow-up. To minimize treatment-related variables, only patients with T1 lesions treated once daily at 225 cGy per fraction and patients with T2 lesions treated once daily at 225 cGy per fraction or twice daily at 120 cGy per fraction were included. Surgical alternative, thickness of the neck at the posterior edge of the lateral fields, vocal cord mobility, anterior commissure involvement, gender, and T stage were evaluated in a multivariate analysis. RESULTS: The 5-year local control rates, calculated by the product-limit method, were T1a, 95%; T1b, 96%; T2a, 87%; and T2b, 76%. The 5-year local control rate for patients with T2 lesions treated with once-daily fractionation was 81% compared with 91% for those who received twice-a-day radiotherapy. For the endpoint of local control with irradiation, the surgical alternative (p = .020) and cord mobility (p = .001) were of independent prognostic significance. CONCLUSION: Of the variables analyzed, only vocal cord mobility and surgical alternative significantly influenced local control. Specifically, anterior commissure involvement and neck thickness did not affect local control.

Carcinoma, Squamous Cell↗

PubMed1994

Pre- and postoperative carcinoembryonic antigen determinations in hepatic resection for colorectal metastases. Predictive value and implications for adjuvant treatment based on multivariate analysis.

OBJECTIVE: The object of this study was to evaluate the prognostic significance of pre- and postoperative serum carcinoembryonic antigen (CEA) levels in the resectional treatment of colorectal hepatic metastases. The main question was whether postoperative CEA levels correlated with survival and the time to recurrence. SUMMARY BACKGROUND DATA: Despite numerous investigations on prognostic factors in colorectal cancer, only sparse data are available to estimate the patient's individual risk for tumor recurrence postoperatively. It is controversial whether preoperative CEA values are of prognostic significance, and after observing the kinetics of CEA decline, elevated CEA levels postoperatively were found to be an ominous sign. CEA therefore could indicate the presence of a tumor burden after resection. METHODS: One hundred sixty-six patients undergoing hepatic resection for colorectal metastases with curative intent were prospectively documented and underwent multivariate analysis for indicators of prognosis. RESULTS: Abnormal preoperative CEA levels were not of prognostic significance compared with values within the normal range (survival, 36 vs. 30 months; p = 0.12; disease-free survival, 12 vs. 10 months; p = 0.82). The postoperative serum CEA level, however, was the most predictive factor with regard to survival and the disease-free interval. Patients in whom CEA levels were abnormal before surgery and returned into the normal range after resection had significantly better survival times (37 vs. 23 months, p = 0.0001) and disease-free survival times (12 vs. 6.2 months, p = 0.0001) compared with patients with persistently abnormal values. CONCLUSIONS: Pre- and postoperative determination of the serum CEA level is mandatory to judge whether a curative resection has been performed and whether tumor has been left behind after the operation. Postoperative CEA levels also should be used as a stratification criterion in adjuvant treatment studies after hepatic resection to indicate patients with a high risk of tumor recurrence.

Adult↗

PubMed2006

Assessing heavy metal sources in agricultural soils of an European Mediterranean area by multivariate analysis.

According to the European Thematic Strategy for Soil Protection, the characterization of the content and source of heavy metals in soils are necessary to establish quality standards on a regional level that allow the detection of sampling sites affected by pollution. In relation to this, the surface horizons of 54 agricultural soils under vegetable crops in the Alicante province (Spain), a representative area of the European Mediterranean region, were sampled to determine the content of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Analytical determinations were performed by atomic absorption spectroscopy after microwave sample digestion in acid solution. Results indicated that heavy metal levels were similar to those reported by authors working on agricultural soils from other parts of the Mediterranean region, with the exception of Cu and Pb in some samples. Multivariate analysis (principal component analysis and cluster analysis) was performed to identify a common source for heavy metals. Moreover, soil properties were determined in order to characterize agricultural soils and to analyze relationships between heavy metal contents and soil properties. The content of Co, Cr, Fe, Mn, Ni and Zn were associated with parent rocks and corresponded to the first principal component called the lithogenic component. A significant correlation was found between lithogenic metals and some soil properties such as soil organic matter, clay content, and carbonates, indicating an important interaction among them. On the other hand, elements such as Cd, Cu and Pb were related to anthropic activities and comprised the second (Cu and Pb) and third principal components (Cd), designated the anthropogenic components. Generally, Cd, Cu and Pb showed a lower correlation with soil properties due to the fact that they remain in available forms in these agricultural soils. Taking into account these results and other achieved in other parts of the European Mediterranean region, it can be concluded that soil quality standards are highly needed to declare soils affected by human induced pollution. This is particularly relevant for anthropogenic metals (Cd, Cu and Pb, and in some areas also Zn). Further research in other agricultural areas of the region would improve the basis for proposing such soil quality standards.

Agriculture↗

PubMed1997

Quality assessment of perinatal regionalization by multivariate analysis: Illinois, 1991-1993.

OBJECTIVE: To identify (1) those elements in the infrastructure of a regionalized perinatal network that have independent effects on the variation in perinatal mortality among nontertiary units (member level I and II hospitals) and (2) shortcomings, if any, in a traditional perinatal data base that impede quality assessment of contemporary regionalized care. METHODS: We analyzed perinatal surveillance data for 3 years, from 1991 to 1993, in the state of Illinois, representing more than 190,000 annual births. Fetal death and neonatal mortality rates for the 97 nontertiary hospitals studied were the dependent variables of interest. Two sets of independent variables were studied, those assessing the maternal sociobehavioral risk of populations served and those assessing the network infrastructure (defined as the facilities of member hospitals and their function within the regionalized network). We used multivariate analysis to partition the variation in hospital rates of perinatal mortality into two components, one attributable to maternal sociobehavioral risk and the other to the network infrastructure. RESULTS: Maternal sociobehavioral risk alone explained 73% of the variation in hospital fetal death rates and 38% of that in hospital neonatal mortality rates. When controlling for maternal sociobehavioral risk, rates of inborn very low birth weight (VLBW) deliveries (P < .001) and neonatal transport (P = .01) had independent effects on the variation in hospital fetal death rate; rates of inborn VLBW deliveries (P < .001), neonatal transport (P < .001), and proportion of VLBW infants transported out (P = .029) had independent effects on the variation in hospital neonatal mortality rate. CONCLUSIONS: In this mature statewide network, the rate of inborn VLBW deliveries exerted the strongest independent effect on variation in level I and II hospital rates of both fetal death and neonatal mortality. However, that there was such a large effect from maternal sociobehavioral risk alone has important public health implications. Additions and modifications to traditional perinatal surveillance are suggested better to assess the quality of regionalization in a contemporary health care environment.

Databases, Factual↗

PubMed2001

Multivariate analysis of factors influencing quality of life and utility in patients with haemophilia.

BACKGROUND AND OBJECTIVES: Although several studies have determined quality of life (QOL) in patients with hemophilia, generic questionnaires have rarely been used. The objectives of our study were; 1) to measure QOL and utility in patients with hemophilia using the Short Form 36 (SF-36) and the EuroQOL questionnaires; 2) to evaluate the influence of some clinical variables on QOL and utility; 3) to assess the correlation between the two questionnaires. DESIGN AND METHODS: All consecutive patients with hemophilia were asked to complete the SF-36 and the EuroQOL questionnaires. The following information was recorded from each patient: age, type of hemophilia, severity of disease, HCV and HIV infection, number of bleeding episodes and cumulative dose of coagulation factors over the previous year. These items were entered into a multivariate analysis to assess their effect on QOL. Correlation analyses were conducted to evaluate the relationship between the EuroQOL and SF-36. RESULTS: Fifty-six patients completed the SF-36 and the EuroQOL questionnaires. The mean scores of the SF-36 ranged from 55.2 (general health) to 74.7 (social functioning). The EuroQOLself-classifier and the EuroQOLvas showed a mean score of 0.67 (SD=0.26) and 0.66 (SD=0.17), respectively. Among the clinical variables, age significantly influenced both the EuroQOL and the SF-36 scores. The EuroQOL indices showed a statistically significant correlation with each dimension of the SF-36. INTERPRETATION AND CONCLUSIONS: Our study quantified the degree to which QOL is impaired in patients with hemophilia by using both a generic questionnaire and a utility-based approach.

Adult↗

PubMed1993

Multivariate analysis of magnetic resonance imaging of focal hepatic lesions.

A total of 124 lesions from 1 to 6cm in diameter, including 31 cavernous hemangiomas, 32 metastases and 61 hepatocellular carcinomas (HCC) were analyzed to study the usefulness of magnetic resonance imaging (MRI) at 0.5 Tesla to differentiate focal hepatic lesions on the basis of qualitative criteria. Each focal hepatic lesion was assessed for shape, internal architecture and signal intensity relative to normal liver parenchyma. While all cavernous hemangiomas and metastases except one lesion could be detected, detection rate of HCC was significantly inferior to that of the other two diseases. A tumor capsule and a hyperintense focus on T1-weighted images were demonstrated in only HCC lesions in strong contrast with the other two diseases; however, metastases with slow-growing characteristics or subacute hematoma may appear as similar images. Cavernous hemangiomas appeared markedly hyperintense on T2-weighted images in 23 of 31 lesions, but one metastasis and one HCC had similar images. A multivariate analysis of several MRI resulted in the following mean discriminant scores: cavernous hemangioma, -1.2652; metastasis, 0.1830; and HCC, 0.7138. It appeared to be possible to differentiate the three diseases with 84.4 percent accuracy.

Adult↗