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[Evaluation of clinical data and effort test in patients with angina pectoris: an approach to a multivariate analysis in different groups].

One-hundred and eighty-nine patients who underwent cardiac catheterization for suspected ischemic heart disease were assigned to four different groups depending on the number of diseased vessels (0, 1, 2, 3), the dominant artery and the presence of left main coronary stenosis. Among the 45 parameters obtained from history, physical examination, E.C.G., and exercise test multivariate analysis identified (positive stress test, maximal systolic blood pressure, documented myocardial infarction, maximal heart rate, ipercholesterolemia, lateral myocardial infarction, angina during stress test) that were statistically significant. A score system was devised on the basis of the summed-up value of the seven parameters. When the patients were assigned, according to the score, to one of the previously mentioned 4 groups, the classification proved to be correct in 54% of the cases. When we divided the patients in two groups with or without coronary artery disease so that the attribution turned out to be correct in 92% of the cases (sensitivity 94%, specificity 77%), whereas when based on ST segment depression only, the classification was correct in 85% of the cases (sensitivity 84%, specificity 88%).

Adult↗

Prognostic factors in retroperitoneal sarcoma: a multivariate analysis of a series of 165 patients of the French Cancer Center Federation Sarcoma Group.

BACKGROUND: Surgery is the main prognostic factor in retroperitoneal sarcoma. However, despite progress, surgery alone is rarely curative, and analysis of the causes of failures and of other prognostic factors are warranted to ascertain treatment orientations. METHODS: Data of patients treated from 1.80 to 12.94 for primary retroperitoneal sarcoma were extracted from the French Federation of Cancer Centers Sarcoma Group registry. Univariate and multivariate analysis were performed for initial local control and for local and general outcome. One hundred sixty-five patients (median age, 54 years; range, 16--82 years) were identified. Median tumor size was 15 cm (range, 2--70 cm); 31% of tumors presented with neurovascular or bone involvement. Liposarcoma, leiomyosarcoma, and malignant fibrous histiocytoma represented 66% of the tumors. Eighty-four percent of the tumors were of high or intermediate grade. Twenty patients had initial metastases. Multimodality treatment included surgery (150 patients), radiotherapy (92 patients), and chemotherapy (77 patients). Complete excision was achieved in 94 of 145 nonmetastatic patients. Median follow-up was 47 months (range, 3--160 months). RESULTS: Actuarial overall 5-year survival rate (median) was 46% (51 months). The main prognostic factors for survival were initial metastases and surgery, which represented the major treatment-linked factor. High-grade of tumors affected local recurrence, metastatic recurrence, and survival. Adjuvant radiotherapy was significantly associated with reduced local recurrence. Various evolutive patterns were observed with histologic subtypes. CONCLUSIONS: Aggressive surgery remains mandatory in retroperitoneal sarcoma, but a randomized trial is needed to evaluate the place of radiotherapy for local control.

Adolescent↗

Smoking during pregnancy and placental weight: a multivariate analysis on 3759 cases.

The analysis of a survey of 3759 births shows that the difference in placental weight between smokers and nonsmokers is, if not nil, at least minimal, and that is definitely less than might be expected taking birth weight and other factors into consideration in a multivariate analysis (Tab. II). The distortion between the fetal and placental weights, which are very closely correlated, assigns to smoking a peculiar place among the factors influencing these two weights, a result which may lead to various interpretations.

Analysis of Variance↗

Early function as the principal correlate of graft survival. A multivariate analysis of 200 cadaveric renal transplants treated with a protocol incorporating antilymphocyte globulin and cyclosporine.

We examined the factors determining graft survival in 200 consecutive cadaveric renal transplants managed on a quadruple-therapy protocol: Minnesota antilymphoblast globulin, cyclosporine, azathioprine, and low-dose prednisone. Perioperative central venous pressure monitoring and volume expansion were emphasized. To avoid CsA nephrotoxicity in the early posttransplant period, patients were treated with ALG until renal function was established (a mean of 7 days). Therapeutic CsA levels were achieved before ALG was discontinued. Azathioprine was used to supplement CsA in patients with nephrotoxicity or rejection. Twelve-month graft survival was 85% (first transplants 86%, retransplants 79%), with patient survival of 95%. ALG was not associated with excessive clinical cytomegalovirus infections, which occurred in 5% of patients, or with malignancy. When 3 technical failures were excluded, an analysis of numerous factors in the pretransplant and peritransplant period revealed that the strongest correlate of one-year graft survival was early renal function. Grafts with delayed function (DF) had 75% survival, compared with 91% for grafts with good early function (EF). A multivariate analysis confirmed this association: the relative risk of graft loss was increased 2.86 times for DF compared with EF. The mechanism of the deleterious effect of DF was apparently multifactorial: the DF group, by definition, contained all the kidneys that never functioned, but some risk also persisted in kidneys that achieved function. One reason for this may be that DF kidneys that achieved function had higher mean serum creatinine values at 1 month: elevated serum creatinine values at 1 month were strongly associated with increased risk of graft loss regardless of initial function. There was also a higher number of rejection episodes diagnosed in the DF group. These observations suggest that early renal function is a major determinant of graft outcome and should be a target for efforts to further improve renal graft survival.

Antilymphocyte Serum↗

A multivariate analysis of prognostic factors for melanoma patients with lesions greater than or equal to 3.65 mm in thickness. The importance of revealing alternative Cox models.

Fourteen prognostic factors were examined in 79 patients with clinical Stage I melanoma greater than or equal to 3.65 mm in thickness. All nine patients with melanoma of the hands or feet died of melanoma. A Cox proportional hazards (multivariate) analysis of the remaining 70 patients showed that a combination of the following four variables best predicted bony or visceral metastases: 1) a nearly absent or minimal lymphocyte response at the base of the tumor, 2) histologic type other than superficial spreading melanoma, 3) location on the trunk, and 4) positive nodes or no initial node dissection. Ulceration and/or ulceration width were not useful in predicting outcome either singly or in combination with other variables. Patients with negative lymph nodes and primary tumors of the trunk, hands, and feet did not do better than patients with positive nodes at those sites. Conversely, non of 16 patients with negative lymph nodes and extremity melanomas (excluding the hands and feet) or head and neck melanomas developed visceral or bony metastases (i.e., five-year disease-free survival rate 100%).

Adult↗

Prognostic factors in soft tissue sarcomas. A multivariate analysis of 109 cases.

Prognostic factors were evaluated in 109 soft tissue sarcomas of the extremities, walls of the trunk, head, and neck. All lesions were graded according to the systems proposed by the National Cancer Institute (NCI) and the French Federation of Cancer Centers (FNCLCC), and a correlation was found between tumor grade and prognosis. Univariate analysis selected the following variables as unfavorable prognostic factors: invasive tumor margins, extra-compartmental status, deep tumors, tumor diameters over 5 cm, inadequate excision, presence of necrosis, high mitotic count, histologically undifferentiated tumors, and blood vessel invasion. These variables were found to be interdependent. Multivariate analysis selected quality of surgery as the most important variable for predicting local recurrences. The factors selected with regard to overall and metastasis-free survival were tumor size, tumor margins, necrosis, and adequacy of excision. These results permitted classification of patients into four prognostic groups: two with good and two with bad prognosis. Five-year survival for the four groups was 100%, 83%, 53%, and 0%; 5-year metastatic rates were 0%, 12%, 67%, and 100%. Similar groups were obtained when the variables of tumor margins and size were combined with an adaptation of the NCI grading (low-grade tumors/high-grade tumors without necrosis/high-grade tumors with necrosis). Comparative analysis showed that patients with tumors of the same histologic grade or type were not necessarily classed in the same prognostic groups. A better clinicopathologic correlation was obtained using a combination of prognostic factors than with histologic grading or typing alone.

Adolescent↗

Spike separation in multiunit records: a multivariate analysis of spike descriptive parameters.

Variables describing unit discharges from multiunit extracellular records were treated, using multivariate statistical analysis for further automatic spike separation. A spike was described by 8 parameters (3 amplitude values, 3 time values and 2 slopes). These 8 parameters were summarized by 2 new independent factors, the principal components (PC). Examination of the 2 PCs from each spike allowed the observer to determine PC families corresponding to spike populations. From these the spikes were automatically classified. PC analysis showed groups of redundant parameters. Elimination of redundancy decreased the computing time without lowering the separation efficiency of the method. Three parameters turned out to be sufficient for spike discrimination: the maximum and the minimum amplitudes and the time between these. This agrees well with the physical basis of current propagation in the conducting medium, from the firing neurone to the recording electrode.

Action Potentials↗

Multivariate analysis of prognostic factors for curative resectable rectal cancer.

Several reports have shown that prognostic factors of rectal cancer are pathological parameters such as lymph node metastases, tumour infiltration, perineural and venous infiltration, and clinical parameters such as tumour level, mobility of the tumour and number of quadrants involved. From 1979 to 1983, 208 patients were treated curatively for rectal cancer in Montpellier Cancer Institute. A multivariate analysis was done to evaluate prognostic factors of our population. Prognosis was influenced by lymph node metastases, preoperative radiotherapy, tumour infiltration and histological type. The role of preoperative radiotherapy in local control and in survival appeared highly significant. Our results confirm the importance of external beam irradiation in local recurrence and in survival as shown randomly in the EORTC prospective trial. The growing trend in sphincter-saving surgery should be associated with preoperative radiotherapy.

Adult↗

Major sternal wound infection after open-heart surgery: a multivariate analysis of risk factors in 2,579 consecutive operative procedures.

From January, 1979, to December, 1984, at the Cardiac Surgery Department of the University of Torino Medical School, major sternal wound infections developed in 48 (1.86%) of 2,579 consecutive patients. These patients underwent open-heart procedures through a midline sternotomy and survived long enough for infection to appear. Possible risk factors were evaluated by means of a multivariate analysis. For the group of patients, we considered age, sex, hospital environment (different locations of our surgical facilities over the years), interval between hospital admission and operation, antibiotic prophylaxis, type of surgical procedure, elective or emergency surgical procedure, reoperation, duration of surgical procedures, duration of cardiopulmonary bypass, amount of blood transfused, postoperative blood loss, chest reexploration, rewiring of a sterile sternal dehiscence, duration of mechanical ventilation, and days of treatment in the intensive care unit. Univariate analysis indicated that age, sex, type and mode of surgical procedure, antibiotic prophylaxis, and duration of mechanical ventilation were not significantly associated with wound infection. For all other predisposing factors, a p value of less than .05 was demonstrated. These variables were entered in a multiple stepwise logistic regression. Six emerged as significant: hospital environment (p = .0001), interval between admission and surgery (p = .041), reoperation (p less than .0001), blood transfusions (p = .031), early chest reexploration (p less than .0001), and sternal rewiring (p less than .0001). Contamination of patients may occur before, during, and after operation, and any kind of reintervention may predispose to wound infection.

Cardiac Surgical Procedures↗

[Follicular thyroid cancer. A multivariate analysis].

The prognosis of malignant tumors is determined by a number of factors and their interaction. These factors may be assessed statistically by means of regression models for the hazard rates, which are assumed to be proportional. 89 follicular thyroid cancers from 1952 to 1975 were analysed according to clinical, macropathological and special histological criteria. Those variables which significantly influence the survival function were defined precisely and quantified by multivariate analysis. The age of the patients at the time of diagnosis (primary operation), sex, and local tumor extent (and therefore radical surgery) proved to be prognostically significant. Thus, the TNM system alone is sufficient neither for individual prognostic pronouncements nor for forming risk groups.

Adenocarcinoma↗

Prognostic factors in nodular lymphomas: a multivariate analysis based on the Princess Margaret Hospital experience.

A total of 1,394 patients with non-Hodgkin's lymphoma were treated at the Princess Margaret Hospital between January 1, 1967 and December 31, 1978. Overall actuarial survival of 525 patients with nodular lymphomas was 40% at 12 years; survival of patients with localized (Stage I & III) nodular lymphomas treated with radical radiation therapy was 58%. Significant prognostic factors defined by multivariate analysis included patient's age, stage, histology, tumor bulk, and presence of B symptoms. By combining prognostic factors we have identified distinct prognostic groups within the overall population. Patients with Stage I & II disease, small or medium bulk, less than 70 years of age achieved 92% 12 year actuarial survival and a 73% relapse-free rate in 12 years of follow-up. These patients represent groups highly curable with irradiation.

Adolescent↗

[Evaluation of radiation therapy of brain metastases from lung carcinoma using multivariate analysis].

A randomized clinical trial of whole brain irradiation for brain metastases arising from lung cancer is in progress to improve survival and the quality of life. Between September 1980 and July 1982, 40 patients were treated using 4 MV X-ray. Concerning the radiation dose, laboratory tests and the physical condition of the patients, we analyzed 22 data items by means of quantification II, one of the methods of multivariate analysis. We found that neurologic function, performance status and LDH are important factors in assessing the 120-day survival.

Adult↗

[Cancer of the rectum: treatment by a radiosurgical combination of 328 patients. Mono- and multivariate analysis of prognostic factors].

From 1973 to 1983, 328 patients have been treated for rectal carcinoma in the Centre Paul Lamarque by preoperative radiotherapy (40 Grays) followed by surgical excision. The average age was 64 years and the sex ratio was 2:1. Abdominoperineal resection was performed in 219 patients anterior resection in 99 patients and transanal resection in 10 patients. Overall 3 years survival was 82 p. 100 and 5 year survival was 73 p. 100. The five year local recurrence rate was 9.4 p. 100 with 3.5 p. 100 of patients having liver metastases. Monovariate analysis revealed that the local recurrence rate was influenced by tumor circumference (p = 0.005), tumor reduction after radiotherapy (p less than 0.001), histological type (p = 0.049), lymph node metastases and tumor infiltration (p = 0.001). Survival was influenced by lymph node metastases, tumor infiltration (p = 0.001) and histological type (p = 0.01). The multivariate analysis revealed that prognosis was influenced by lymph node metastases and tumor infiltration. The "down staging" induced by the radiotherapy did not modify the predictive value of these 2 prognostic parameters when compared to groups treated by surgery only.

Adult↗

[Chronic myeloid leukemia: multivariant analysis of initial findings regarding its effect on mean life expectancy].

Clinical signs, complete blood counts and bone marrow differential counts at the time of diagnosis were investigated in 75 consecutive patients with chronic myelogenous leukemia in a study of prognostic parameters. All patients were followed until death (62 patients) or for a mean follow-up time of 69 months (13 patients). Clinical signs and hematological values were analyzed by univariate and multivariate statistical methods. The only parameter relevant to mean survival time in multivariate analysis is the percentage of bone marrow myeloblasts at diagnosis. Patients with less than 5% myeloblasts at diagnosis had a mean survival time of 48 months compared with 16 months for those with greater than or equal to 5% (p less than 0.01).

Analysis of Variance↗

Effect of maternal age on blood loss during parturition: a retrospective multivariate analysis of 10,053 cases.

OBJECTIVE: An extensive study as to whether maternal age itself is a risk factor for blood loss during parturition. METHOD: A total of 10,053 consecutive women who delivered a singleton infant were studied. The excess blood loss was defined separately for women with vaginal and cesarean deliveries as > or = 90th centile value for each delivery mode. The effects of 13 potential risk factors on blood loss were analyzed using multivariate analysis. RESULTS: The 90th centile value of blood loss was 615 ml and 1,531 ml for women with vaginal and cesarean deliveries, respectively. A low lying placenta (odds ratio [OR], 4.4), previous cesarean (3.1), operative delivery (2.6), leiomyoma (1.9), primiparity (1.6), and maternal age > or = 35 years (1.5) were significant independent risk factors for excess blood loss in women with vaginal delivery. Placenta previa (6.3), leiomyoma (3.6), low lying placenta (3.3), and maternal age > or = 35 years (1.8) were significant independent risk factors for excess blood loss in women with cesarean sections. CONCLUSION: A maternal age of > or = 35 years was an independent risk factor for excess blood loss irrespective of the mode of delivery, even after adjusting for age-related complications such as leiomyoma, placenta previa, and low lying placenta.

Adult↗

Influence of water pressure on the final quality of arabica espresso coffee. Application of multivariate analysis.

Water pressure is one of the most important factors which influence the final quality of espresso coffee (EC). However, few studies dealing with this issue have been found. The aim of this work was to study the effect of water pressure on the final quality of Arabica ECs as well as to classify ECs prepared at different pressures (7, 9, and 11 atm) according to their physicochemical and sensory characteristics, key odorants, by means of multivariate analysis. Statistically, principal component 1 (PC1) separated ECs prepared at 7 and 9 atm from ECs prepared at 11 atm and included the main foam and taste characteristics as well as some key odorants and flavor compounds. ECs prepared at 7 and 9 atm were separated by principal component 2 (PC2). Coffees prepared at 9 atm showed consistency of foam and a high percentage of key odorants related to freshness and fruity, malty, and buttery flavors. A simple discriminate function was obtained by discriminate analysis, allowing the classification of ECs prepared at three pressures into their respective groups with a success rate of 100%.

Analysis of Variance↗

Husband or wife? A multivariate analysis of decision making for voluntary sterilization.

The increasing popularity of sterilization as a contraceptive choice among married couples underscores the need for knowledge about differences between couples choosing male and female procedures. Data from national surveys suggest some sociodemographic differences, but these variables account for only a small amount of the variance. This research looks at other sets of variables--information sources, influence sources, and reasons husbands and wives give for wanting sterilization--in a multivariate analysis of the choice of a male versus a female operation. Particularly for husbands obtaining a vasectomy, the importance of social support is demonstrated.

Behavior↗

Influence of mucinous components on survival in colorectal adenocarcinomas: a multivariate analysis.

Of 534 resected colorectal adenocarcinomas, 165 (31%) contained some mucinous components; these represented the main part of the tumour in 67 (13%). Of the mucin containing tumours, 63 (38%) were in the right colon compared with 50 (13%) of the non-mucinous ones (p less than 0.001). Patients with predominantly mucinous tumours were significantly older than those with non-mucinous tumours, and they tended to present with tumours at a more advanced stage. A multivariate analysis did not show any significant independent prognostic influence of the mucinous component except when this had a predominantly signet ring cell pattern.

Adenocarcinoma↗