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PubMed1993

The predictive value of ERICA in breast cancer recurrence. A univariate and multivariate analysis.

In breast cancer, primary tumor size (T), the number of lymph node metastases (#N), the biochemical estrogen (ER), and progesterone (PGR) receptor status have all been important prognostic variables. We evaluated the significance of the immunocytochemical measurement of estrogen receptors suing the ERICA method. To determine the relative prognostic value of these variables T, #N, ER, PGR, ERICA and adjuvant treatment, (ADJ), univariate and multivariate analyses of disease-free survival (DFS) were performed for 154 primary breast cancer patients who were diagnosed in 1985 to 1986 at Women's College Hospital and followed prospectively. We analyzed ERICA results using different classification systems, and assessed clinical cut points for the univariate and multivariate context. The variables consistently included in the best Cox stepwise regression are T, (p < 0.01), ADJ (p < 0.01), #N (p < 0.01), and ERICA (p < 0.01). There was weaker evidence of an association between DFS and the biochemically determined ER; ER was not included in the model with a cut point at 10 fmol mg of protein. This illustrates the value of the ERICA method in predicting outcome, and suggests the need to consider ERICA values for clinical decision making.

Adult↗
PubMed1998

A multivariate analysis of the survival of patients with aggressive lymphoma: variations in the predictive value of prognostic factors during the course of the disease. Groupe d'Etudes des Lymphomes de l'Adulte.

BACKGROUND: Aggressive non-Hodgkin's lymphoma is now often curable with chemotherapy. The International Prognostic Index (IPI) was recently developed to predict patient survival on the basis of pretreatment clinical features. However, classical multivariate regression models such as the IPI fail to detect time-dependent changes in the predictive value of covariates. In this study, an extension of the Cox proportional hazards model was used to determine whether the value of prognostic factors might decay over time. METHODS: A total of 1271 patients younger than 60 years, entered on the LNH-84 and LNH-87 studies of an ACVBP induction regimen (consisting of doxorubicin, cyclophosphamide, vindesine, bleomycin, methylprednisolone, and IT methotrexate), were analyzed in terms of overall survival and monthly risk of dying. By a standard method, prognostic factors were identified in a training sample and confirmed in a validation sample. The independently significant covariates were then included in a step-function regression model (3-step) that permitted determination of their value in predicting the short term and long term survival of the entire population. RESULTS: During the entire follow-up period (median, 5.5 years), lactate dehydrogenase level, tumor stage, performance status, and number of extranodal sites remained independently predictive of overall survival. However, these covariates had nonproportional hazard functions. The study of their time-dependent effect with the 3-step model confirmed that they were predictive of overall survival during the short term follow-up period of 3 months to 2 years. However, during the induction period of 0-3 months and the long term follow-up period of 2-10 years, there was only 1 independently predictive factor for each of these periods: performance status and tumor stage, respectively. CONCLUSIONS: The IPI factors are relevant to short term follow-up and permit the selection of routine or experimental therapeutic regimens. In contrast, only performance status is predictive of a patient's ability to tolerate induction chemotherapy, and only tumor stage is predictive of long term survival.

Antineoplastic Agents↗
PubMedDate not supplied

Long-term follow-up and prognostic factors in Ewing's sarcoma. A multivariate analysis of 116 patients from a single institution.

The records of 116 patients from a single center (1970-1993) with newly diagnosed Ewing's sarcoma or primitive neuroectodermal tumor were reviewed retrospectively. The aim of this study was to ascertain the impact of pretreatment variables on disease-free survival. Median age was 14 years (range 1-34). Twenty patients presented with metastatic disease. Treatment consisted of systemic multiagent chemotherapy plus local irradiation (39%), wide resection (22%), or both (35%). Median potential follow-up was 10.7 years (range 2-26). Three patients developed second malignancies (1 breast carcinoma, 2 acute myeloid leukemias). Median time to relapse was 24 months (range 3-143). The actuarial disease-free survival was 37.4% at 5 years, 33.3% at 10 years and 27.8% at 15 years. Neoadjuvant chemotherapy and a therapy-induced tumor necrosis > or = 90% were associated with a better outcome. Patients undergoing surgical resection had a superior disease-free survival than those treated without surgery (45 vs. 18% at 10 years, p = 0.0009). Multiple regression analysis showed that raised serum lactate dehydrogenase levels (p < 0.001), hypoalbuminemia (p = 0.001) and distant metastases at diagnosis (p = 0.03) were independent adverse prognostic factors. In conclusion, one third of patients with Ewing's sarcoma become long-term survivors with combined modality treatment. Late relapses and second neoplasms are of concern. Prognostic factors should be considered in the selection of therapy, and the value of serum albumin warrants confirmatory studies.

Actuarial Analysis↗
PubMed1994

Clinical factors predicting persistence of activity in sarcoidosis: a multivariate analysis of 193 cases.

The prognosis of sarcoidosis is difficult to establish and it depends mainly on the persistence of activity over time and the degree of functional impairment of the involved organs. The aim of this study was to identify factors predicting persistence of disease activity at diagnosis. In a 14-year period (1974-1987), 209 patients were diagnosed with sarcoidosis at Bellvitge Hospital, a 1,000-bed teaching institution in Barcelona, Spain. One hundred ninety-three patients were followed up and included in the study. Clinical and radiological data were collected at diagnosis and a definition of disease activity was established. A Cox proportional-hazards regression model identified the following variables as independently influencing the persistence of activity: absence of erythema nodosum (risk ratio, RR = 2.37; 95% confidence interval, CI: 1.54-3.66), pulmonary infiltrates in chest x-ray (RR = 1.89, 95% CI: 1.28-2.8), splenomegaly (RR = 3.67, 95% CI: 1.46-9.23), age > or = 40 years (RR = 1.01, 95% CI: 1.006-1.03), and absence of lymphadenopathy in chest x-ray (RR = 2.26, 95% CI: 1.08-4.77). We suggest that the identification of factors predicting persistence of sarcoidosis activity at diagnosis may help to establish the prognosis of the disease and therefore improve the therapeutic approach.

Actuarial Analysis↗
PubMed2001

Multivariate analysis of prefrontal cortical data from the Stanley Foundation Neuropathology Consortium.

Prefrontal cortical tissue from the Stanley Foundation Neuropathology Consortium, which contains samples from patients with schizophrenia, bipolar disorder, non-psychotic depression, and normal controls (n = 15 per group), was studied in a blinded fashion in 14 different laboratories between 1997 and 2000. The results of 69 separate data sets were analyzed with univariate and multivariate techniques. A total of 17 abnormal markers were identified that pertained to a variety of neural systems and processes, including neuronal plasticity, neurotransmission, signal transduction, inhibitory interneuron function, and glial cells. Schizophrenia was associated with the largest number of abnormalities, many of which were also present in bipolar disorder. Major depression was associated with relatively few abnormalities. The majority of abnormal findings represented a decline in function and could not be easily explained by exposure to psychotropic or illicit drugs. It is argued that the abnormal findings are not simply due to stochastic processes but represent viable markers for independent replication and further study as candidate genes or targets for new treatments.

Adult↗
PubMed2001

[Cox multivariate analysis of prognosis and proposal on a modified staging system of thymoma].

OBJECTIVE: To investigate the clinicopathologic features, prognostic factors and propose a new modified staging criteria for thymoma. METHODS: The data of 159 patients operated for thymoma collected were retrospectively analyzed as to their prognostic factors and criteria of clinical staging through comparison of survival rates by the actuarial method, Log-rank and Cox multivariable model. RESULTS: Thorough resection (OR = 2.10), and extent of tumor invasion (OR = 1.73) were the most important prognostic factors. Tumor with peritumoral adhesion and absence of a complete capsule but without external invasion belonged to the criteria of stage II (II a). According to the prognosis and state of resection, lesions with obvious peritumoral invasion into the nearby organs but were thoroughly resected belonged to stage II (II b) and those incompletely resected belonged to III a. The unresectable lesions belonged to III b. CONCLUSION: According to the Cox prognostic multivariable model, the criteria of clinical staging of thymoma are defined as: Stage I-completely encapsulated non-invasive tumor without tight fibrous adhesions to the surroundings. Stage II a-only capsular invasion or capsule incomplete or with tight fibrous adhesions to the surroundings. II b-invasion into the surrounding fatty tissue, pleura, partial pericardium or lung, Stage III a-invasion into the great vessels, heart, trachea or hilus, which are resected with difficulty, or only palliatively. III b-extensive invasion into the nearby organs, and resection is impossible. Stage IV a-pleural or pericardial dissemination, IV b-lymphatic or hematogenous metastasis.

Adolescent↗
PubMed2001

Determinants of voiding after three types of incontinence surgery: a multivariable analysis.

OBJECTIVE: To determine the time to normal voiding in women after various surgical procedures for genuine stress urinary incontinence (GSUI) or urethral hypermobility. METHODS: One hundred one women had bladder neck suspensions. Suprapubic catheters were used in 94 women and intermittent self-catheterization in seven to manage urinary retention after surgery. We used a standardized protocol to record days to adequate postoperative voiding. Univariable and multivariable regression analyses were used to determine clinical, urodynamic, and surgical factors that independently influenced time to adequate postoperative voiding. RESULTS: Women met the criteria for adequate voiding a mean of 7.1 days after modified open Burch procedures (n = 43), 9.5 days after anterior colporrhaphies with suburethral plication (n = 24), and 19.1 days after vaginal wall sling procedures (n = 34). The type of bladder neck suspension was independently associated with increasing time to void (P =.001). Multivariable regression analysis determined other factors significantly associated with longer time to adequate postoperative voiding: advancing age, previous vaginal bladder neck suspension, increasing volume at first sensation on bladder filling, higher postvoid residual urine volume (preoperative), and postoperative cystitis. Detrusor pressure, abdominal straining on pressure flow voiding study, and other concurrent surgeries were not significantly associated with postoperative voiding time in this model. CONCLUSIONS: Time to adequate voiding after bladder neck suspension was influenced by type of surgical procedure, postoperative cystitis, and several demographic and urodynamic factors. This study does not support using pressure flow studies to predict women at risk of voiding dysfunction.

Adult↗
PubMed1998

Determinants of rifabutin-associated uveitis in patients treated with rifabutin, clarithromycin, and ethambutol for Mycobacterium avium complex bacteremia: a multivariate analysis. Canadian HIV Trials Network Protocol 010 Study Group.

Uveitis occurred in a substantial proportion of AIDS patients receiving rifabutin, 600 mg daily, together with clarithromycin and ethambutol for treatment of Mycobacterium avium complex bacteremia. A case-control study was undertaken to examine potential risk factors for developing uveitis. Of eight parameters examined, only baseline body weight predicted the development of uveitis by both univariate and multivariate analyses (P = .001). The incidence of uveitis was 14% in patients weighing >65 kg, 45% in patients between 55 and 65 kg, and 64% in patients <55 kg. Concomitant therapy with fluconazole, a drug known to raise serum rifabutin concentrations, was not associated with an increased incidence of uveitis. The risk of uveitis was markedly reduced when rifabutin was given at 300 mg daily in combination with clarithromycin and ethambutol.

AIDS-Related Opportunistic Infections↗
PubMed1998

Multivariate analysis of factors predictive of successful live births in in vitro fertilization (IVF) suggests strategies to improve IVF outcome.

PURPOSE: Our purpose was (1) to identify characteristics correlated with pregnancy outcome, (2) to use these characteristics to predict in vitro fertilization (IVF) outcome, and (3) to develop strategies that might improve IVF success. METHODS: Maternal age, cause for IVF, donor insemination, rank of attempt, serum estradiol and luteinizing hormone levels on the day of human chorionic gonadotropin administration, flexible vs rigid catheter, number of embryos transferred of each morphologic type, and cell number were analyzed by logistic regression. RESULTS: Variables positively correlated with success are as follows: (1) for pregnancy, endometriosis and 2-, 3-, and 4-cell good and 4-cell excellent embryos; (2) for live births, 2-, 3-, and 4-cell good and 4-cell excellent embryos and donor insemination; and (3) for multiple births, 2- and 4-cell good and 4-cell excellent embryos. Maternal age was negatively correlated with live births. CONCLUSIONS: Embryos derived from IVF have different potentials for implantation, live births, and multiple births. Transferring one additional good-quality embryo for each 5 years of incremental increase in maternal age is predicated to improve live birth rates without increasing multiple births.

Adult↗
PubMed1995

Multivariate analysis of fears in dental phobic patients according to a reduced FSS-II scale.

This study analyzed and assessed dimensions of a questionnaire developed to measure general fears and phobias. A previous factor analysis among 109 dental phobics had revealed a five-factor structure with 22 items and an explained total variance of 54%. The present study analyzed the same material using a multivariate statistical procedure (LISREL) to reveal structural latent variables. The LISREL analysis, based on the correlation matrix, yielded a chi-square of 216.6 with 195 degrees of freedom (P = 0.138) and showed a model with seven latent variables. One was a general fear factor correlated to all 22 items. The other six factors concerned "Illness & Death" (5 items), "Failures & Embarrassment" (5 items), "Social situations" (5 items), "Physical injuries" (4 items), "Animals & Natural phenomena" (4 items). One item (opposite sex) was included in both "Failures & Embarrassment" and "Social situations". The last factor, "Social interaction", combined all the items in "Failures & Embarrassment" and "Social situations" (9 items). In conclusion, this multivariate statistical analysis (LISREL) revealed and confirmed a factor structure similar to our previous study, but added two important dimensions not shown with a traditional factor analysis. This reduced FSS-II version measures general fears and phobias and may be used on a routine clinical basis as well as in dental phobia research.

Adult↗
PubMed1995

A multivariate analysis of factors related to the mortality of blunt trauma admissions to the North Staffordshire Hospital Centre.

OBJECTIVE: To identify characteristics of blunt trauma admissions associated with mortality and to derive a linear logistic model for predicting the probability of mortality. DESIGN: A prospective observational study. MATERIALS AND METHODS: Data were collected on blunt trauma patients admitted via the Accident and Emergency Department, North Staffordshire Hospital Centre. Univariate and multivariate analyses were performed of potential risk factors associated with mortality. MEASUREMENTS AND MAIN RESULTS: The main outcome variable was survival or death occurring in hospital within 30 days of admission. Injury Severity Score, age, Revised Trauma Score, and place of injury (road traffic, home, or elsewhere) were independently related to mortality. The effect of age on mortality was best described using three categories: 0-64 excluding 15-24, 15-24, 65+. The survival probability model suggests that a person whose injury occurs in the home has a lower probability of survival than a patient with similar age and trauma scores who is involved in a road traffic accident. A model validation check indicated good agreement between model predictions and patient outcomes. CONCLUSIONS: The authors propose that use of this model may provide a more accurate evaluation of the mortality of British trauma admissions than would be obtained using models based on data from American trauma cases.

Adolescent↗
PubMed2004

Multivariate analysis to separate the signal given by cross-reactants in immunoassay with sample matrix dilution.

This paper describes a new approach to achieve selectivity in an immunoassay by separating the signals given by two cross-reactive compounds present simultaneously in a complex sample matrix. The method is based on the sequential dilution of the sample containing a mixture of the two analytes, spiking each diluted sample with a reference compound, and the detection by enzyme-linked immunosorbent assay (ELISA). The obtained multivariate response was used for the individual calibrations of the assay for each of the two cross-reactants simultaneously by using principal component analysis (PCA) and partial least squares regression (PLSR) data modeling. The calibration models showed that the signal separation due the analytes 2,4-dinitrophenol (2,4-DNP) and 4-nitrophenol (4-NP) was possible with a prediction concentration error of 1.4 microM and 72 microM, respectively.

2,4-Dinitrophenol↗
PubMed2001

Multivariate prognostic analysis of stage I(E) primary non-Hodgkin's lymphomas of the nasal cavity.

From January 1968 to December 1997, a total of 71 patients with stage I(E) (Ann Arbor staging system, 1971) primary non-Hodgkin's lymphomas of the nasal cavity received treatment in the Cancer Center of Sun Yat-Sen University of Medical Sciences. Thirty-seven lesions were limited to the nasal cavity (limited I(E)), whereas the other 34 were extended to the structure out of the nasal cavity (extended I(E)). Forty-four patients were treated with radiochemotherapy and 27 with radiotherapy alone. Kaplan-Meier methods were used in the survival analysis. Multivariate analysis was carried out using the Cox proportional hazard model. The 5- and 10-year survival rates were 71.85% and 59.67% for the patients with a complete response to irradiation, and both were 13.89% for the patients with residue lesions (p = 0.0004). The 5- and 10-year survival rates were 69.81% and 56.72% for limited I(E), and 40.65% and 35.57% for extended I(E) (p = 0.0047). The prognosis was better for those younger than 44 years (p = 0.0003). The 10-year survival rates for radiotherapy alone and combined radiochemotherapy are 52% and 75% for limited I(E) versus 37.58% and 45% for extended I(E) (p = 0.0644). B symptoms did not significantly affect clinical outcome (p = 0.729). Multivariate analysis showed that complete response of local lesion after radiotherapy, invasion of the primary tumor to adjacent structures, and patients' age were independent prognostic factors. Our study showed that radiotherapy is the main treatment method for the primary non-Hodgkin's lymphomas of the nasal cavity; the addition of chemotherapy may improve long-term survival. The local tumor response to radiotherapy, whether the extranasal structures were invaded, and patients' age were independent prognostic factors.

Adolescent↗
PubMed1989

Prediction of clinical course and outcome in delusional psychoses. A multivariate analysis of a 4-year re-follow-up.

The purpose of the study was to examine the predictive value of clinical and socio-vocational variables of first-admitted patients with delusional psychoses as regards clinical course and outcome, which was illustrated by the dimensions: psychotic symptoms, impairment, remission, and relapse at a 4-year re-follow-up. An excess of patients had poor course and outcome. In the multivariate logistic analysis an independent statistically significant effect was assigned to male sex, low social group, few social contacts, no work, and long duration of psychosis. The most informative clinical and social predictors yielded a maximal information of 19-50% for the different dimensions of course and outcome. One-fifth of the patients had good outcome. Living with others and at the same time having frequent social contacts was a variable with an independent statistically significant effect. The most informative predictors of good outcome yielded a maximal information of 34%. Differences between predictors of 2-year and 4-year course and outcome are discussed. It is concluded that good prognosis is exceptional in patients with delusional psychoses and from a nosological approach attached to patients with reactive psychosis. However, socio-vocational variables at index admission are predictors of higher statistical information than any clinical variable.

Adolescent↗