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At least 1,135 records · Page 63Linked to original sources
PubMed1995

Why do patients default from follow-up at a genitourinary clinic?: a multivariate analysis.

OBJECTIVE: Firstly to compare the proportion of patients defaulting from follow up at a genitourinary medicine clinic with those attending other hospital based clinics. Secondly to determine which factors are associated with non attendance at a city centre genitourinary medicine clinic. METHODOLOGY: The proportion of patients who defaulted at a genitourinary medicine clinic, a general medical clinic, a general surgical clinic and a dermatology clinic during March 1995 were compared. A multivariate logistic regression analysis was performed comparing attenders and non attenders at the genitourinary medicine clinic with respect to time of appointment, diagnosis, previous contacts with clinic staff, potential domestic commitments and patient demographics in a prospective case control study. RESULTS: The default rate at the genitourinary medicine clinic was 15% compared with 13%, 15% and 14% for medical, surgical and dermatology clinics respectively. Patients who defaulted from the genitourinary medicine clinic (167) were compared with 172 attenders and significant differences found for timing of appointments, area of residence, frequency of counselling by the health advisor and age of the patient. Other factors such as the diagnosis, whether a woman had children, sexual orientation, whether negative results had been given over the phone, source of referral, sex of patient, employment status and the weather were not found to be significantly associated with defaulting from an appointment. CONCLUSIONS: The time of the appointment and being seen by a health advisor were the only variables identified over which the clinic has control and therefore could potentially reduce non attendance rates.

Adult↗
PubMed1987

Multivariate analysis of risk factors for metastasis in retinoblastoma treated by enucleation.

Retinoblastoma, when it kills by metastasis, almost always does so within 5 years of enucleation. The median time to death was 6.4 months in unilateral cases and 14.2 months in bilateral cases. Multivariate statistical analysis of 361 cases of retinoblastoma indicated that histologic detection of invasion of the tumor into the optic nerve or orbit were the risk factors most highly predictive of death from retinoblastoma. Choroidal invasion was not significantly associated with a fatal outcome. Histologic evidence of a cataract, failure to diagnose retinoblastoma clinically, and bilaterality were also significant risk factors. The authors believe that in at least two of the cases of bilateral retinoblastoma death did not result from metastasis to the brain as was originally diagnosed, but resulted from the development of an independent primary intracranial neuroblastic tumor, a syndrome designated "trilateral retinoblastoma."

Cataract↗
PubMed1994

Measuring feeding difficulty in patients with dementia: multivariate analysis of feeding problems, nursing intervention and indicators of feeding difficulty.

The feeding difficulty of 196 elderly people with dementia was investigated by means of an 11-item questionnaire administered to nursing staff. The questionnaire was analysed by means of multivariate statistics, namely factor analysis. The factor analysis demonstrated that the original items could be reduced to three factors. These three factors were named: (a) patient obstinacy or passivity; (b) nursing intervention; and (c) indicator of feeding difficulty. This quantitative analysis confirms a previous qualitative distinction between items in the questionnaire and suggests avenues of research into the relationship between the factors.

Aged↗
PubMed1984

Multivariate analysis of factors associated with outcome of treatment for adults with acute myelogenous leukemia.

Utilizing multivariate logistic regression statistical analysis, the authors evaluated prognostic features associated with achievement of complete remission (CR) and remission and survival duration in acute myelogenous leukemia (AML). These clinical variables were analyzed in 77 consecutive adult patients who underwent 108 courses of remission induction therapy with daunomycin, cytosine arabinoside, and 6-thioguanine (DAT) chemotherapy for newly diagnosed and first relapse of AML. Eight patients had developed leukemia in the setting of other malignant or immunologic diseases (therapy-linked AML) and 69 patients had not (primary AML). Sixty-three percent of patients with primary AML achieved CR with median remission and survival durations of 11 and 24 months, respectively. Significant unfavorable predictive features for achievement of CR were splenomegaly, and elevated leukocyte count or serum alkaline phosphatase levels. Patients who had leukocyte counts of less than or equal to 10,000/mm3 at diagnosis or less than or equal to 40,000/mm3 at the start of therapy, and those who received greater than 120 mg/m2 of daunomycin had significantly longer remissions and survival than those who did not. Fifty-seven percent of patients in first relapse also achieved CR; however, relative to first remissions, second remission durations were significantly shorter (median, 4.6 months). Sixty-two percent of patients with therapy-linked AML achieved CR, but remission durations (median, 2.8 months) were significantly shorter than first remissions of primary AML patients. These data identify clinical features associated with increased risk of failure to achieve CR and potential for short remission duration and survival. Alternative forms of therapy should be considered for such high-risk patients.

Adolescent↗
PubMed1996

Taxonomy of nuclear receptors and SERPINS by multivariate analysis of amino-acid composition.

The global amino-acid composition of a protein, although a cruder variable than sequence, is nevertheless informative and has been correlated with protein structural class. In the present study, we have applied complementary multivariate methods based on chi 2-metrics (correspondence factor analysis (CFA), minimum spanning tree (MST), ascending hierarchical classification (AHC)) to the analysis of the amino-acid frequency patterns of the C-terminal domain of 39 members of the nuclear receptor superfamily. The correlations we observed among receptors by this simple approach were, with few exceptions, in line with published phylogenetic dendrograms derived by sequence alignment. Further multivariate analyses were performed on the receptor population combined with 26 serine protease inhibitors (SERPINS) in view of the analogies detected between these superfamilies by hydrophobic cluster analysis (HCA), which were at the origin of the choice of alpha 1-antitrypsin as a 3-dimensional (3D) model for the receptor hormone-binding domain. Both the MST and AHC identified two distinct protein populations which in the principal phi 1 phi 2 CFA plot showed virtually no overlap, thus suggesting that receptors and SERPINS have different overall folding patterns, although the lower-order phi 3 phi 4 plot did reveal some similarities, essentially in the use of hydrophobic amino acids, that might account for analogies in HCA patterns. Receptors had a preference for those amino acids that are more frequent in alpha-helices and SERPINS for those in beta-strands and also tended to use different amino acids in turns. We therefore propose that multivariate analysis of amino-acid composition may prove helpful in identifying proteins for subsequent HCA.

Amino Acids↗
PubMed1998

Predictive factors for late toxicity after endobronchial brachytherapy: a multivariate analysis.

PURPOSE: To determine the predictive factors associated with hemoptysis and radiation bronchitis after endobronchial brachytherapy by univariate and multivariate analyses METHODS AND MATERIALS: One hundred forty-nine patients underwent endobronchial brachytherapy and were divided into three therapeutic groups: group 1: patients treated with palliative intent (n=47); group 2: patients treated with curative intent (small endobronchial tumors without mediastinal or general dissemination: n=73); group 3: patients also receiving external irradiation (n=29). One hundred twelve patients had previously received external irradiation. Brachytherapy was delivered with a dose per fraction ranging from 4 to 7 Gy and a prescription point between 0.5 and 1.5 cm, usually 1 cm from the source center. Two to six fractions were delivered according to the therapeutic group and clinical situation. The influence of the following variables on the incidence of hemoptysis or radiation bronchitis was studied: age, sex, Karnofsky score, therapeutic group, histologic type, endoscopic tumor length, dose per fraction, total brachytherapy dose, total external beam irradiation dose, total dose (brachytherapy dose plus external irradiation dose), volumes of the 100% and 200% isodoses, and volumes of the 7 and 14 Gy isodoses. RESULTS: We observed 11 hemoptyses (7.4%), 10 were lethal. All but one occurred in patients with progressive disease. Two clinical factors were significantly associated with hemoptysis by univariate analysis: palliative group (p=0.009) and endobronchial tumor length (p=0.004). No technical factors seem to be implicated in the occurrence of hemoptysis. Only endobronchial tumor length remained in the multivariate model (p=0.02). Radiation bronchitis was observed in 13 cases (8.7%). By univariate analysis, a good Karnofsky score (p=0.02), curative treatment (p=0.02), and tumor location on trachea and main stem bronchus (p=0.002) were significantly associated with this complication. Two technical factors were also incriminated: the total dose (p=0.04) and the 100% isodose volume (p=0.02). By multivariate analysis, only the tumor location retained statistical significance (p=0.009). CONCLUSION: Hemoptysis is most likely due to disease progression, with the bleeding being facilitated by brachytherapy. Some rare cases could be a direct complication of brachytherapy itself, particularly when tumors are located in the upper lobes. In contrast, radiation bronchitis occurred more frequently in patients with controlled disease, and was significantly influenced by tumor location and technical factors (dose and volumes treated). Technical improvements should increase the therapeutic ratio.

Analysis of Variance↗
PubMed1999

Multivariate analysis of metal concentration profiles in mushrooms.

The present work is an overview of the levels of contamination of 92 macromycetes by 15 metals. Data were collected around Paris (France) in 1989 and 1990. A progressive approach involving the use of univariate followed by multivariate statistical analyses allowed to fully exploit the resulting data matrix. Thus, conclusions regarding the origin of the metals, the toxicological implications and the possible use of mushrooms as environmental markers of pollutions are drawn.

Ascomycota↗
PubMedDate not supplied

Renal cortical retention of contrast medium after angiography as assessed by delayed CT: a multivariate analysis.

Renal cortical retention (RCR) of contrast medium discovered by delayed X-ray examination is sometimes reported in patients with problems in the urinary system. However, we frequently found RCR even in patients with normal renal function. Therefore, we examined the incidence and factors involved in RCR by delayed computed tomography (CT) 12-24 hours after angiography in 168 patients. RCR was found in 80 of 168 cases (48%). Ioxaglate (60%) and iohexol (60%) showed higher incidences of RCR than diatrizoate (37%) and iopamidol (37%). Multivariate logistic regression analysis was performed to determine the predisposing factors of RCR. Dose of administered contrast medium by body weight (p = 0.004), age (p = 0.009), sex (p = 0.013), type of contrast medium (p = 0.003), serum albumin (p = 0.011), and serum creatinine (p = 0.002) were identified as significant and independent predisposing factors of RCR. We suggest that RCR is not a rare phenomenon if delayed CT is carried out.

Adolescent↗
PubMed1993

A multivariate analysis of disability and health, and its change over time in the National Channeling Demonstration data.

The Channeling Demonstration examined the effects of case management interventions on a variety of outcomes. In the study, longitudinal data were collected from interviews of cases and controls. A multivariate procedure applied to this data identified groups with specific health profiles. Six profiles described health variation over individuals, and time, according to likelihood ratio statistics. Six sets of life tables were calculated, one for each health profile, to estimate the average duration of service use and the "follow-up" services used. A number of differences, and changes, in service use between the six groups were significant.

Activities of Daily Living↗
PubMed1993

Interactive multivariate analysis of bisindolylmaleimides as potent protein kinase C antagonists.

The isoenzyme protein kinase C (PKC) inhibitory activity of substituted bisindolylmaleimides depends on the molecular weight, the total charge, and dipole moments. The validity of the resulting QSAR equation was investigated by interactive diagnostic statistics and multivariate simultaneous statistical inference. Molecular mechanics and dynamics can be used to study possible reasons of flagged observations (high-leverage points, influential data, outliers) of QSAR systems.

Maleimides↗
PubMedDate not supplied

Increasing efficiency and precision of data analysis: multivariate vs. univariate statistical techniques.

In deciding upon an appropriate analysis strategy during the planning phase of a research study, it is important to specify all of the independent and dependent variables to be included. From there, a technique should be chosen that will yield all of the information desired in the most efficient, precise, and powerful way. Frequently, the method of choice in nursing research will be a multivariate technique, since so many studies involve numerous variables whose effects on, or relationships with, other variables are of interest, as well as involving additional variables that should be taken into account for control or generalizability purposes. Not discussed in this paper, but worth mention, is the fact that all of these techniques involve various underlying assumptions (e.g., normality, homogeneity of variance, and independence in ANOVA) that must be met in order to use the techniques appropriately. If the assumptions are not met, the researcher might want to consider the use of nonparametric techniques--and there are both univariate and multivariate techniques available to choose from (Hollander & Wolfe, 1973; Siegel, 1956). The general advantages of a multivariate technique rather than separate univariate techniques would apply in terms of nonparametric statistics as well as parametric statistics. Increasing the accuracy, power, and efficiency of data analysis strategies should be a major concern to researchers.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1996

Postoperative complications after pneumonectomy for treatment of lung cancer: multivariate analysis.

The charts of 62 patients with primary lung cancer who underwent a pneumonectomy at our department from 1979 through 1992 were reviewed for the evaluation of postoperative morbidity and mortality. The 30-day mortality was 3/62 or 4.8%. Postoperative complication occurred in 37 of 62 patients (60%). The most common complication was a supraventricular tachyarrythmia. A major complication, which was defined as one necessitating re-thoracotomy or one which caused death, occurred in 19 patients (31%). We analyzed 43 perioperative variables for their predictive value of postoperative morbidity and mortality. Univariate analysis indicated that an elevated serum LDH, low predicted forced vital capacity, low predicted forced expiratory volume in 1 sec (FEV1) were significantly associated with the occurrence of a major complication. A multivariate logistic regression model indicated that a high LDH level, a low predicted FEV1 and no extubation following surgery were associated independently with a postoperative major complication. Since only the complete removal of a tumor offers a chance for cure for the treatment of non-small cell lung cancer, it is sometimes necessary to perform a pneumonectomy for these high-risk patients. Patients identified as being at high risk of a major complication should be candidates for intensive preoperative evaluation and perioperative care.

Adult↗