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PubMed1971

[Electrical picture of the brain under increased respiration in children. Studies on the structure of hyperventilation and its value as a provocation method in clinical electroencephalography in a model of multivariate analysis using electronic data processing].

In clinical electroencephalography, hyperventilation is the most used method of activation. However, knowledge of the conditions of hyperventilation with regard to their effects on the EEG is so far rather undifferentiated. For this reason the effects of hyperventilation in 1109 children are examined in this paper based on clinical and electroencephalographic parameters of a data configuration with a large number of criteria and the results obtained are calculated with the aid of electronic data processing. The statistical methods of examination were frequency and significance investigations by chi 2 tests, multifactorial analysis of variance, multiple regression analysis of influencing quantities, and determination of the reliability of the quantitative method of evaluation. New knowledge on group-statistical validity was obtained with this multivariant analysis and it was thus possible to extend the value of hyperventilation as a method of provocation in clinical electroencephalography. The increase in knowledge is based in particular on the facts that the hyperventilation effects are practically independent of sex, they do not require the consideration of certain age related development modalities of the EEG, they are diagnostically significant as regards unspecific changes of the bioelectrical activity, and they make a differentiated consideration with reference to their strength necessary, which results in 4 types of forms of changing the EEG spectrum. In addition to this, a recurrence of EEG changes was observed after the HV effect proper had faded, and the term "Reprise" is suggested for this and its clinico-encephalographic importance discussed. It was also found that occipital maxima dominate and that changes in frequency and amplitude require separate consideration. The influence of respiratory rate, tidal volume minute volume, alveolar CO2 tension, blood sugar and body weight on the strength of the effect of hyperventilation is not very significant. Mean controlled hyperventilation has proved useful to standardise arbitrary hyperventilation; an improvement could be achieved at the most by norming the respiratory rate. It was possible to prove that the applied method of non-mechanical quantitative EEG analyses had a high degree of accuracy and is consequently suitable for scientific investigations.

Adolescent↗

PubMed1997

The classification of benign and malignant human prostate tissue by multivariate analysis of 1H magnetic resonance spectra.

1H magnetic resonance spectroscopy studies (360 MHz) were performed on specimens of benign (n = 66) and malignant (n = 21) human prostate tissue from 50 patients, and the spectral data were subjected to multivariate analysis, specifically linear-discriminant analysis. On the basis of histopathological assessments, an overall classification accuracy of 96.6% was achieved, with a sensitivity of 100% and a specificity of 95.5% in classifying benign prostatic hyperplasia from prostatic cancer. Resonances due to citrate, glutamate, and taurine were among the six spectral subregions identified by our algorithm as having diagnostic potential. Significantly higher levels of citrate were observed in glandular than in stromal benign prostatic hyperplasia (P < 0.05). This method shows excellent promise for the possibility of in vivo assessment of prostate tissue by magnetic resonance.

Discriminant Analysis↗

PubMed1990

The risk of intracranial complications in pediatric head injury. Results of multivariate analysis.

Retrospective analysis of 12,072 pediatric head injury cases admitted to hospital revealed 159 patients with intracranial complications: 132 had intracranial hematoma and 27 had diffuse brain swelling. Multivariate analysis revealed two risk factors that could be recognized easily by primary-care physicians. They were found to be significant in predicting the development of intracranial complications. These risk factors were impairment of consciousness at the time of admission and clinical and/or radiological skull fracture. Analysis revealed that the combination of impaired consciousness and skull fracture carried the highest risk of complication (75%); however, the presence of impaired consciousness alone had an intermediate level of risk (19%). The presence of skull fracture alone carried a small overall risk (2%); however, this was highly dependent on age. The absence of all the risk factors considered carried a negligible risk of intracranial complications, provided proper skull X-rays were taken and correctly interpreted.

Adolescent↗

PubMed1995

Clinical and Histological Prognostic Factors in Axillary Node-Negative BreastCancer: Univariate and Multivariate Analysis with Relation to 5-Year Recurrence.

In the recent years several studies have shown that about 30% of cases with axillary node-nagative breast cancer suffer relapse of the disease. Our attempt was made to evaluate the most significant prognostic factors to predict this high risk group which may be benefited from adjuvant treatment. For this purpose, we selected 9 patients out of 80 cases of node-negative breast cancer who had been followed up at least for 5 years and had the recurrence of the disease. For comparison, 16 patients from the same group who did not have relapse were selected on a random basis. Histology, receptor status, AgNOR, DNA flow cytometry and various immunohistochemical parameters were compared between the groups with recurrence and that without recurrence. On univariate analysis, tumor size, immunohistochemical expressions of PCNA, MIB-1, c-erbB-2 and S-phase fraction were significantly different between the above two groups. By multivariate analysis, immunohistochemical c-erbB-2 expression (more than 50% of cancer cells) was an independent parameter. As a summary from our studies, c-erbB-2 immunohistochemical staining on paraffin sections might be the best independent prognostic factor in axillary node-negative breast cancers.

Journal Article↗

PubMed1986

Immunologic and cytogenetic studies improve prognosis prediction in chronic B-lymphocytic leukemia. A multivariate analysis of 24 variables.

Sixty patients with chronic B-lymphocytic leukemia (CLL) were studied. The prognosis predictions achieved from clinical and hematologic status, cytogenetic karyotype, immune phenotype, and cellular proliferative responses in vitro were studied by Cox's multivariate analysis. Indicators of poor survival were high dextran sulphate (DxS)-induced CLL-cell proliferation in vitro (P less than 0.002), older age, low percentage T-cells of blood lymphocytes (P less than 0.01), low hemoglobin count, advanced Binet stage, male sex, and high lymphocyte count (P less than 0.05). A therapy-demanding disease was predicted by cytogenetic data (extra chromosome 12, and complex karyotypes [P less than 0.001]), high DxS-induced CLL-cell proliferation (P less than 0.001), high frequency of cytogenetically abnormal metaphases, and advanced Rai and Binet stages (P less than 0.01). The best combinations of parameters included the cytogenetic variables, the DxS-induced CLL-cell proliferation, the relative T-cell number, and the Binet stage. Thus, results from immunologic and cytogenetic studies seem to be helpful in the prediction of prognosis.

Adult↗

PubMed1995

Factors associated with preterm birth in Cardiff, Wales. I. Univariable and multivariable analysis.

OBJECTIVE: Our purpose was to examine the associations of demographic, social, and medical factors with risk of preterm birth. STUDY DESIGN: By use of the Cardiff Births Survey, a large database of largely homogeneous (white) births in Wales, multivariable analysis by logistic regression examined the relative importance of risk variables associated with preterm birth. RESULTS: Significant independent associations with preterm birth were found (in decreasing order of magnitude) for late pregnancy bleeding, preeclampsia-proteinuria, low maternal weight, low maternal age, early pregnancy bleeding, history of previous stillbirth, smoking, high parity, low or high hemoglobin concentration, history of previous abortion, low social class, bacteriuria, and nulliparity. CONCLUSION: In this population demographic, social, and medical characteristics of the pregnancies showed significant associations with preterm birth.

Abortion, Induced↗

PubMed1994

Barrier precautions in trauma resuscitations: multivaried analysis of factors affecting use.

STUDY OBJECTIVES: To determine the relative importance of factors affecting use of barrier precautions by trauma team members. DESIGN: Prospective, nonblinded review of barrier precaution use by trauma team members over three periods. A multivaried analysis of factors affecting use then was conducted. SETTING: A 615-bed Level I trauma center in New York State with an accredited surgical residency program. TYPE OF PARTICIPANTS: Trauma team members involved in resuscitating multitrauma patients in the trauma room. INTERVENTIONS: Period 1: June to August 1991, barrier precaution use before interventions; period 2: September 1991 to January 1992, educational seminars held and material access improved by designated cart; period 3: February to June 1992, legislation mandating barrier precaution use introduced. MAIN RESULTS: Barrier precaution compliance improved significantly in periods 2 and 3. The improvement was seen in all providers studied. Improvement in barrier precaution use correlated significantly with education, materials access, and legislation. CONCLUSION: Improved compliance with barrier precaution use can be affected by education, improving materials access, and legislation. The relative importance of education versus materials access requires further study.

Cooperative Behavior↗

PubMed1984

Biochemical markers in non-Hodgkin's lymphoma stages III and IV and prognosis: a multivariate analysis.

The prognostic value of different pretreatment laboratory and clinical findings at diagnosis was assessed in a series of 141 patients with generalized non-Hodgkin's lymphoma. Univariate and multivariate survival analysis (Cox's regression model) was performed, using serum analysis of deoxythymidine kinase (S-TK), beta 2-microglobulin, lactic dehydrogenase, alpha 1-acid glycoprotein = orosomucoid (S-alpha 1 AGP), haptoglobin and ferritin. In addition, Hb and the erythrocyte sedimentation rate (ESR) were measured. The clinical variables were age, presence or absence of B-symptoms, histopathology ('low-grade'; 'intermediate grade' and 'high-grade' malignancy) and bone marrow involvement. Of the 8 biochemical markers, all except Hb and the ESR showed a significant relationship to survival. Among the clinical variables, this finding was made for B-symptoms and histopathology. Using a multivariate analysis on all variables, S-TK was found to be the best factor for predicting duration of survival. The only significant additional information was provided by S-alpha 1 AGP. When only the clinical variables were taken into account, it was found that histopathology added significant information to that yielded by B-symptoms in the prediction of the survival time. When the biochemical variables were added to this model, only S-TK was of significant additional prognostic value.

Adolescent↗

PubMed1975

Epidemiological evaluation of funduscopic findings in cerebrovascular diseases. II. A multivariate analysis of funduscopic findings.

The interrelationship of the funduscopic, physical and laboratory findings, the additional information of each funduscopic finding when physical and laboratory findings were considered simultaneously, and the relative importance of each retinal finding in the funduscopic pictures were investigated by a series of multivariate analysis for 68 cerebral hemorrhage, 47 cerebral thrombosis and 230 controls in two rural towns, Akabane and Asahi, in Japan and the results were as follows: 1. For the occurrence of cerebral hemorrhage, narrowing of arteriole and irregular constriction were especially important indicators, and retinal bleeding and lateral displacement were also valuable but less than narrowing and irregular constriction. On the other hand, for the occurrence of cerebral thrombosis, arteriolar reflex was considered as the most valuable indicator, and irregular constriction, lateral displacement and white plaque were also important but less than arteriolar reflex. 2. Narrowing of arteriole was most highly related with irregular constriction while the correlation between retinal bleeding and white plaque, and also the correlation between arteriolar reflex, vertical and lateral displacement and tapering were significant. 3. A significiant correlation among physical and laboratory findings was found only between systolic and diastolic blood pressure as far as analysed. Funduscopic findings by Scheie's hypertensive and Keith-Wagener's classifications were highly correlated with systolic and diastolic blood pressure. 4. Narrowing and irregular constriction were significantly correlated with systolic and diastolic blood pressure, and the relation between retinal bleeding and glycosuria was significant. 5. An analysis of the additional information of each funduscopic finding, when evaluated with the physical and laboratory findings simultaneously, revealed that irregular constriction, lateral displacement and narrowing gave prominent additional information for the occurrence of cerebral hemorrhage, while arteriolar reflex, lateral and vertical displacement and white plaque gave valuable information for the occurrence of cerebral thrombosis. 6. It is noteworthy from these multivariate analyses that narrowing and irregular constriction may arise from a similar pathophysiological mechanism which brings out vasoconstriction and the resultant organic changes due to hypertension. It is also noticed that arteriolar reflex and A/V crossing phenomenon may come from the different pathophysiological mechanism related to arteriosclerosis. It was stressed that detailed analyses of observer variability and evolution of funduscopic findings would be necessary.

Albuminuria↗

PubMed1985

Multivariate analysis of prognostic factors in chronic lymphocytic leukemia.

Prognostic factors in a group of 90 patients with chronic lymphocytic leukemia were studied by methods of survival analysis. The relationship between survival and a set of demographic, clinical and laboratory variables, and identification of subsets of variables that are associated with survival, was tested by multivariate analysis, which is based upon Cox proportional hazards regression models in a stepwise procedure. Six variables showed significant correlation with survival: lymph node enlargement, splenomegaly, hepatomegaly, increased percentage (greater than 80%) of lymphocytes, hyperuricemia, and anemia. Stepwise analysis showed that the number of coexistent risk factors was a better predictor of survival than any single risk marker (P less than 0.001). Median survival of patients with 0 or 1 risk marker was 120 months; with 2 or 3, 96 months; with 4, 36 months; and with 5 or 6, only 24 months. Comparison of staging by number of risk markers with staging of the same patients by the Rai system showed a significant trend of decreasing survival with increasing number of risk markers within the same Rai stage. Staging by the number of coexistent risk markers is a simple and readily available method, which may complement existing methods to provide a more accurate assessment of prognosis in patients with chronic lymphocytic leukemia.

Adult↗

PubMed1989

Determinants of end-stage idiopathic dilated cardiomyopathy: a multivariate analysis of 104 patients.

Our purpose in this study was to investigate the correlation of clinical, electrocardiographic, hemodynamic, and histopathologic features at diagnosis with the long-term prognosis in 104 patients with idiopathic dilated cardiomyopathy to determine which factors are the independent determinants of the end-stage disease. During a mean follow-up of 3.8 +/- 3.5 years, 35 patients (33%) died, 14 (13%) suddenly and 21 (20%) from congestive heart failure. Univariate analysis of survival curves disclosed that clinical and electrocardiographic variables at diagnosis were similar in survivors and non-survivors. On the contrary, patients who subsequently died had higher mean right atrial pressure (p = 0.0001), right ventricular end-diastolic pressure (p = 0.0061), mean pulmonary artery pressure (p = 0.0001), and left ventricular systolic (p = 0.0049) and end-diastolic (p = 0.0021) pressure than survivors. They also exhibited larger left ventricular end-diastolic (p = 0.0046) and end-systolic (p = 0.0027) volumes, lower ejection fraction (p = 0.0001), and a greater proportion had severe mitral regurgitation (p = 0.0095). Univariate analysis of histologic findings collected in a subgroup of patients referred since 1984 revealed a mild degree of myocellular hypertrophy to be associated with a poor prognosis (p = 0.0217). Multivariate analysis selected only mean right atrial pressure (p = 0.0022), ejection fraction (p = 0.0089), and end-systolic volume (p = 0.0265) as independent determinants of cardiac death. Our results suggest that cardiac catheterization is mandatory for risk stratification of patients with idiopathic dilated cardiomyopathy, since it allows the assessment of hemodynamic, angiographic, and histopathologic features helpful in identifying patients with a poor prognosis.

Adult↗

PubMed1981

Multivariate analysis of Drosophila courtship.

Courtship records of 15 pairs of Drosophila melanogaster were analyzed for temporal stationarity of courtship behaviors, behavioral diversity, behavioral intercorrelations, sequential properties, and information transmission for both sexes. Durations of one male behavior, "orient-back," and two female behaviors, "preen" and "stand still," were found to change from the first to the second half of courtship. Male diversity was greater than female diversity, and both were stationary over time. Correlation analyses failed to single out any particular male or female behaviors as being influential in controlling courtship duration. Male behavior sequences formed several multibehavior loops; female behavior consisted of only a few terminal two-tuple transitions. Transmission analysis carried out on the joint male/female transition matrix showed a higher transmission rate from males to females (12%) than from females to males (7%). Potential applications of this multivariate analysis to investigations of neurobiological and evolutionary aspects of Drosophila courtship behavior are proposed.

Journal Article↗

PubMed2002

Multivariate analysis of prognostic factors in CLL: clinical stage, IGVH gene mutational status, and loss or mutation of the p53 gene are independent prognostic factors.

This study evaluates the prognostic significance of genetic abnormalities (detected at or shortly after presentation), clinical stage, lymphocyte morphology, CD38 expression, and IGVH gene status in 205 patients with chronic lymphocytic leukemia (B-CLL). Deletion of chromosome 11q23, absence of a deletion of chromosome 13q14, atypical lymphocyte morphology, and more than 30% CD38 expression are significantly associated with the presence of unmutated IGVH genes. Advanced stage, male sex, atypical morphology, more than 30% CD38 expression, trisomy 12, deletion of chromosome 11q23, loss or mutation of the p53 gene, and unmutated IGVH genes are all poor prognostic factors in a univariate analysis. However, only 98% or more homology of IGVH genes to the germline sequence, loss or mutation of the p53 gene, and clinical stage retain prognostic significance in a multivariate analysis. The median survival of patients with mutated IGVH genes, unmutated IGVH genes, and loss or mutation of the p53 gene regardless of IGVH gene status is 310, 119, and 47 months, respectively. These data should facilitate the design of new trials for the management of patients presenting with advanced disease or poor prognosis early stage disease.

ADP-ribosyl Cyclase↗

PubMed1989

Factors influencing the development of gastrointestinal complications after neurosurgery: results of multivariate analysis.

A retrospective review of 526 patients who underwent neurosurgery for nontraumatic conditions over a 5-year period revealed 36 (6.8%) patients with endoscopically and or surgically documented postoperative gastrointestinal (GI) complications. Two patients had GI bleeding and perforation, and the remaining patients had bleeding only. Multivariate analysis indicated 5 factors that were of independent significance in predicting the development of postoperative GI complications. These factors included 1) inappropriate secretion of antidiuretic hormone, 2) preoperative coma (Glasgow Coma Score less than 9), 3) the presence of postoperative complications, 4) age greater than or equal to 60 years, and 5) pyogenic infection of the central nervous system. Further analysis of the 36 patients with GI complications revealed that they could be divided into three groups with different clinical courses. In Group I (n = 10), all patients died as a result of their neurological conditions; GI complications were just preterminal events and did not require treatment. In Groups II (n = 11) and III (n = 15), GI complications were symptomatic and life-threatening events, respectively. Eleven patients from Group III died as a direct result of the GI complications. Separate multivariate analyses based on the patients in Groups II and III revealed that preoperative coma was the only significant factor that predicted the occurrence of life-threatening complications. Patients who are at high risk of developing postoperative GI complications can thus be identified, and intensive prophylaxis may be instituted.

Brain Diseases↗

PubMedDate not supplied

Multivariate analysis of prognostic factors in fulminant hepatitis B.

We assessed prognostic factors in 115 patients with serologically defined fulminant hepatitis B. The diagnosis in each case was based on the finding of IgM antibody to the hepatitis B core antigen in serum. Multivariate analysis showed that factor V level (p less than 0.001), patient's age (p = 0.001), absence of detectable HBsAg by radioimmunoassay (p = 0.06) and serum alpha-fetoprotein concentration (p = 0.07) were independent predictors of survival. The survival rate in the 21 patients in whom HBsAg was not detected was 47%, which was significantly higher than the survival rate of 17% observed in the 94 HBsAg-positive patients (p = 0.006). In patients with fulminant hepatitis B, the absence of HBsAg in serum as detected by radioimmunoassay has an independent, favorable prognostic value.

Adolescent↗

PubMed1980

Multivariate analysis of the effects of manganese on the reproductive physiology and behavior of the male house mouse.

Chronic exposure to Mn3O4 in the diet at 1050 ppm Mn retarded the sexual development and lowered reactive locomotor activity levels in male mice. A multivariate analysis of variance indicated that testis, seminal vesicle, and preputial gland weights were significantly smaller as a result of Mn administration. These results support earlier observations of altered locomotor activity levels and reproductive development in male rats in the absence of other signs of toxicity.

Animals↗

PubMedDate not supplied

New mathematical statistical methods for detecting correct echocardiographic (ECG) and vectorcardiographic (VCG) diagnosis criteria by computerization. I. The determination of the upper (Lu) and low (Ll) limits for VCG amplitudes. The multivariate analysis.

The mathematical statistical methods for the determination of the upper (Lu) and low (Ll) limits of the 95 percentile range of symmetrical and asymmetrical frequency distribution curves for electrocardiographic (ECG) or vectorcardiographic (VCG) amplitudes, ECG and VCG diagnostic criteria, and the multivariate analysis as well as the bases of their computerization-program have been presented, in order to find out the ECG and VCG diagnostic criteria. The formulae for the determination of sensitivity, specificity and performance score of the ECG and VCG diagnostic criteria, in both the above mentioned methods are presented.

Analysis of Variance↗

PubMed2005

A problem in multivariate analysis of codon usage data and a possible solution.

Multivariate analyses are often used to identify major trends of variation in synonymous codon usage among genes. These analyses need to be performed on properly normalized codon usage data to avoid biases masking this synonymous variation, i.e., gene length, amino acid usage, and codon degeneracy; however, previous studies have failed to do so. In this paper, we demonstrate that the use of alternative normalized data (called 'relative adaptiveness' in the literature) can avoid all these biases and furthermore, can identify more trends of variation among genes, including GC-ending codon usage, GT-ending codon usage, and gene expression level.

Amino Acids↗