Search results for "Stepwise regression"

2019

The etiology of overweight and obesity is a mixture of genetic determinants, environmental factors and health behaviors. Especially intra- and interpersonal inactive behaviors, here termed convenience seems to play an important role. The objective was to develop and validate the Convenience Behavior Questionnaire (CBQ) to assess convenience-related items and their association with overweight and obesity in a large population. A sample of 1233 subjects aged 18 to 82 years from six population groups took part in a self-administered questionnaire. Test-retest reliability was estimated and the independent association between convenience-related items and overweight and obesity was investigated.…

Comparison of the roles of common constitutional and behavioural parameters in back performance estimates

2006

Objective: To compare the associations between different physical activity histories and anthropometric measures in isokinetic lifting performance, isometric back extension endurance and psychophysical lifting tests. Background: The relative roles and interaction of these factors related to back function are largely unknown. Methods: The subjects consisted of a population-based sample of 210 working-age males. Paraspinal muscle cross-sectional areas were obtained by magnetic resonance imaging; anthropometric measures, isokinetic and psychophysical lifting capacity, and isometric back extension endurance tests were performed and current and physical activity histories and occupational loadin…

2018

Purpose: Few large-scale population-based studies have adequately examined the relationships between steroid hormones, health status and physical fitness. The purpose of the study was to describe the relationship of serum basal endogenous steroid hormones (testosterone, TES; empirical free testosterone, EFT; cortisol, COR) and sex hormone-binding globulin (SHBG) to body composition, cardiovascular risk factors, and physical fitness in young healthy men. Methods: Male reservists (25±4 yrs, N=846) participated in the study. Basal TES, EFT, COR and SHBG were measured in morning fasted blood. Stepwise regression analyses were used to examine associations between individual hormones to four sepa…

Biomass Assessment of Agricultural Crops Using Multi-temporal Dual-Polarimetric TerraSAR-X Data

2019

The biomass of three agricultural crops, winter wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and canola (Brassica napus L.), was studied using multi-temporal dual-polarimetric TerraSAR-X data. The radar backscattering coefficient sigma nought of the two polarization channels HH and VV was extracted from the satellite images. Subsequently, combinations of HH and VV polarizations were calculated (e.g. HH/VV, HH + VV, HH × VV) to establish relationships between SAR data and the fresh and dry biomass of each crop type using multiple stepwise regression. Additionally, the semi-empirical water cloud model (WCM) was used to account for the effect of crop biomass on radar backscatter …

Examining the Veggiee Personality: Results from a Representative German Sample

2017

An increasing proportion of people choose to follow a vegetarian diet. To date, however, little is known about if and how individual differences in personality relate to following a vegetarian diet. In the two studies presented here, we aimed to (1) estimate the prevalence of self-defined vegetarians in two waves of a German representative sample (N = 4,496 and 5,125, respectively), (2) analyze the effect of socio-demographic variables on dietary behavior, and (3) examine individual differences between vegetarians and meat eaters in personality traits, political attitudes, and health-related variables. In Study 1, a strict definition of vegetarians was used, while in Study 2 the definition …

Interaction of cerebrovascular disease and contralateral carotid occlusion in prediction of shunt insertion during carotid endarterectomy

2012

INTRODUCTION To assess the possible role and the interaction of cerebrovascular disease and vascular stenosis on the necessity of shunt insertion during carotid endarterectomy (CEA). MATERIAL AND METHODS Eighty consecutive patients undergoing CEA under regional anaesthesia were prospectively enrolled. Patients were divided into two groups depending on whether they were shunted or not. The measured end-points were co-morbidities degree of contralateral and carotid stenosis and other intra- and postoperative outstanding parameters. ANOVA, Student's t and χ(2) tests were used (p<0.05). Variables differing significantly between groups and potential confounders were used in backward stepwise log…

Heart Rate Is a Better Predictor of Cardiorespiratory Fitness Than Heart Rate Variability in Overweight/Obese Children: The ActiveBrains Project

2019

The authors would like to thank all the participants who volunteered for this investigation. This work is part of a Ph.D. thesis conducted in the Biomedicine Doctoral Studies of the University of Granada, Spain.

EEG Data Quality: Determinants and Impact in a Multicenter Study of Children, Adolescents, and Adults with Attention-Deficit/Hyperactivity Disorder (…

2021

Electroencephalography (EEG) represents a widely established method for assessing altered and typically developing brain function. However, systematic studies on EEG data quality, its correlates, and consequences are scarce. To address this research gap, the current study focused on the percentage of artifact-free segments after standard EEG pre-processing as a data quality index. We analyzed participant-related and methodological influences, and validity by replicating landmark EEG effects. Further, effects of data quality on spectral power analyses beyond participant-related characteristics were explored. EEG data from a multicenter ADHD-cohort (age range 6 to 45 years), and a non-ADHD sc…

Maternal risk factors of urinary incontinence during pregnancy and postpartum: A prospective cohort study

2021

Highlights • Urinary incontinence after delivery affects every fifth woman. • Urinary incontinence before pregnancy is a risk factor of postpartum incontinence. • Primiparous women are at a greater risk of urinary incontinence after birth.

Analysis of a database to predict the result of allergy testing in vivo in patients with chronic nasal symptoms.

2014

Background This article uses the logistic regression model for diagnostic decision making in patients with chronic nasal symptoms. We studied the ability of the logistic regression model, obtained by the evaluation of a database, to detect patients with positive allergy skin-prick test (SPT) and patients with negative SPT. The model developed was validated using the data set obtained from another medical institution. Methods The analysis was performed using a database obtained from a questionnaire administered to the patients with nasal symptoms containing personal data, clinical data, and results of allergy testing (SPT). All variables found to be significantly different between patients w…