Search results for "STATISTICS"
showing 10 items of 7671 documents
Cancer net survival on registry data: use of the new unbiased Pohar-Perme estimator and magnitude of the bias with the classical methods
2013
Net survival, the survival which might occur if cancer was the only cause of death, is a major epidemiological indicator required for international or temporal comparisons. Recent findings have shown that all classical methods used for routine estimation of net survival from cancer-registry data, sometimes called "relative-survival methods," provide biased estimates. Meanwhile, an unbiased estimator, the Pohar-Perme estimator (PPE), was recently proposed. Using real data, we investigated the magnitude of the errors made by four "relative-survival" methods (Ederer I, Hakulinen, Ederer II and a univariable regression model) vs. PPE as reference and examined the influence of time of follow-up,…
HPV infection in relation to OSCC histological grading and TNM stage. Evalutation by traditional statistics and fuzzy logic model
2006
We aimed to evaluate if in oral squamous cell carcinoma (OSCC) there is a relationship between histological grading (HG), TNM clinical stage and HPV infection; and to study the performance of fuzzy logic compared to traditional statistics, in the analysis of HPV status and correlates of OSCC. In cross-sectional analysis, the study group comprised 63 patients (mean age 68.89 years (SD ± 11.78), range (32–93); males 28 (44.4%), females 35 (55.6%)) with OSCC histologically diagnosed. HPV-DNA was studied in exfoliated oral epithelial cells by nested PCR (MY09/MY11 and GP5+/GP6+ primers). Data were analysed in parallel by traditional statistics with multivariate analysis and a fuzzy logic (FL) t…
Evaluation of DNA ploidy and degree of DNA abnormality in benign and malignant melanocytic lesions of the skin using video imaging.
2000
BACKGROUND Making a morphologic distinction between benign and malignant melanocytic tumors of the skin is frequently difficult, especially because “gray zones” between these lesions often exist. DNA image cytometry as an adjuvant method for the diagnosis and prognostic prediction of premalignant lesions and malignant tumors of many other organs is already well established. The aim of this study was to determine whether DNA image cytometry is helpful in distinguishing benign from malignant melanocytic lesions and whether cytometry would give valid information with which to predict the prognoses associated with malignant melanomas. METHODS DNA image cytometry was performed on 127 benign and …
Comparison of prognostic models in patients with advanced Hodgkin disease
2001
Several prognostic systems have been elaborated for patients with Hodgkin disease (HD) over the last 12 years, but early identification of a reasonably large group of both low and high risk, advanced stage patients remains unsatisfactory.Seven well known models were applied to 516 patients with advanced HD, with 315 patients used for the study sample and 201 patients used for the test sample. Individual performances as well as joint performances were analyzed univariately and multivariately in relation to overall survival, recurrence free survival, and time to treatment failure by means of a proportional hazards model.None of the models identified a group containing10% of patients from the …
Cognitive and Motor Loops of the Human Cerebro-cerebellar System
2010
Abstract We applied fMRI and diffusion-weighted MRI to study the segregation of cognitive and motor functions in the human cerebro-cerebellar system. Our fMRI results show that a load increase in a nonverbal auditory working memory task is associated with enhanced brain activity in the parietal, dorsal premotor, and lateral prefrontal cortices and in lobules VII–VIII of the posterior cerebellum, whereas a sensory-motor control task activated the motor/somatosensory, medial prefrontal, and posterior cingulate cortices and lobules V/VI of the anterior cerebellum. The load-dependent activity in the crus I/II had a specific relationship with cognitive performance: This activity correlated negat…
The relationship of personality traits to substance abuse in patients with bipolar disorder
2007
AbstractPurposeThe aim of this study is to determine if personality traits contribute to the likelihood of substance abuse in Bipolar Disorder (BD).Subjects/materials and methodsFifty-nine patients meeting DSM-IV criteria for BD: 20 without any history of Substance Related Disorder (SRD), 21 with a lifetime history of SRD but without current SRD, and 18 with current SRD. Patients filled out the TCI, the differences were analyzed by ANOVA and the likelihood was obtained by Multinomial Logistic Regression.ResultsOnly Novelty Seeking (NS) is statistically different between the groups. Patients with BD with current SRD have higher rates in NS than those with past SRD, and those without a histor…
Effect of desquamative gingivitis on periodontal status: a pilot study
2009
OBJECTIVE: Desquamative gingivitis (DG) represents the gingival manifestation associated with several mucocutaneous disorders and systemic conditions. Little is known of whether or not DG could influence the onset or progression of plaque-related periodontitis. In this study, the potential impact of DG on plaque-related attachment loss and pocket formation has been evaluated. METHODS: A cross-sectional evaluation of 12 patients with DG [eight oral lichen planus (OLP), four mucous membrane pemphigoid (MMP)], never treated for DG lesions or plaque-related periodontitis, was carried out. Probing depth (PD), clinical attachment loss (CAL), fullmouth plaque (FMPS), and bleeding (FMBS) scores wer…
Anterior limbic alpha-like activity: a low resolution electromagnetic tomography study with lorazepam challenge
2005
Summary Objective To verify findings of an independently regulated anterior limbic alpha band source. Methods In a randomised cross-over study, the spontaneous EEG was recorded in nine healthy subjects after i.v. lorazepam or placebo. Intracerebral current densities within classical frequency bands were estimated with low resolution electromagnetic tomography [LORETA] and compared between groups with t -statistical parametric mapping [SPM{ t }]. A region-of-interest [ROI] based method was used to compare frontal and occipital alpha band activity changes. Results Irrespective of treatment group, local maxima of alpha band power were localised both in the occipital lobe, Brodman area [BA] 18,…
Task relevance and recognition of concealed information have different influences on electrodermal activity and event-related brain potentials.
2009
This study aimed at differentiating between memory- and task-related processes and their correlates on the electrodermal and electrocortical level during information concealment. Variations of the Guilty Knowledge Test were implemented in two experiments while we measured skin conductance responses (SCRs) and event-related brain potentials. P300 amplitudes were specifically enhanced for items requiring a deviant behavioral response but they were not sensitive to concealed knowledge. In contrast, N200 amplitudes differed between memorized and irrelevant items in both experiments. SCR measures reflected a combined influence of task relevance and probe recognition, and they provided incrementa…
Confirmatory Factor Analysis of the Valencia Scale of Attitudes and Beliefs Toward Hypnosis–client Version in a Portuguese Sample
2018
Research literature about hypnosis highlights the importance of clients' attitudes and beliefs toward hypnosis because they promote hypnotic responses and may predict the effectiveness of hypnotic interventions as well as minimize iatrogenic effects for clients. This study analyzes the factorial structure and psychometric properties with confirmatory methodology of the Valencia Scale of Attitudes and Beliefs Toward Hypnosis-Client Version, using a Portuguese sample. We expected to replicate the results obtained in previous research conducted with samples from various countries. The Portuguese sample comprised 1,977 participants. We found a structure of 8 factors, with an adequate internal c…