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PubMed1995

[Prognostic factors of hepatocellular carcinoma: a multivariate analysis in 113 patients].

UNLABELLED: The aim of this study was to identify clinical, biological or morphological prognostic factors in 113 patients with HCC in terms of survival. All patients (100 men, aged 65 [28-85], 95% cirrhosis) were diagnosed between 1982-1990. Mean survival time was 21 +/- 3 weeks. Eleven (over 25) variables were isolated by univariate analysis. A multivariate survival analysis (Cox regression model) disclosed that serum creatinine (p = 0.0002), alkaline phosphatase (p = 0.02) and Okuda's stage (p = 0.025) were independent predictors of survival. Comparison of survival curves for different values of these prognostic variables allows division of patients in three groups of prognostic significance in terms of survival (p < 0.05). CONCLUSION: these results facilitate stratification of patients with HCC to design and evaluate future controlled trials.

Aged↗
PubMed2000

Factors associated with the development of recurrent acute otitis media--the significance of choosing the right and accurate dependent and independent variables in the multivariate analysis.

The results of univariate and multivariate statistical analysis were compared in identifying predictive factors of the development of recurrent acuta otitis media (RAOM) after an initial episode of acute otitis media (AOM) in 121 children. Univariate correlations between the development of RAOM and potential risk factors were analysed, and variables at p < 0.10 were incorporated into the stepwise multiple logistic regression analysis. The comparisons between the univariate and multivariate analysis in identifying the predictive factors were made and the importance of changing the dependent variables in the multivariate analysis was analysed. It seems that univariate analysis is over-sensitive, but multivariate analysis is over-conservative in finding possible predictors of RAOM. Choosing the right and accurate dependent and independent variables in the multivariate analysis is extremely important, when this method is used.

Acute Disease↗
PubMed1999

[Multivariate analysis of clinical factors in restenosis after coronary interventional treatment].

OBJECTIVE: To found the independent predictors for restenosis after coronary interventional treatment. METHODS: Quantitative angiography was performed in 103 patients(128 successfully dilated lesions) at angioplasty and at 6-month follow-up, and then univariate analysis and multivariate logistic regression analysis were performed to identify correlates of restenosis with clinical factors. RESULTS: The total restenosis rate was 39.8% (51 of 128 lesions). According to univariate analysis, the patients who had undergone coronary tenting > or = 3.5 mm had a lower rate of restenosis(3/29 and 6/30) and the others with the ACC/AHA lesion type B and C(46/51 and 51/77), collateral circulation to the obstruction set(17/51 and 2/77), high percentage diameter stenosis before PTCA(86 +/- 14)% and (79 +/- 15)%, and high maximal inflation pressure(8.3 +/- 2.1) kPa and (7.4 +/- 1.7) kPa had a higher rate of restenosis (P < 0.01). Stable angina showed a low restenosis rate (3/29 and 6/30). The less minimal lumen diameter before(0.43 +/- 0.41) mm and (0.66 +/- 0.43) mm and after PTCA(2.56 +/- 0.55) mm and (2.85 +/- 0.59) mm, had the higher the restenosis rate (P < 0.05). Multivariate logistic regression analysis showed that coronary stenting had a low rate of restenosis, and that lesion type B and C, high percentage diameter stenosis before PTCA, high maximal inflation pressure, and male had a high rate of restenosis. CONCLUSION: Coronary stent, percentage diameter stenosis before PTCA, lesion type, maximal inflation pressure, and sex were independent predictors for restenosis.

Aged↗
PubMed2005

Comparative study of survival of patients with hepatocellular carcinoma predicted by different staging systems using multivariate analysis.

AIMS: In a previous pilot study, we reported the usefulness of the modified the Cancer of the Liver Italian Program (CLIP) score for patients with hepatocellular carcinoma (HCC). To determine the best staging system for predicting the survival of HCC patients, we conducted a comparative analysis of prognosis using multivariate analysis in 210 Japanese HCC patients who underwent hepatic resection. METHODS: We compared the survival as predicted by various staging systems, including tumour node metastasis (TNM) stage of the American Joint Commission on Cancer (AJCC) and the Liver Cancer Study Group of Japan, the Japan Integrated Staging (JIS) score (Japanese TNM and Child-Pugh classification), CLIP score and our modified CLIP score using protein induced by vitamin K absence or antagonist II (PIVKA-II). RESULTS: Univariate analysis showed that discrimination of disease-free survival in the early and advanced stages by the JIS score and modified CLIP score was clearer than by the Japanese or AJCC TNM or the original CLIP score. Discrimination between stages of overall survival by all staging systems was significant. Multivariate analysis showed that the JIS, CLIP and modified CLIP scores were better staging systems for predicting survival than the Japanese and AJCC TNM. The modified CLIP score showed the lowest Akaike information criteria statistical value for disease-free and overall survival, which means the best discrimination ability for patient survival compared with the JIS score and CLIP score. CONCLUSIONS: A staging system that combines tumour factors, sensitive tumour marker(s) and hepatic function is the best predictor of prognosis of HCC patients.

Adult↗
PubMed1997

Risks of the minimal access approach for laparoscopic surgery: multivariate analysis of morbidity related to umbilical trocar insertion.

The objective of this study was to determine the morbidity associated with trocar and needle insertion for laparoscopic surgery and to identify risk factors for complications. Data from a prospectively collected database of all laparoscopic operations performed at a major teaching hospital over a 4-year period were analyzed. In 203 patients closed laparoscopy (Veress needle plus blind trocar insertion) was used to establish the pneumoperitoneum. Open laparoscopy with a Hasson's trocar was performed in 200 patients. A total of 1206 operative trocars were inserted (mean +/- SD 2.99 +/- 0.4). Sixty-nine percutaneous punctures for cholangiography or liver biopsy were carried out. Of the 403 patients undergoing laparoscopic surgery, 20 (3%) had developed complications specifically related to the access to the abdominal cavity after a minimum follow-up of 3 months, abdominal wall hematoma being the most frequent (n = 8, 2.0%), followed by umbilical hernias (n = 6, 1.5%) and umbilical wound infection (n = 5; 1.2%). The rate of penetrating injuries was 0.2% (n = 1). Of 20 complications, 15 (75%) were related to the umbilical insertion site. Female sex and closed laparoscopy were associated with umbilical morbidity by univariate analysis. In a multivariate analysis, closed laparoscopy was the only factor associated with these complications (odds ratio = 6.0; p = 0.04). Age, gender, obesity, diabetes mellitus, previous abdominal surgery, and the specific procedure had no influence. In conclusion, gaining access to the peritoneal cavity for laparoscopic surgery may cause severe complications, most of which are related to the umbilical trocar. Although closed laparoscopy can be safely used, open laparoscopy is associated with a lower morbidity rate; therefore its utilization is recommended.

Abdominal Muscles↗
PubMed2002

Determination of wheat quality by mass spectrometry and multivariate data analysis.

Multivariate analysis has been applied as support to proteome analysis in order to implement an easier and faster way of data handling based on separation by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The characterisation phase in proteome analysis by means of simple visual inspection is a demanding process and also insecure because subjectivity is the controlling element. Multivariate analysis offers, to a considerable extent, objectivity and must therefore be regarded as a neutral way to evaluate results obtained by proteome analysis. Proteome analysis of storage proteins from the wheat gluten complex based on two-dimensional electrophoresis and analysis of the N-terminal sequence has revealed a protein homologous to gamma-gliadins, tentatively associated with quality and within the molecular weight range 27-35 kDa. Further examinations of gliadin data based on mass spectrometry revealed that quality among wheat varieties could be determined by means of principal component analysis. Further examinations by interval partial least squares made it possible to encircle an overall optimal molecular weight interval from 31.5 to 33.7 kDa. The use of multivariate analysis on data from mass spectrometry has thus shown to be a promising technique to minimize the number of two-dimensional gels within the field of proteome analysis.

Gliadin↗
PubMed2006

Prediction of shoulder dystocia using multivariate analysis.

We evaluated the use of multivariate analysis in the prediction of shoulder dystocia (SD). One hundred consecutive cases with SD were matched with 100 controls without dystocia. All patients had term, vaginal delivery. Multivariate analysis was used to identify independent variables significantly related to shoulder dystocia. The regression coefficients for the identified factors were used to calculate a composite score from which receiver operating characteristics (ROC) curves were derived. Birthweight (BW), 1-hour Glucola (GLU), operative vaginal delivery (OVD), and height of fundus (HOF) were related independently to SD. The sensitivity and specificity reached 84 and 80%, respectively, with BW + GLU + OVD. Significant associations persisted when HOF and carbohydrate intolerance were substituted for BW and GLU, respectively. SD is independently associated with BW, GLU, and OVD, and may be predicted with clinically acceptable accuracy using multiple variables. This model may be useful in the design of prospective studies for managing suspected macrosomia.

Adult↗
PubMed1995

Clinical risk factors for pulmonary barotrauma: a multivariate analysis.

Previous investigations have suggested that elevated airway pressures increase the risk of ventilator-induced pneumothorax. However, risk factor analysis using multivariate techniques has not been done. We investigated the hypothesis that airway pressures would not independently correlate with pneumothorax when underlying disease was considered. All ventilated patients over a 1 yr period in the Hohenburg Critical Care Unit at the University of Alabama were followed until death or discharge from the ICU. Ventilator data were collected daily and the presence of pneumomediastinum and pneumothorax determined by review of chest radiographs. Maximal values of airway pressures, minute ventilation, tidal volume, and respiratory rate, as well as age, sex, and underlying disease, were entered into logistic regression analysis. A total of 168 patients was studied, and 20 experienced pneumothorax. Multivariate analysis of the entire ventilated population revealed that only the presence of ARDS independently correlated with pneumothorax. A similar analysis performed on the ARDS population revealed independent correlation only with male sex. Trends toward elevation in airway pressures were seen that did not reach statistical significance. We conclude that development of pneumothorax is most closely correlated with underlying disease, specifically ARDS, and that the associations previously noted between airway pressures and barotrauma largely relate to the occurrence of high airway pressures in ARDS.

Adult↗
PubMed2005

Multivariate analysis of the neurological outcome of surgery for cervical compressive myelopathy.

BACKGROUND: The neurological outcome of decompressive surgery for cervical myelopathy is influenced by several factors. Although each factor may have an independent effect, it is more likely that the outcome is influenced by more than one factor. We examined the results of multivariate analysis and multiple regression analysis of the neurological outcome of patients treated by cervical cord decompression. METHODS: A total of 77 patients with cervical spondylotic myelopathy (43 men, 34 women) and 58 with ossification of the posterior longitudinal ligament (OPLL) (39 men, 19 women) were studied with an average follow-up interval of 8.3 years. The clinical data, neurological and radiological findings, and results of spinal cord evoked potentials (SCEPs) were retrieved from the medical records and included in the analysis. RESULTS: Multivariate analysis indicated that the outcome for patients with spondylosis was positively influenced, in order of importance, by increased transverse area of the cord >or=60%, presence of single-level anterior fusion, a high preoperative neurological score, normal epidural SCEPs, and clinical features of brachialgia and cord type. In patients with OPLL, multivariate analysis showed that the long-term outcome was positively influenced, in order of importance, by the presence of mixed or localized OPLL, normal epidural SCEPs, high preoperative neurological score, a single-vertebra spondylectomy with anterior fusion, laminoplasty, widening of the transverse area of the cord >or=40%, and an expansion rate of the spinal canal after laminoplasty >or=40%. CONCLUSIONS: We suggest that multivariate analysis is useful for assessing the neurosurgical outcome in patients with cervical compressive myelopathy.

Adult↗
PubMed1997

Prognostic factors for renal cell carcinoma: a multivariate analysis of 320 cases.

BACKGROUND: We performed a multivariate analysis of clinical variables in 320 patients with renal cell carcinoma to identify important prognostic factors for long-term survival. METHODS: We retrospectively reviewed the medical records of 320 patients who presented with renal cell carcinoma. Survival curves were calculated by the Kaplan-Meier method and statistical differences were determined by the log-rank test. Significant prognostic factors were evaluated by Cox's multivariate proportional hazard model. RESULTS: The median follow-up period was 29 months. The overall survival rates at 1, 5, and 10 years were 90.0%, 77.6%, and 69.9%, respectively. Seventeen of the 19 prognostic factors evaluated were shown to be significant by the log-rank test: patient age, sex, performance status, body temperature, erythrocyte sedimentation rate (ESR), levels of hemoglobin, alpha 2-globulin, C-reactive protein, fibrinogen, immunosuppressive acidic protein (IAP), size or involvement of tumor (T classification), regional lymph node involvement (N classification), extent of metastasis (M classification), pathologic grade, tumor cell type, mode of tumor infiltration, and the modality of treatment (curative surgery). Among them, the body temperature, ESR, alpha 2-globulin, fibrinogen, IAP, and mode of tumor infiltration were excluded from multivariate analysis because of missing data. Curative surgery was also excluded because it is a treatment modality and different from the other variables which are clinical or pathologic characteristics. From the remaining 10 variables, multivariate analysis showed that age (P = 0.0389), N classification (P = 0.0289), and M classification (P < 0.0001) were important and independent prognostic factors for long survival. CONCLUSION: This analysis showed that age, N classification, and M classification were the most important factors predicting long-term survival of patients with renal cell carcinoma.

Adult↗
PubMed1998

Multivariate analysis of prognostic factors in resected colorectal cancer: a new prognostic index.

OBJECTIVE: We analysed different clinicopathological variables in colorectal cancer and their independent prognostic significance in order to elaborate a prognostic index, which may be used to categorize patients into homogeneous groups and indicate adjuvant therapy. DESIGN: Retrospective study. METHODS: Patients (n = 108) undergoing surgery for colorectal cancer were studied (5-year-survival was controlled). Different clinicopathological variables and biological parameters (tumoural ploidy, proliferating cell nuclear antigen PCNA and nucleolar organizing regions NORs) were analysed. The Kaplan-Meier method and log-rank test were used for univariate analysis and the Cox regression method was used for multivariate analysis. RESULTS: Some variables with prognostic effect in univariate analysis (e.g. rectal bleeding, altered bowel habit, intestinal obstruction, type of surgery, histological type, venous and neural invasion and invasive margin) did not have independent prognostic significance after Cox analysis. Final multivariate analysis model was defined by five parameters: postoperative carcinoembryonic antigen, Astler-Coller-Turnbull staging, histological grade, lymphatic invasion and tumour ploidy. A new prognostic index was elaborated that provided information to group patients in three prognostic categories of different risk: high, medium and low. CONCLUSION: The prognostic index allowed categorization of patients into different risk groups with identical tumoural stage and histological grade. Therefore, this index provides better prognostic information that may be helpful when selecting patients for adjuvant therapy.

Adenocarcinoma↗
PubMed1988

Diabetic neuropathy as a heterogeneous syndrome: multivariate analysis of clinical and neurological findings.

We quantitatively assessed peripheral and autonomic nerve function in diabetic patients and compared them with various parameters of their diabetic status. Motor and sensory nerve conduction velocity (MCV, SCV), vibratory perception threshold (VPT) and the coefficient of variation of the ECG R-R interval (CV R-R) were measured in 85 diabetic patients aged 20-59 years. These values were compared with those of age-matched healthy subjects. Moreover, in 53 patients, MCV, SCV, VPT and CV R-R were investigated by multivariate analysis in relation to clinical parameters. In diabetics, MCV, SCV and CV R-R were significantly lower and VPT was higher than in age-matched healthy controls. The prevalence of impaired values in diabetics was 70% for VPT in the toe, 60% for SCV, and 55% for MCV, CV R-R and VPT in the finger. Impairments of MCV, SCV, CV R-R and VPT were closely correlated with diabetic retinopathy, proteinuria and duration of disease. Categorical regression analysis (multivariate analysis) revealed that the impairment of conduction velocity was closely related to diabetic retinopathy and to hypo- or areflexia, that the impairment of the vibratory perception threshold was related to ischemic changes in ECG and to hypo- or areflexia, and that the reduction of CV R-R was related to orthostatic hypotension and to proteinuria. These findings suggest that diabetic neuropathy progresses in parallel with other complications, and that it is a heterogeneous syndrome rather than a single entity.

Adult↗
PubMed2005

Development of a perfusion reversed-phase high performance liquid chromatography method for the characterisation of maize products using multivariate analysis.

A perfusion reversed-phase high performance liquid chromatography (RP-HPLC) method has been designed to allow rapid (3.4 min) separations of maize proteins with high resolution. Several factors, such as extraction conditions, temperature, detection wavelength and type and concentration of ion-pairing agent were optimised. A fine optimisation of the gradient elution was also performed by applying experimental design. Commercial maize products for human consumption (flours, precocked flours, fried snacks and extruded snacks) were characterised for the first time by perfusion RP-HPLC and their chromatographic profiles allowed a differentiation among products relating the different technological process used for their preparation. Furthermore, applying discriminant analysis makes it possible to group the samples according with the technological process suffered by maize products, obtaining a good prediction in 92% of the samples.

Chromatography, High Pressure Liquid↗
PubMed2006

Prediction of oil and oleic acid concentrations in individual corn (Zea mays L.) kernels using near-infrared reflectance hyperspectral imaging and multivariate analysis.

Due to their heterogeneous structure and variability in form, individual corn (Zea mays L.) kernels present an optical challenge for nondestructive spectroscopic determination of their chemical composition. Increasing demand in agricultural science for knowledge of specific traits in kernels is driving the need to find high-throughput methods of examination. In this study macroscopic near-infrared (NIR) reflectance hyperspectral imaging was used to measure small sets of kernels in the spectroscopic range of 950 nm to 1700 nm. Image analysis and principal component analysis (PCA) were used to determine kernel germ from endosperm regions as well as to define individual kernels as objects out of sets of kernels. Partial least squares (PLS) analysis was used to predict oil or oleic acid concentrations derived from germ or full kernel spectra. The relative precision of the minimum cross-validated root mean square error (RMSECV) and root mean square error of prediction (RMSEP) for oil and oleic acid concentration were compared for two sets of two hundred kernels. An optimal statistical prediction method was determined using a limited set of wavelengths selected by a genetic algorithm. Given these parameters, oil content was predicted with an RMSEP of 0.7% and oleic acid content with an RMSEP of 14% for a given corn kernel.

Agriculture↗
PubMed1980

[Neutron activation analysis of human hair--multivariate analysis of factors influencing on trace element contents in hair-- (author's transl)].

As a part of IAEA research project, "Activation analysis of hair as an indicator of contamination of man by environmental trace element pollutants", a survey was carried out to elucidate the levels of various trace element concentrations in hair of local population in the Tokyo Metropolitan areas, by applying instrumental neutron activation analysis. A total of 202 scalp hair samples were collected from the inhabitants classified by sex and five age classes. Irradiation was made in the Rikkyo University 100 kW TRIGA MARK-II reactor. Using several combinations of irradiation time, cooling time and counting time, forty elements were determined. The relationship between several trace element contents in hair and such factors as sex, age class, hair treatment, smoking habit and dental treatment, was analyzed by using the method of multiple regression. It was shown that (1) Hair treatment had a predominant effect on the contents of bromine, magnesium and calcium in hair, (2) Aging and smoking contributed increasing mercury content in hair, and hair treatment acted reversely.

Adolescent↗
PubMed2005

Intramedullary nailing for open fractures of the femoral shaft: evaluation of contributing factors on deep infection and nonunion using multivariate analysis.

The purpose of this study was to use multivariate analysis to evaluate contributing factors affecting deep infection and nonunion of open femoral fractures treated with locked intramedullary nailing (IMN). We examined 89 open femoral fractures (88 patients) treated with immediate or delayed locked IMN in static fashion at the Kitasato University Hospital from 1988 to 2001. Multiple regression models were derived to determine predictors of deep infection and nonunion. The following predictive variables of deep infection were selected for analysis: age, sex, Gustilo type (I+II or III), fracture grade by AO type (A or B+C), fracture site (proximal site+distal site or middle site), timing or method of IMN, reamed or unreamed nailing (R versus UR), debridement time (< or =6 h or >6 h), existence of polytrauma (ISS<18 or ISS> or =18), and existence of floating knee injury (+ or -). The predictive variables of nonunion selected for analysis were the same as those for deep infection, with the addition of deep infection (+ or -). Five fractures (5.6%) developed deep infections: one Gustilo type II and four type III. Multivariate analysis revealed that only Gustilo type significantly correlated with occurrence of deep infection (p<0.05). Nonunion occurred in 12 fractures (14.1%). Multivariate analysis revealed that only fracture grade by AO type significantly correlated with occurrence of nonunion (p<0.02).

Adolescent↗