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PubMed1988

Prognostic factors in chronic myelodysplastic syndromes: a multivariate analysis in 107 cases.

A retrospective multivariate analysis of 37 clinical, biochemical, and hematological data was performed in 107 cases of primary myelodysplastic syndromes (MDS) in order to recognize their prognostic significance. The most important individual variables, isolated in a previous univariate analysis, were placed in a multiple regression modeling procedure to identify major significant prognostic factors. Multivariate analysis tends to identify prognostic variables containing significant independent predictive information. Characteristics were examined on both continuous and binary bases. The FAB classification was the first parameter entered in regression equations on both models, followed by platelet count, hemoglobin level, and circulating erythroblasts in the binary model, and by hemoglobin level, systemic symptoms, platelet count, age, and dyserythropoiesis in the continuous model. Our analysis confirms FAB classification as the main prognostic factor in MDS, supports the previously noted predictive value of platelet count, hemoglobin level, and age, and recognises the importance of circulating erythroblasts, systemic symptoms, and dyserythropoiesis as prognostic characteristics in MDS.

Adult↗
PubMed1977

Structural analysis of the ridge count data of Australian Europeans using multivariate analysis.

Multivariate analyses are used to study the structural patterns of ridge counts of fingers. There is a significant difference between the ridge counts of two hands, chiefly due to the first and fourth fingers. There is asymmetry in the covariance matrix of the ridge counts. The correlations between fingers are significant and the decrease in correlation with increasing distance between fingers is not significant.

Australia↗
PubMed1991

[Multivariate analysis of prognostic factors in patients with prostatic cancer].

A multivariate statistical analysis of 9 potential prognostic factors was made, using data gathered on 107 patients admitted between 1975 and 1987. After each variable was assessed separately for its prognostic importance by means of univariate analysis, a multivariate analysis using Cox's proportional hazards regression model and multivariate logistic model was done. These tests identified Gleason's score as the most important factor for all patients followed by M category and alkaline phosphatase (ALP), while Gleason's score alkaline phosphatase and age at diagnosis were most important for stage D patients. For short-term survival, the significant prognostic factors were Gleason's score and M category while for long term survival they were Gleason's score and age. T. category, stage, acid phosphatase, prostatic acid phosphatase, and treatment were found to be significantly related to survival time when examined individually; they were not found to be significant in the multivariate analysis.

Age Factors↗
PubMed2000

[Risk factors for preeclampsia. Multivariate analysis].

OBJECTIVE: To determine in multivariate analysis the clinical, social, and demographic factors for preeclampsia. STUDY DESIGN: A case-control study was designed. Three hundred patients were included, divided in two groups. 150 cases with criteria diagnosis for preeclampsia. 150 patients with normal pregnancy and deliveries. The main variables analyzed were age, schooling, marital status, employment, socioeconomic status, smoking and alcohol consumption, body mass index, familiar history of preeclampsia, history of preeclampsia in previous pregnancy, parity and type of pregnancy (single or multiple). STATISTICAL ANALYSIS: For comparison of cases and controls on categorical variables, odds ratios and 95% confidence intervals were calculated, and multiple logistic regression analyses. RESULTS: Multiple logistic regression analysis showed that history of preeclampsia in previous pregnancy has OR 23.7, 95% p < 0.001, familiar history of preeclampsia OR 1.62, p < 0.08, high body mass has OR 1.60. CONCLUSIONS: The knowledge of the most important risk factors in our population could be useful for the clinical to pre-detect the patient who will develop preeclampsia.

Adult↗
PubMed1991

Prognosis of unresectable hepatocellular carcinoma: an evaluation based on multivariate analysis of 90 cases.

A multivariate analysis of data from 90 patients with unresectable hepatocellular carcinoma was performed using Cox's regression model to identify factors possibly affecting their prognoses. Thirty-one patients underwent arterial anticancer chemotherapy, and the remaining 59 patients received transcatheter arterial embolization with anticancer agents. Four of 27 variables tested for all the patients (i.e., encapsulation [p less than 0.05], gross appearance of hepatocellular carcinoma [p less than 0.01], clinical stage [p less than 0.01] and therapy [p less than 0.01]) were found to be prognostically significant. Five of 27 variables tested were prognostically significant for the transcatheter arterial embolization group; they were an extension rate of hepatocellular carcinoma (p less than 0.01), encapsulation (p less than 0.01), alpha-fetoprotein (p less than 0.01), prothrombin time (p less than 0.01) and serum sodium (p less than 0.01). Regression equations were used to describe a prognostic index. A prognostic index was defined as the regression equation derived from the results of a total of 90 patients; PI-1 = eY, where PI-1 = prognostic index 1 Y = 1.549 (gross appearance of hepatocellular carcinoma - 1.344) + 0.778 (encapsulation - 1.622) + 0.818 (clinical stage - 1.800) + 1.760 (therapy - 1.344) and prognostic index 2, the regression equation derived from the results of the transcatheter arterial embolization group of patients; PI-2 = eY, where PI-2 = prognostic index 2 Y = 1.210 (extension rate of hepatocellular carcinoma - 1.576) + 1.179 (encapsulation - 1.475) + 0.0001277 (alpha-fetoprotein - 1420.792) -0.039 (prothrombin time - 72.237) - 0.214 (serum sodium - 138.427).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Enhanced efficacy of computerized exercise test by multivariate analysis for the diagnosis of coronary artery disease. A study of 558 men without previous myocardial infarction.

Multivariate analysis has been proposed to enhance diagnostic accuracy of the exercise test in coronary artery disease. To quantify the improvement given by multivariate analysis in comparison with ST segment depression alone during exercise test, 558 men without previous myocardial infarction were studied retrospectively. All the patients underwent a symptom-limited Bruce protocol with computer-averaged recordings in V5, aVF, V2. Coronary angiography was performed within the following 90 days. Prevalence of coronary artery disease (diameter narrowing of 50% or greater) was 0.56. Among 12 clinical and exercise parameters studied by stepwise multivariate analysis, five were found to reach the maximal accuracy: (1) exercise duration, (2) history of typical angina, (3) typical angina during the test, (4) age, (5) maximal heart rate. In comparison with ST depression, multivariate analysis significantly improves accuracy (74.6 vs. 66.8%, P less than 0.01) by increasing sensitivity (0.68 vs. 0.59, P less than 0.05) without affecting specificity (0.83 vs. 0.76, NS). Thus, in a group of men without infarction and a low prevalence of coronary artery disease, multivariate analysis with five easily collected variables is more accurate than ST segment depression alone during exercise. In addition, ST depression did not appear as discriminant as exercise duration for diagnostic purposes. This finding emphasises the importance of performing a symptom-limited exercise test.

Adult↗
PubMed1994

A multivariable analysis of clinical factors predicting for pathological features associated with local failure after radical prostatectomy for prostate cancer.

PURPOSE: A multivariate analysis is used to determine the predictive value of pretreatment clinical indicators on pathologic features associated with local failure after radical prostatectomy in patients with prostate cancer. METHODS AND MATERIALS: A retrospective review of the pathologic findings of 235 patients with adenocarcinoma of the prostate treated between 1990 and 1993 with a radical retropubic prostatectomy was performed. The preoperative clinical data including the serum prostate specific antigen, clinical stage, Gleason sum, and endorectal magnetic resonance scan findings are used to identify patients prior to definitive treatment who would be at high risk for having pathologic features associated with local failure at radical prostatectomy. Outcome prediction curves are constructed from a logistic regression multivariate analysis displaying the probability of pathologic involvement of the seminal vesicle, extracapsular disease, or positive surgical margins as a function of the preoperative prostate specific antigen and Gleason sum for the cases when the endorectal magnetic resonance scan is positive, negative, or not included in the multivariate analysis. RESULTS: Factors identified on multivariate analysis as significant predictors of seminal vesicle invasion include endorectal magnetic resonance scan findings (p < 0.0001), and preoperative prostate specific antigen (p = 0.017). Endorectal magnetic resonance scan findings (p = 0.0016), preoperative prostate specific antigen (p = 0.0002), and Gleason sum (p < 0.0001) were significant predictors of extracapsular extension and preoperative prostate specific antigen (p < 0.0001) and Gleason sum (p = 0.03) were significant predictors of disease extending to the margins of resection. Clinical stage was not a significant predictor (p > 0.05) of pathologic features associated with local failure on multivariate analysis. As a single modality, endorectal surface coil magnetic resonance imaging was accurate 93%, 69%, and 72% of the time for predicting seminal vesicle invasion, transcapsular disease, and final pathologic stage, respectively. Failure to recognize microscopic penetration of the capsule found at the time of pathologic evaluation in a prostate gland with a grossly intact capsule accounts for the majority (70%) of the staging inaccuracies. CONCLUSIONS: The use of the endorectal surface coil magnetic resonance scan findings in conjunction with both the serum prostate specific antigen and Gleason sum improves the clinical accuracy of predicting those patients at high risk for clinically unsuspected extraprostatic disease. In particular, for the subgroup of patients with moderately elevated prostate specific antigen (> 10-20 ng/mL) and intermediate grade clinically organ confined prostate cancer [Gleason sum: 5-7] where the specificity of these tests to predict for occult extraprostatic disease is suboptimal, the additional information obtained from the endorectal coil magnetic resonance scan allows the physician to definitively subgroup these patients into low and high risk for seminal vesicle invasion or transcapsular disease.

Adenocarcinoma↗
PubMed1996

Predictors of outcome of epilepsy surgery: multivariate analysis with validation.

PURPOSE: To identify predictors of outcome of epilepsy surgery, using the Duke experience, applying multivariate analysis and validation techniques. To compare the results of different modeling algorithms. Few previous studies have reported multivariate analysis, or validated their results. METHODS: Records of 116 patients with focal resections for intractable epilepsy from January 1, 1980 through June 30, 1989 were analyzed. Primary outcome variable was patient's condition in second postoperative year: seizure free (except auras), or not. Three predictors of biologic interest were specified a priori for confirmatory analysis. Additional predictors were considered within exploratory analysis. Logistic regression techniques were applied to assess relations with pre- and postoperative predictors. Internal validity was assessed by repeated random selection of training and validation samples, used in conjunction with bootstrap techniques. RESULTS: By using multivariate analysis, percentage of epileptic EEG activity arising from the site of resection and either imaging localization or lack of use of invasive monitoring were the only statistically significant preoperative predictors for good outcome at 2 years. Presence of seizures within 2 months of surgery was a significant postoperative predictor for a poor outcome. Adding more variables did not result in significantly improved models. Use of validation techniques reduced the degree of optimism in the predictive value of the models. CONCLUSIONS: Pooling of data from multiple institutions is needed to attain the large sample sizes needed for multivariate analysis with validation.

Adolescent↗
PubMed1996

Multivariate analysis of prognostic factors in patients with endometrial cancer.

OBJECTIVE: The prognostic factors of endometrial cancer are closely correlated. A multivariate analysis was carried to compare the importance of each factor. METHOD: A multivariate analysis was performed of 19 clinicopathologic prognostic factors obtained from 144 endometrial cancer patients who had been surgically treated in our hospital between January 1971 and December 1993. RESULTS: Significant prognostic factors according to the Kaplan-Meier method were depth of invasion, vascular invasion, nuclear grade, cervical involvement, lymph node metastases, intraperitoneal cytology, serous adenocarcinoma, DNA ploidy, type of hysterectomy and surgery only or combined with chemotherapy or radiotherapy. Multivariate analysis showed that vascular invasion and nuclear grade were more significant than structural grade, histologic subtype or DNA ploidy. CONCLUSION: Multivariate analysis is useful for extracting important recurrent factors from mutually related prognostic factors. Vascular invasion and nuclear grade are singled out as the most useful histologic prognostic factors.

DNA, Neoplasm↗
PubMed1991

[Quantitative analysis of the teleost brain: evolutionary and adaptive characteristics of encephalization. III. Multivariate analysis of the cephalic index].

A multivariate analysis of 9 brain indices from 83 teleost species showed a marked opposition between the non-olfactory telencephalon (and diencephalon) and the medulla oblongata (phylogenetic characters) and between the olfactory bulbs and the optic tectum (adaptive characters). Results of three different classifying algorithms allowed determination of 6 stable groupings and 9 intermediate ones, some with systematic importance and some purely adaptive. For this reason brain organization criteria must be used with precaution for systematic purposes. Nevertheless, the position of Brotula multibarbata showed that this fish is an evolved acanthopterygian.

Adaptation, Physiological↗
PubMed2006

Changes in cod muscle proteins during frozen storage revealed by proteome analysis and multivariate data analysis.

Multivariate data analysis has been combined with proteomics to enhance the recovery of information from 2-DE of cod muscle proteins during different storage conditions. Proteins were extracted according to 11 different storage conditions and samples were resolved by 2-DE. Data generated by 2-DE was subjected to principal component analysis (PCA) and discriminant partial least squares regression (DPLSR). Applying PCA to 2-DE data revealed the samples to form groups according to frozen storage time, whereas differences due to different storage temperatures or chilled storage in modified atmosphere packing did not lead to distinct changes in protein pattern. Applying DPLSR to the 2-DE data enabled the selection of protein spots critical for differentiation between 3 and 6 months frozen storage with 12 months frozen storage. Some of these protein spots have been identified by MS/MS, revealing myosin light chain 1, 2 and 3, triose-phosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, aldolase A and two alpha-actin fragments, and a nuclease diphosphate kinase B fragment to change in concentration, during frozen storage. Application of proteomics, multivariate data analysis and MS/MS to analyse protein changes in cod muscle proteins during storage has revealed new knowledge on the issue and enables a better understanding of biochemical processes occurring.

Electrophoresis, Gel, Two-Dimensional↗
PubMed1993

Factors predicting chronic hepatic encephalopathy after distal splenorenal shunt: a multivariate analysis of clinical and hemodynamic variables.

BACKGROUND: This study was aimed at evaluating several factors that promote chronic hepatic encephalopathy by multivariate analysis of data for patients with cirrhosis with good or moderate liver function submitted to distal splenorenal shunts. METHODS: The study group comprised 131 patients: 55 had alcoholic and 76 nonalcoholic cirrhosis. Seventy patients were in Child's class A and 61 in class B. Cerebral function was assessed by a complete neurologic examination. Angiography with venous phase was performed before and within 1 month after the shunt operation. In 84 cases the original Warren technique was used and in 20 cases a Britton's modified procedure was used. Twenty-seven patients had distal splenorenal shunts with a splenopancreatic disconnection. Statistical analysis was performed by two multivariate analyses based on stepwise selection. RESULTS: Thirty-nine patients died during a follow-up period of 51 +/- 32 months. Chronic encephalopathy occurred in 18 patients (14%). According to the multivariate analysis of the preoperative prognostic factors, only age (p = 0.0001) and albumin values (p = 0.0002) were independent predictive risk factors for chronic encephalopathy. In the multivariate analysis concerning the hemodynamic consequences of the selective shunts, independent risk factors promoting chronic encephalopathy were postoperative portal perfusion (p = 0.0001), postshunt portal pressure (p = 0.001), and surgical disconnection (p = 0.0064). CONCLUSIONS: Our study has shown that chronic encephalopathy after selective shunt surgery is promoted by both clinical and hemodynamic factors. A better selection of the candidates for shunt surgery and prevention of the development of portal malcirculation by accurate surgical disconnection should further decrease the risk of chronic encephalopathy.

Actuarial Analysis↗
PubMed1988

Prognostic factors for survival in stage IIIB and IV Hodgkin's disease: a multivariate analysis comparing two specialist treatment centres.

A multivariate analysis of prognostic factors was carried out on 301 patients with clinical or pathological stage III/IV Hodgkin's disease treated using the same combination chemotherapy (MVPP) at two centres (Christie Hospital, Manchester, 151 patients, St. Bartholomew's Hospital, London, 150 patients). There were no significant difference in CR or relapse free and overall survival at 5 and 10 years between the two groups. Cox analysis of the Christie data alone produced four significant factors for survival - age, sex, lymphocyte count and stage. The latter three factors showed the same trend for the St. Bartholomew's Hospital patients but failed to reach statistical significance. Analysis of the combined data showed all four factors to be of importance in predicting survival. Three different prognostic groups were identified which separated patients with good, intermediate or poor prognosis in both centres. The good prognostic group included patients aged less than 45 years, lymphocyte count greater than 0.75 x 10(9) l-1 and female patients with stage IIIB disease (5 year survival 85%). The rest were of poorer prognosis with male stage IV patients faring particularly badly (5 year survival 40%). Problems associated with the use of multivariate analysis to produce useful prognostic groupings in patients from different centres, are discussed.

Age Factors↗
PubMed1988

A multivariate analysis of pathologic prognostic indicators in large bowel cancer.

A multivariate analysis of the pathologic data of 350 patients with primary colorectal cancer was performed. In addition to conventional parameters such as shape and size of the primary tumor, central node involvement, angioinvasive growth, grade, and stage, new variables such as the immunoreactivity patterns of carcinoembryonic antigen (CEA), CA 19-9, mucin, serotonin, secretory component (SC), and the DNA index were tested for their potential prognostic value. Every variable except CA 19-9, serotonin, and DNA showed significant prognostic information in univariate analysis. However, in the multivariate analysis stage was the predictive factor with the highest hazard ratio, but absence of central node involvement, tumors with diameters between 3.5 cm and 6 cm, exophytic tumor growth, well-differentiated tumors, tumors with CEA immunoreactivity, absence for staining with serotonin, and diploid tumors also were included in the relative risk model. Thus, the aforementioned variables appear to play a role in the establishment of a prognostic index.

Aged↗
PubMed2001

Clinical and demographic predictors of Barrett's esophagus among patients with gastroesophageal reflux disease: a multivariable analysis in veterans.

BACKGROUND: The subgroup of patients with gastroesophageal reflux disease (GERD) that should undergo endoscopy to rule out Barrett's esophagus (BE) has not been well defined. GOALS: To examine demographic and clinical variables predictive of BE before endoscopy. STUDY: A validated GERD questionnaire was administered to 107 patients with biopsy-proven BE and to 104 patients with GERD but no BE shown by endoscopy. Frequent symptoms were defined as symptoms that occurred at least once or more each week. Severity of symptoms was rated on a scale from 1 to 4 (mild to very severe). Univariate analysis and multivariable logistic regression were performed to determine whether demographic characteristics and the duration, severity, and frequency of GERD symptoms were associated with the identification of BE. RESULTS: Eighty-five percent of the GERD patients and 82% of the BE patients completed the questionnaire. There was no difference between the groups in terms of race, gender, or proton pump inhibitor use. The BE patients were older (median age, 64 vs. 57 years, p = 0.04). In multivariable logistic regression, an age of more than 40 years ( p = 0.008), the presence of heartburn or acid regurgitation ( p = 0.03), and heartburn more than once a week ( p = 0.007) were all independent predictors of the presence of BE. Interestingly, patients with BE were less likely to report severe GERD symptoms ( p = 0.0008) and nocturnal symptoms ( p = 0.03). Duration of symptoms, race, alcohol, and smoking history were not associated with BE. CONCLUSIONS: Upper endoscopy should be performed in GERD patients more than 40 years of age who report heartburn once or more per week. The severity of symptoms and the presence of nocturnal symptoms are not reliable indicators of the presence of BE.

Aged↗
PubMed2002

Evaluation of functional outcome of the floating knee injury using multivariate analysis.

INTRODUCTION: The objective of this study is to evaluate significant contributing factors affecting the functional prognosis of floating knee injuries using multivariate analysis. PATIENTS AND METHODS: A total of 68 floating knee injuries (67 patients) were treated at Kitasato University Hospital from 1986 to 1999. Both the femoral fractures and the tibial fractures were managed surgically by various methods. The functional results of these injuries were evaluated using the grading system of Karlström and Olerud. Follow-up periods ranged from 2 to 19 years (mean 50.2 months) after the original injury. We defined satisfactory (S) outcomes as those cases with excellent or good results and unsatisfactory (US) outcomes as those cases with acceptable or poor results. Logistic regression analysis was used as a multivariate analysis, and the dependent variables were defined as a satisfactory outcome or as an unsatisfactory outcome. The explanatory variables were predicting factors influencing the functional outcome such as age at trauma, gender, severity of soft-tissue injury in the femur and the tibia, AO fracture grade in the femur and the tibia, Fraser type (type I or type II), Injury Severity Score (ISS), and fixation time after injury (less than 1 week or more than 1 week) in the femur and the tibia. RESULTS: The final functional results were as follows: 25 cases had excellent results, 15 cases good results, 16 cases acceptable results, and 12 cases poor results. The predictive logistic regression equation was as follows: Log 1-p/p = 3.12-1.52 x Fraser type - 1.65 x severity of soft-tissue injury in the tibia - 1.31 x fixation time after injury in the tibia - 0.821 x AO fracture grade in the tibia + 1.025 x fixation time after injury in the femur - 0.687 x AO fracture grade in the femur ( p=0.01). Among the variables, Fraser type and the severity of soft-tissue injury in the tibia were significantly related to the final result. CONCLUSION: The multivariate analysis showed that both the involvement of the knee joint and the severity grade of soft-tissue injury in the tibia represented significant risk factors of poor outcome in floating knee injuries in this study.

Adolescent↗
PubMed1997

Multivariate analysis of prognostic factors in patients with ovarian cancer stage I and II.

OBJECTIVE: To evaluate prognostic factors such as surface capsular invasion, rupture of the capsule and intraperitoneal cytology in patients with stage I or II ovarian cancer. METHOD: Multivariate analysis was performed using 11 clinicopathologic prognostic factors obtained from 183 cases of stage I and II ovarian cancer, which had been surgically treated between 1983 and 1993. RESULTS: Significant prognostic factors determined by the Kaplan-Meier method were rupture and invasion of the capsule in stage II ovarian cancer. Multivariate analysis showed that spontaneous rupture of the capsule was the only significant factor, and intrapelvic cytology was an important factor without significance. Although capsular rupture caused by the surgeon showed poor prognosis by the Kaplan-Meier method, no significance was observed for this factor by multivariate analysis. CONCLUSION: Multivariate analysis showed that capsular rupture caused by the surgeon did not affect the prognosis in stage I and II ovarian cancer.

Adenocarcinoma↗