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Results for “Multivariate Analysis”

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At least 19 recordsLinked to original sources

PubMed1977

Changes of P50 in hypoxaemia, hypercapnia and polycythaemia: multivariate analysis.

Multivariate analysis of P50 changes in hypoxia, hypercapnia and polycythaemia was performed in an heterogeneous group of forty three patients: hypoxic subjects with or without hypercapnia, with or without polycythaemia and polycythaemic subjects without hypoxia. A statistical analysis was undertaken using comparison of the means, study of the correlations, principal component analysis, multiple regression and correspondence analysis. In the patients studied, P50 changes were not wholly explained by those of 2-3 DPG and pH; PaCO2, per se, did not play an important part. Haemoglobin concentration and P50 value would represent an adaptative mechanism to hypoxia: when hypoxia is moderate (80 greater than PaO2 greater than or equal to 65 torr) and isolated, oxygen haemoglobin affinity decreases (P50 increases); when hypoxia is severe (PaO2 less than 65 torr) and combined with hypercapnia and disturbed acid-base equilibrium, P50 comes back to normal range but haemoglobin increases, restoring thus, the normal blood oxygen content.

Adult↗

PubMed1991

Morphometry and classification of the cat hypothalamic capillaries using multivariate analysis.

Multivariate statistical methods were used to do morphological determination of the amount and the relation of the astrocytic foot processes (AF), astrocytic lamina (AL) and dense zones (DZ) on hypothalamic capillaries. We corroborated that 100% of the perivascular membrane is surrounded by glial astrocytic cytoplasm. Principal component analysis shows that the original variables are independent of one another. Cluster analysis confirms the individual situation obtained through the principal component analysis. Discriminant analysis shows that the discriminant capacity of the 3 variables is very significant. For the potential interrelations of astrocytic foot processes, astrocytic lamina and dense zones we have clearly differentiated four groups of hypothalamic capillaries.

Animals↗

PubMed1990

Empirical considerations in orthopaedic research design and data analysis. Part III: Multivariable analysis.

To make a contribution to a base of knowledge, research design must be sound and the data must be analyzed by the most efficient, powerful method available. In conducting orthopaedic research as well as when interpreting the orthopaedic literature, knowledge of multivariable analysis is essential in evaluating the effects of variables that may confound or influence the relationship of interest. An understanding of the basic tenets, underlying assumptions, and purposes of frequently used types of multivariable analysis is necessary for an accurate, critical evaluation of a study's results.

Humans↗

PubMed1990

[The analysis of prognostic factors for prostate cancer by multivariate analysis].

Multivariable analysis (quantification method I and II) was used to investigate the relationship between survival rates and prognostic factors. The items studied were age, stage, pathological differentiation, gait disturbance, acid phosphatase and erythrocyte sedimentation rate (ESR). The data were available for 353 patients for all items. The significance of each item was evaluated in all patients-group, subgroup stratified by their cause of death, and subgroup stratified by their stage. The significance of age and gait disturbance which represent the general condition was proven in all patients, non-cancer death group and stage ABC group. In the cancer death group, stage D group was the most significant as prognostic factor. ESR was the most significant in the stage D group and the significance was gradually increased with the observation time.

Humans↗

PubMed1992

Flow cytometric DNA analysis in Japanese colorectal cancer. A multivariate analysis.

Using Cox's proportional hazard model, we performed a multivariate analysis of survival data from 126 patients who underwent curative resection for colorectal cancer from 1971 to 1985. Flow cytometric DNA measurements were carried out using paraffin wax-embedded tissue blocks. Fifty-four per cent of the cases were found to be aneuploid and 46% were diploid. The depth of invasion of the tumor, nodal status, liver metastasis, peritoneal dissemination, DNA ploidy pattern, histology, macroscopic classification of the tumor, age, sex and site were tested in a survival analysis. The initial seven factors were found to be the significant prognostic variables in a univariate analysis. A multivariate analysis shows liver metastasis, DNA ploidy pattern and peritoneal dissemination as being the significant discriminants of survival (P = 0.0001, 0.0022, 0.0119, in this order). Therefore, nuclear DNA ploidy pattern in colorectal cancer is considered to be an independent prognostic factor.

Adult↗

PubMed1992

Predictors of dating violence: a multivariate analysis.

A multivariate approach was used to determine the pattern of predictors associated with engaging in dating violence. Predictors were selected whose relationship to dating violence has been established by earlier research: attitudes toward violence, sex-role attitudes, romantic jealousy, general levels of interpersonal aggression, verbal aggression, and verbal and physical aggression received from one's partner. Participants included 305 introductory psychology student volunteers (227 females and 78 males) who completed a set of scales related to dating relationships. Expecting different patterns of predictors to emerge for men and women, we performed separate multiple regression analyses for each. Of the set of predictors employed, receipt of physical violence from one's partner emerged as the largest predictor of expressed violence for both men and women. In addition, higher scores on attitudes toward violence and verbal aggression, and less traditional sex-role attitudes emerged as significant predictors of expressed violence for men. For women, less accepting attitudes toward violence, more traditional sex-role attitudes, feelings of romantic jealousy, higher general levels of interpersonal aggression, and verbal aggression were predictive of expressed violence. The implications of our findings for future research are discussed.

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↗

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↗

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↗

PubMed1991

Multivariate analysis of metastasis risk in laryngeal carcinoma. I. Tumor factors.

A multivariate analysis with a logistic regression model was performed in 181 cases of patients affected by laryngeal cancer, in order to evaluate the histologic tumor factors in predicting metastatic risk. The patterns used were: grading, localization, extension to the extralaryngeal structures, mode of growth. Nodal metastases are less influenced by the localization and the differentiation grade of the tumor. Cancer extended to the extralaryngeal tissues and with "infiltrating" type of growth are significantly correlated with nodal involvement. Multivariate analysis seems to be the best method to identify the exact value of each histological parameter used in prognosis of laryngeal carcinoma.

Carcinoma↗

PubMed1990

Improvement of diagnosis in the non-invasive assessment of coronary artery disease: enhanced evaluation of quantitative exercise 201thallium imaging by multivariate analysis.

STUDY OBJECTIVE: The aim was to evaluate discriminant analysis, performed in patients without prior myocardial infarction, in enhancing the diagnostic value of quantitative exercise 201thallium scintigraphy. DESIGN: All clinical, electrocardiographic, and scintigraphic variables were first subjected to a univariate analysis. Afterwards a discriminant analysis was done. PATIENTS: 135 patients (104 male) were studied. Age was 24-70 years, mean 55 years. MEASUREMENTS AND MAIN RESULTS: Two discriminant analyses were done. In the first analysis, the ability to detect the presence of coronary artery disease was tested. Significant variables were: (1) history of angina, (2) sex, (3) quantitative analysis of 201thallium scintigraphy, (4) age, (5) ischaemic ST response, (6) angina during the test, and (7) the pressure-rate product. The sensitivity, specificity, and accuracy of classification using the discriminant function were 91%, 87%, and 90%, respectively. The sensitivity was higher than when using only visual interpretation (sensitivity 70%; p less than 0.0002) or quantitative interpretation (sensitivity = 66%; p less than 0.0001) of thallium scans, without significant loss of specificity (p less than 0.5488; p less than 0.6875). In the second analysis, a discriminant function was calculated to detect multivessel disease. Five input variables were selected: (1) number of vessels with stenosis predicted by quantitative analysis, (2) number of vessels with stenosis predicted by visual analysis, (3) ischaemic ST response, (4) sex, (5) angina during the test. Multivariate analysis showed an increase in sensitivity when compared with visual interpretation (78% v 55%; p less than 0.0043) and quantitative analysis (66%; p less than 0.0156). Using the classification, the discriminant function was more accurate than visual analysis (81% v 69%) or quantitative analysis (77%). CONCLUSIONS: The results show that multivariate analysis of non-invasive test results in quantitative thallium exercise testing allows convenient use for clinical purposes with improved results.

Adult↗

PubMed1989

Prognostic factors in small cell lung cancer: multivariate analysis in the National Cancer Center Hospital (Japan).

Consecutive series involving 172 patients with small cell lung cancer were analyzed retrospectively using eight pretreatment and two treatment-related prognostic factors in respect of their influence on survival. All the patients received chemotherapy with or without chest irradiation, according to phase II or phase III trial protocols of the National Cancer Center Hospital, Tokyo, from 1970 to 1987. The influence on survival of the various factors was investigated using univariate methods and Cox's proportional hazards model. In patients who survived for more than one year, a performance status of 0-1, limited disease, an age greater than 60 years, the absence of liver metastasis, radiotherapy to primary site and response to chemotherapy were determined by univariate analysis to be favorable prognostic factors. By multivariate analysis, performance status (P = 0.005), age (P = 0.026) and response to induction chemotherapy (P = 0.0001) proved to be valuable prognostic survival factors. The extent of disease which had been considered one of the most significant prognostic factors, was shown not to be a significant independent variable by multivariate analysis. Staging procedures may influence the prognostic analysis. Although classifying the limited or extensive stage of disease is still recommended, the current staging system lacks stringency and may not, in fact, reflect the tumor burden accurately. A simpler and meaningful staging system needs to adopted universally in order to continue the build-up of data for comparison from all institutions.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1992

[Multivariate analysis of the clinical signs in late cortical cerebellar atrophy (LCCA) in Japan--compared with olivo-ponto-cerebellar atrophy (OPCA) and hereditary cortical cerebellar atrophy (HCCA)].

We investigated the clinical features of 179 patients with late cortical cerebellar atrophy (LCCA) comparing with 382 patients with olivo-ponto-cerebellar atrophy (OPCA) and 91 patients with hereditary cortical cerebellar atrophy (HCCA) using multivariate analysis. They had no significant difference in durations from onset. Disorders of finger-nose test were of more severity and disorders of heel-knee test were less involved in LCCA than in HCCA. Eye movements tended to be normal in LCCA. LCCA showed more depressive and euphoric character than OPCA and HCCA. Analysis of LCCA and OPCA demonstrated that LCCA revealed hypotonia in muscles, normal or weak reactions of muscle stretch reflexes. There existed 21.4 percent of cases which could not be discriminated by multivariate analysis using clinical signs in LCCA and OPCA. Multivariate analysis of LCCA and HCCA, which are very similar in clinical signs, showed 66.3 percent of discriminatory rate. Thus, we could diagnose them to a certain extent only by clinical signs.

Aged↗

PubMed1989

Multivariate analysis of prognostic factors in pediatric and adult thalamic and brainstem tumors.

A multivariate analysis of prognostic variables was performed on a retrospective review of 136 patients with presumed or histologically proven primary lesions of the thalamus and brainstem treated by combined surgery and post-operative irradiation or by irradiation alone from January 1950 through December 1983. Overall survival for all patients at 5 and 10 years was 34.4 and 27.8%, respectively. Follow-up of 33 living patients ranged from 3 to 22 years. Prognostic variables analyzed by univariate analysis and found to be of significance (p less than 0.05) were race, duration of symptoms, extent of surgery (i.e. subtotal excision), and dose of irradiation. Further evaluation by Cox regression analysis revealed these same factors to be of prognostic significance (p less than 0.05). It is of importance to note that age and tumor site were not significant prognostic variables in the multivariate analysis but were significant by univariate analysis. The 5-year overall survival for patients with thalamic tumors was 59.5 and 20.9% for children and adults, respectively (p = 0.006). The 5-year overall survival for patients with pontine lesions was 46.6 and 16.0% for adults and children, respectively (p = 0.01). Only one patient was known to have expired due to a complication of therapy. Neurologic deficits and functional ability was normal or mild in 57.6% of the surviving patients.

Adolescent↗

PubMed1991

[Multivariate analysis for the prediction of recurrence in colorectal cancer].

We developed a predictive scale for cancer recurrence by conducting a multivariate analysis (Hayashi's discriminant analysis of qualitative data) on clinicopathologic indicators in 207 patients with Dukes' B or C colorectal cancer who underwent curative resection at our institution. Seven indicators were found to have prognostic value. Nodal status, which was divided into five categories according to the level and number of positive nodes, had the highest coefficient as a predictor of recurrence. The correlation ratio between the group showing recurrence and that showing non-recurrence was 0.49, with 74% discrimination success rate. Liver or lung metastases were more accurately discriminated than local or peritoneal failure. We assessed the accuracy of this predictive scale in 110 patients with Dukes' B or C colorectal cancer who had been surgically treated at another institution (National Cancer Center, Tokyo), and determined it to be 68%. We think that this scale using multivariate analysis for the prediction of cancer recurrence has significant clinical application in the selection of more effective postoperative adjuvant chemotherapy. It is concluded that the present predictive scale is clinically useful, but that the inclusion of other indicators such as immunohistological ones is required to increase its predictive precision.

Colorectal Neoplasms↗

PubMed1989

Prognostic factors in inflammatory breast cancer. Univariate and multivariate analysis.

Between 1958 and 1985, 107 patients with nonmetastatic inflammatory breast cancer (IBC) received radiotherapy as all or part of initial treatment at the Mallinckrodt Institute of Radiology. For this review, the diagnosis of IBC was made on the basis of either clinical or histopathologic criteria. Fifteen factors of potential prognostic significance were evaluated, by both univariate and multivariate analysis. For relapse-free survival, univariate analysis suggested prognostic value for initial tumor size, discrete versus diffuse tumor mass, adjuvant chemotherapy, and mastectomy. In the multivariate analysis, the independent prognostic factors, in order of significance, were mastectomy, diffuse versus discrete tumor mass, and race (marginal). For survival, univariate analysis suggested prognostic value for initial tumor size, diffuse versus discrete tumor mass, nodal stage, year of treatment, adjuvant chemotherapy, and mastectomy. In the multivariate analysis, the prognostic factors in order of significance were mastectomy and chemotherapy (marginal). The diagnostic selection group showed no prognostic value, suggesting that either clinical or histopathologic criteria justify the diagnosis of IBC. Our results appear to support a role for surgery as part of the combined modality approach to this disease.

Adult↗

PubMed1991

Recurrent and/or metastatic head and neck squamous cell carcinoma: a clinical, univariate and multivariate analysis of response and survival with cisplatin-based chemotherapy.

One hundred two patients with recurrent and/or metastatic head and neck squamous cell cancer were entered into four consecutive phase II trials, all cisplatinum (C-DDP, 100 mg/m2/cycle)-based. The two combinations tried were C-DDP, bleomycin, and fluorouracil (CFB) on 54 patients, and cisplatinum and vindesin in 36 patients (CV). The CFB combination was given with C-DDP by continuous infusion over 96 hours (23 patients) or on day 1 (31 patients). The CV regimen was also given in two different schedules, with VDS at 3 mg/m2/g weekly (12 patients) or by a 96-hour continuous infusion (0.6 to 1.0 mg/m2/d) in 24 patients. The following variables: sex, age, performance status, previous therapy, local recurrence, length of disease-free interval (DFI), distant metastases, weight loss, primary site, histological differentiation, type of chemotherapy, previous chemotherapy, evaluable/measurable disease, erythrosedimentation rate, and their relation with response to chemotherapy (WHO) and survival were submitted to both univariate and multivariate analysis (Cox). Overall response rate (RR:CR + PR) was 25 (28%) of 90. In the CFB protocols, RR was 12 (22%) of 54 vs. 13 (38%) of 36 (P = 0.15, NS) in the CV combination group. For the four different combinations the RR was CFB C-DDPci 7 (30%) of 23, CFB C-DDP 1 hour 5 (16%) of 31, CV VDS weekly 2 (17%) of 12, CV VDSci 11 (45%) of 24. The patient populations were very different, with the latest combination consisting of metastatic patients exclusively. Univariate analysis of multiple variables showed age less than 60 years, PS:0 or 1, no previous therapy, absence of local relapse, metastatic disease, long DFI, and that measurable disease was significant for the probability of response. Median survival was 7 months for the 90 evaluated patients, 5 months for nonresponders, and 9 months for responders (P = 0.01). In the univariate analysis, significant factors for survival were PS:0 or 1, a weight loss below 10%, long DFI, response to chemotherapy, erythrosedimentation rate (ESR) of less than 30 mm/1st hr, presence of bone metastasis, and the number of metastases. Multivariate analysis shows PS, the absence of local relapse, and disease-free interval as significant prognostic factors for response. Multivariate analysis factors of significance for survival were PS, weight loss, and response to chemotherapy. The analysis of the clinical pattern showed an evolution in RR from 3 (8%) of 36 on previously irradiated local recurrent disease to 8 (73%) of 11 in previously untreated patients with metastatic disease at presentation.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗