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PubMed2004

Survival and recurrence after a sphincter-saving resection and abdominoperineal resection for adenocarcinoma of the rectum at or below the peritoneal reflection: a multivariate analysis.

PURPOSE: The purpose of this study was to determine whether the type of operation [sphincter-saving resection (SSR) or abdominoperineal resection (APR)] for primary adenocarcinoma of the rectum at or below the peritoneal reflection affects survival and recurrence after curative surgery. METHODS: This retrospective study included 184 patients who underwent curative surgery achieved by the following two types of operation between 1989 and 1998: (1) SSR ( n = 116 patients) including a low anterior resection with either double-stapling technique ( n = 86) or transanal coloanal anastomosis ( n = 30); (2) APR ( n = 91). The outcome factors evaluated were survival and tumor recurrence. Both univariate and corrected (multivariate Cox's and logistic regression) analyses were used to evaluate the data. The median follow-up was 47.4 months for patients alive at study conclusion. RESULTS: Disease-free and disease-specific survivals, and the frequency and location of recurrence after surgery did not differ between the two types of operations. Multivariate analyses showed that the type of operation was not a significant independent variable in predicting disease-free survival or in the development of both local and distant recurrences after surgery. In addition, tumor-related factors (stage or histologic grade) were significant predictors of the outcome after surgery. CONCLUSIONS: The type of operation (SSR or APR) did not affect the survival or recurrence after a curative resection for adenocarcinoma of the rectum at or below the peritoneal reflection.

Abdomen↗
PubMed1989

Predictors of language restitution following stroke: a multivariate analysis.

A consecutive sample of 50 language-impaired patients was evaluated prospectively during the first 3 to 4 months following unilateral left- or right-hemisphere stroke. A multiple logistic linear regression model was used to assess the relative importance of eight predictor variables on the likelihood of language recovery. Those found to be significantly associated with language recovery included age (favoring younger patients) and length of hospital stay (favoring shorter stays). Gender (favoring males), type of stroke (favoring hemorrhages), and side of lesion (favoring right) were only moderate correlates of recovery. Neither race nor history of previous stroke was a significant predictor of language recovery. Multivariate statistical analysis was useful in illuminating the joint relationship between clinical and demographic predictor variables and language recovery.

Age Factors↗
PubMed2005

Prognostic factors for mesenteric infarction: multivariate analysis of 187 patients with regard to patient age.

Between 1980 and 2002 a total of 187 patients (105 women, 82 men) with a mean age of 71.5 years underwent surgery for acute mesenteric infarction (AMI) in our department. Arterial occlusion was found in 140 patients, splanchnic vein thrombosis in 22, and nonocclusive AMI in 25. We performed bowel resection in 61 patients, vascular surgery in 32, a combination of the two in 15, and an exploratory laparotomy in 79. The mortality rate was 70.6% (73.9% in patients >70 years and 65.2% in those <70). AMI is still a disease with a consistently high mortality rate (60-80%). Multivariate prognostic factors include the time until surgery and a markedly elevated white blood cell count and serum lactate level. Mortality and secondary disease rates are higher in the elderly, and the fact that they have to wait much longer for an operation than younger patients may be a factor. If surgery is performed early, the survival rate increases regardless of age. The most important prognostic factor and the only one that can be influenced by the surgeon remains the time interval between the onset of symptoms and surgery, Therefore diagnostic and therapeutic intervention should be performed as early as possible in patients with suspected AMI.

Adult↗
PubMed2003

Evaluation of different formulation studies on air-filled polymeric microcapsules by multivariate analysis.

Air-filled polymeric microcapsules have been prepared by freeze-drying of emulsions containing the wall-forming polymer in the organic phase of oil in water emulsions. Echogenic air-filled microcapsules were prepared from emulsions containing either (-)-camphene, cyclohexane or cyclooctane as the solvent in the organic phase. Formulation studies have been performed to improve the yield and acoustic quality of the microcapsule suspensions. The yield was measured as particle concentration or efficacy, i.e. normalised attenuation at 3.5 MHz, related to the amount of polymer used. No overall conclusion could be made for all the variables when visually comparing the results from the different investigations. Multivariate analyses (PCA and PLS) were therefore necessary to be able to reveal any relevant systematic information from all the investigations. Different parameters describing the formulation, the production process and parameters describing the characterisation of the intermediates and the final product were set as independent X-variables. Three to four percent (w/v) of polymer was found to be the appropriate concentration of wall forming polymer. Including PEG 3000 resulted in improved freeze-dried product and suspension. Quenching of the emulsions by freezing in dry ice/methanol prior to freeze-drying was not necessary. Process parameters for homogenising and freeze-drying should be optimised with regard to the single systems, due to the different physico-chemical properties of the different solvents, especially melting point and vapour pressure.

Air↗
PubMed1994

Quantitative morphology of human cirrhotic livers. Part II: The statistically adequate morphological classification of liver cirrhosis. Multivariate analysis from quantified data of form.

In a previous report, we developed methods by which to quantify various patterns of cirrhosis. A set of parameters were used: (i) the mean nodular radius; (ii) the coarseness; (iii) the mean septal thickness; and (iv) the degree of nodular separation. This was applied to 70 cirrhotic livers in an attempt to establish a reproducible classification, and the data were subjected to four-dimensional cluster analysis (Ward method) using a mainframe computer. Five clusters appeared: cluster A, fine nodules, thin septa; cluster B, coarse nodules, relatively thin septa; cluster C, fine nodules, thick septa; cluster D, extremely coarse nodules; and cluster E, coarse nodules, thin septa and incomplete nodulation. Of these, cluster A was considered to correspond to the nutritional type of Gall, cluster B to posthepatitic type (Nagayo's Type B), cluster C to postnecrotic type (Nagayo's Type A) and cluster E to the subtype of posthepatitic cirrhosis with incomplete nodulation (Miyake's Type BI). Cluster D comprised cases with extremely coarsened nodules. The reproducibility of this clustering was fully ensured by linear discriminant analysis. Another discriminant analysis, the canonical, allowed us to visualize the separation of clusters in a two-dimensional (2-D) scatter diagram. We thus managed to establish a most adequate classification from a geometric and statistical point of view.

Humans↗
PubMed2006

Multivariate analysis of the selected metals in the hair of cerebral palsy patients versus controls.

Seventeen metals were measured in scalp hair samples from cerebral palsy patients (CPPs) and controls. Samples were collected from 95 CPPs and 93 controls. The nitric acid-perchloric acid wet digestion procedure was used for quantification of the selected metals by flame atomic absorption spectrophotometry. The concentrations of Ag, Ca, Cd, Co, Cr, Li, and Mg were significantly higher and those of Cu, Fe, K, Mn, Na, Ni, Pb, and Sb were lower in the hair of CPPs compared with controls. Astrong positive correlation was found between Ca and Mg in the hair of controls but not in that of CPPs. Antimony was found significantly negative in terms of its correlation with Co and Cu in CPPs group but not in the controls. Principal component analysis (PCA) of the data extracted seven factors for CPPs and six factors for controls. Cluster analysis (CA) was also used to support the PCA results. The study evidenced some specific source of Mg and Sb in the hair of CPPs.

Adolescent↗
PubMed1991

A multivariate analysis of cardiac growth in human embryos: endocardial cushions and ventricular myocardium.

STUDY OBJECTIVE: In view of the controversy about the morphological significance of the endocardial cushion tissue and ventricular myocardium during cardiac development, the aim was to carry out quantitative studies of these structures. DESIGN: Endocardial cushion tissue and ventricular myocardium were quantified by point count planimetry. The relative growth of the volume of these structures, and also the embryonic crown-rump length, was studied by multivariate allometry (principal components analysis) with the covariance matrix calculated from natural logarithms of the data. EXPERIMENTAL MATERIAL: 27 serially sectioned human embryos were studied, ranging from stage 15 to stage 23 (Paris collection). MEASUREMENTS AND MAIN RESULTS: The relative growth of endocardial cushion tissue, ventricular myocardium, and crown-rump length was discontinuous during the postsomitic period. The first component in principal components analysis measures overall size and, in the present analysis, accounts for 88.6% of the total variance. The growth vector isometry hypothesis was checked with the chi 2 test. This showed that differences in growth between cardiac structures and crown-rump length were allometric (p less than 0.01). Endocardial cushion tissue volume and crown-rump length grew with negative allometry during the second month of gestation, while ventricular myocardium volume grew with positive allometry. CONCLUSIONS: The results agree with those researchers who consider that endocardial cushion tissue functions only in causing initial cardiac fusion and partitioning, with little influence on the formation of definitive cardiac structures.

Heart↗
PubMed1988

Multiple drug combinations with "low-dose" cyclosporin for renal transplantation. Multivariate analysis of risk factors determining short-term graft survival within one renal transplant center.

The factors affecting graft survival in transplant recipients receiving cyclosporin (CsA) are still being debated. Our report is based on an analysis of 202 successive transplantations performed in our institution from May 1984 to December 1986, using low-dose CsA as the basic means of immunosuppression. A total of 142 patients received the triple combination CsA, azathioprine (AZA), and corticosteroids. Sixty patients received a prophylactic combination of CsA, corticosteroids, and antilymphocyte globulins (ALG). From January to December 1986, both regimens were compared in a prospective randomized trial. The factors that affect graft survival were analyzed using the Cox multivariate hazard analysis. The relative risks were calculated for pretransplant baseline risk factors and for outcome-dependent post-transplant risk factors for surviving grafts at 1 month. Transplants performed with a prolonged ischemia time and patients whose graft did not function immediately were statistically at higher risk of graft loss. Adding prophylactic ALG to CsA was associated with better graft survival. Patients who experienced more than 1 rejection crisis and patients whose 1-month CsA dose was lower than or equal to 5 mg/kg per day were also at significantly higher risk of further graft loss. Neither HLA matching, peak panel reactivity, age of the recipient, occurrence of post-transplant renal dysfunction nor 1-month renal function affected the short-term graft outcome.

Adrenal Cortex Hormones↗
PubMed1993

Prognostic factors in patients with metastatic malignant melanoma. A multivariate analysis.

BACKGROUND: Current methods to predict survival in patients with advanced, metastatic melanoma are limited. To determine clinical prognostic factors that accurately predict survival in patients with metastatic melanoma, a retrospective analysis was performed. METHODS: Clinical, hematologic, and biochemical pretreatment parameters from 284 patients entered on 18 Phase I and II clinical trials were analyzed to determine their prognostic effect on survival. A multivariate parametric regression based on the Weibull distribution was derived to estimate survival. RESULTS: Multivariate Weibull survival regression analysis showed that a simple model using the logarithm of the pretreatment values of lactate dehydrogenase and serum albumin, dichotomized as high and low, significantly and adequately predicted survival. A more complex multivariate model was also derived that involved the pretreatment platelet count, visceral organ involvement, and gender as additional factors. However, a larger study is needed to statistically validate such a model. CONCLUSIONS: The pretreatment values of serum lactate dehydrogenase and albumin are independent prognostic factors for survival in patients with metastatic melanoma. These two factors can be used to estimate survival of patients with advanced, metastatic melanoma and should be considered when designing melanoma trials in which survival is an endpoint.

Adult↗
PubMed1993

Risk factors for infection following operative treatment of mandibular fractures: a multivariate analysis.

Utilizing a retrospective study design and a study sample of 284 consecutive patients, we measured the association between five different risk factors and the development of infection following the operative management of mandibular fractures. The five risk factors analyzed were age, sex, number of fractures per patient, time from admission to treatment, and treatment modality. The overall infection rate was 5.3 percent. The infection rate for each treatment modality was (1) 0 percent for closed reduction, (2) 20.0 percent for open reduction and internal fixation with wire osteosynthesis, and (3) 6.3 percent for open reduction and rigid internal fixation. To measure the association between the various risk factors and postoperative infection, we used multivariate logistic regression. After controlling for potential confounding variables, the only risk factor statistically associated with postoperative infection was treatment modality.

Adult↗
PubMed2000

Perinatal asphyxia: multivariate analysis of risk factors.

UNLABELLED: Perinatal asphyxia contributes greatly to neonatal mortality and morbidity. In developing countries, the need for risk assessment in perinatal asphyxia is obvious because of the high birth rate and limited perinatal resources. OBJECTIVE: To determine the incidence and risk factors of perinatal asphyxia in infants who were delivered from mothers with high-risk conditions. STUDY DESIGN: A prospective study over a 5-year period from 1993 to 1997 was performed at a tertiary level, referral hospital. PATIENTS AND METHOD: Nine hundred and sixty-one infants who were delivered from 878 high-risk mothers were recruited. All of the risk factors that might have contributed to asphyxia were identified and recorded. Univariate and stepwise multiple logistic regression analysis was performed to identify significant factors that might have contributed to asphyxia, the odds ratios and 95 per cent confidence interval were computed. RESULTS: Abnormal fetal heart rate pattern, thick meconium stained amniotic fluid, and premature delivery, were three common risk factors for asphyxia. The mean gestational age was 37.6 +/- 3.5 weeks, 10.5 per cent (101/961) were infants less than 33 weeks. The incidence of asphyxia was 9.7 per cent and was highest (26.7%) in infants less than 1000 g. By univariate analysis, significant relationships between perinatal factors and asphyxia were found among birth weight, gestational age, premature and breech delivery but stepwise multiple logistic regression analysis revealed that only birth weight was significantly associated with perinatal asphyxia. CONCLUSION: In countries where resources are limited, a neonatal resuscitation team should be available for very low birth weight infants, premature and breech delivery.

Adult↗
PubMed2026

Bioaccumulation Patterns of Potentially Toxic Elements in Three Grouper Species from the Nizampatnam Coast, India: Multivariate Analysis and Risk Assessment.

The Indian Bay of Bengal coast represents an important marine fishing area and serves as a significant source of dietary protein for consumers. These highlights growing concerns regarding the bioaccumulation of potentially toxic elements (PTEs) in fish and the associated environmental and human health risks linked to their consumption. Thus, this study aims to assess the accumulation of PTEs (As (arsenic), Sr (strontium), Ti (titanium), Be (beryllium), Cd (cadmium), Sb (antimony), Pb (lead), Hg (mercury), and Li (lithium)) in the muscles of three groupers. The highest value (29.88&#x2009;&#xb1;&#x2009;0.17&#xa0;&#xb5;g/g dry wt.) was observed in Epinephelus areolatus for As, and the lowest in E. bleekeri for Be (0.59&#x2009;&#xb1;&#x2009;0.20&#xa0;&#xb5;g/kg dry wt.). Multivariate analyses (PCA and HCA) confirmed a very close relationship among the As, Cd, Sb, Ti, and Be, while Pb, Hg, Th, and Li had their own specific habitats of bioaccumulation, implying distinct inputs of PTE. Health risk evaluations reveal that As was the most hazardous PTE, with the incidence of toxic effects and cancer risk, especially for habitual consumers. However, Ti is the most hazardous PTE, posing the highest non-carcinogenic risk of the studied species. Metal-protein docking further showed the strong binding of Pb2+ and Sr2+ to Nrf2, p53, and DNMT1, indicating potential disruption of redox regulation, genomic stability, and epigenetic control. The findings indicate that the intake of the specified grouper species poses a significant arsenic-related health risk to people, underscoring the necessity for ongoing monitoring and management of PTE contaminants in fisheries.

Animals↗
PubMed1995

Quantitative multivariate analysis of myoepithelioma and myoepithelial carcinoma.

The nuclear DNA content and morphologic data of 30 surgical samples (eight normal parotid gland, 12 myoepithelioma, and 10 myoepithelial carcinoma) were analyzed by the IBAS II analysis system. The results suggest that there are relationships between tumor ploidy distribution and prognosis, and that correct pathologic diagnosis can be obtained by the IBAS image system.

Adolescent↗
PubMed2006

Oocyte degeneration after intracytoplasmic sperm injection: a multivariate analysis to assess its importance as a laboratory or clinical marker.

OBJECTIVE: Oocyte degeneration has historically been associated with the intracytoplasmic (ICSI) technique. We sought to determine whether oocyte degeneration rates were associated with the technician performing the procedure, the baseline characteristics of the patient, and/or ovarian stimulation variables. We also evaluated whether the degeneration rate could serve as a surrogate marker for implantation potential. DESIGN: Cohort study. SETTING: Academic medical center. PATIENT(S): Couples undergoing ICSI. INTERVENTION(S): Six thousand six hundred fifty-three injected oocytes were analyzed to determine whether the degeneration rate was technician dependent. Two hundred thirty first-entry down-regulated cycles were examined to identify predictors associated with oocyte degeneration. Multivariate analyses were performed using generalized linear model routines. MAIN OUTCOME MEASURE(S): Oocyte degeneration rates and implantation rates. RESULT(S): Neither the ICSI technician nor the stripping technician was associated with the oocyte degeneration rate. However, the day 3 FSH, number of mature oocytes retrieved, and E2 levels on the day of hCG were significant independent predictors of degeneration rate. Physician-adjustable ovarian stimulation variables were not associated with the degeneration rate. The degeneration rate did not appear to be associated with the implantation rate. CONCLUSION(S): These data suggest that oocyte degeneration is not technician or physician dependent. Degeneration is likely a function of the inherent oocyte quality in women who underwent ovarian stimulation. However, the remaining cohort of retrieved oocytes appears to be unaffected by virtue of an uncompromised implantation rate.

Adult↗
PubMed2000

Multivariate analysis of diet among three-year-old children and associations with socio-demographic characteristics. The Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) Study Team.

STUDY OBJECTIVE: The study of the whole diet in combination rather than the consumption of individual food items or the intake of specific nutrients could be enlightening. This has been previously performed using principal components analysis (PCA) on adult diets but not on those of children. DESIGN: The frequency of consumption of a range of food items was recorded for 10,139 3-y-old children by their mothers using self-completion postal questionnaires. These children form part of the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC). METHODS: PCA was performed to identify individual dietary types which were then related to various socio-economic and demographic characteristics. RESULTS: Four distinct dietary components were obtained explaining 23.5% of the total variation in the sample, and the socio-demographic characteristics of the sample were related to them. The first represented a diet based on convenience foods and was associated with younger, less educated mothers and the presence of older siblings. The second was associated with a high consumption of foods currently considered to be healthy and was particularly related to vegetarian mothers and higher education levels. The third component described the established British 'meat and two veg' diet and was associated with girls and children with no older siblings, while the fourth had high loadings for snack and finger foods and was related to socially advantaged conditions and the presence of older siblings. CONCLUSIONS: Identifiable groups of mothers were associated with feeding their child each of the four dietary types, supporting the hypothesis that social, demographic and lifestyle factors relating to the mother have an influence on the early eating patterns of children. This analysis will form a basis for the future study of various childhood outcomes including growth, health and development. SPONSORSHIP: University of Bristol European Journal of Clinical Nutrition (2000) 54, 73-80

Adult↗
PubMed1989

[Study on the behavior management at dental treatment. Research of various factors affecting the frequency of training by multivariate analysis].

A Search was made using quantification methods of the first and second type to discover the factors affecting the frequency of training, and to estimate it. The following conclusions were obtained; 1. Factors having a large effect on the decision of the frequency of training were the Frankl classification, ages at the initial examination and if children have any experience of dental treatment or not. 2. With the factors concerned with educational environments encompasing mothers, number of brothers and sisters, the mother's educational history and wether the mothers work or not high correlation was shown. 3. Among the factors concerned with character analysis, emotional stability, if children can control themselves or not had considerable effect. 4. As for the factors for estimating the frequency of training, the reliable factors include Frankl classification, ages at initial examination, and sexes. 5. With the factors concerned with educational environment including mothers, the mothers' educational history, the number of brothers and sisters, birth order were highly reliable. 6. With the factors concerned with character analysis, emotional stability, if children are degenerative or productive showed high reliability. 7. Multiple correlation coefficient for all the 27 factors was 0.823, which was found to be highly reliable for the estimation of the frequency of training.

Behavior Therapy↗
PubMedDate not supplied

Radical radiotherapy for T4 carcinoma of the skin of the head and neck: a multivariate analysis.

Sixty-seven patients with 68 stage T4 carcinomas of the skin of the head and neck were treated with radical radiotherapy at the University of Florida between October 1964 and November 1989. Thirty-three lesions were previously untreated and 35 were recurrent. Twenty-nine lesions were squamous cell carcinomas, 37 were basal cell carcinomas, and 2 were basosquamous carcinomas. Minimum follow-up was 2 years. The 5-year local control, local control including surgical salvage, and cause-specific survival probabilities were 53%, 74%, and 75%, respectively. Local control rates with radiotherapy alone were poorer in patients with recurrent lesions (41% vs. 67%, p = .07) or bone involvement (40% vs. 62%, p = .08). Results were analyzed by multivariate methods using local control, local control with surgical salvage, and cause-specific survival as endpoints. The parameters analyzed were histology; size of primary lesion; previous treatment (previously untreated vs. recurrent); involvement of bone, nerve, or cartilage; and skeletal muscle invasion. Three important prognostic factors were identified, each predictive of poorer ultimate local control and cause-specific survival rates: (a) bone involvement (p < .01); (b) recurrent lesions (p < .01); and (c) nerve involvement (p < .02). Radiotherapy alone can control advanced carcinomas of the skin of the head and neck, although lesions that have recurred after prior treatment and those with involvement of bone or nerve are associated with a lower likelihood of cure.

Brachytherapy↗