Search results for " Regression"
showing 10 items of 1835 documents
Non-crossing parametric quantile functions: an application to extreme temperatures
2019
Quantile regression can be used to obtain a non-parametric estimate of a conditional quantile function. The presence of quantile crossing, however, leads to an invalid distribution of the response and makes it difficult to use the fitted model for prediction. In this work, we show that crossing can be alleviated by modelling the quantile function parametrically. We then describe an algorithm for constrained optimisation that can be used to estimate parametric quantile functions with the noncrossing property. We investigate climate change by modelling the long-term trends of extreme temperatures in the Arctic Circle.
Children and Families’ mental health during the first COVID-19 lockdown in Italy
2021
Background: This study aimed to screen a wide range of emotional and behavioural variables emerging during the first COVID-19 pandemic-lockdown in a sample of parents and children, residents in the southern part of Italy, and explore which variables could predict children’s wellbeing. We hypothesised that difficulties in adapting routines to pandemic restrictions, parents’ emotional wellbeing, and attitude towards the pandemic could influence the children’s behavioural attitudes. Methods: 221 parents completed the survey and gave information about 246 children. Ad hoc questionnaires were created and then exploratory reduced in factors. Strengths and Difficulties Questionnaire (SDQ) for pare…
Primary multifocal anaplastic large cell lymphoma with eyelid involvement: a case report
2019
ABSTRACT Ocular adnexal involvement in CD30+ lymphoproliferative disorders is rare. We report the case of a 73-year-old woman with a relapsing primary cutaneous anaplastic large cell lymphoma on her eyelid. A systemic extension study excluded extracutaneous involvement. Systemic chemotherapy resulted in an optimal response, with complete regression of the cutaneous lesions. There has been no recurrence during the 2 years of follow-up. RESUMO O acometimento ocular adicional nos distúrbios linfoproliferativos CD30+ é raro. Relatamos o caso de uma mulher de 73 anos com linfoma de grandes células anaplásicas primárias recidivantes em sua pálpebra. A avaliação sistêmica excluiu envolvimento extr…
Subjective symptoms related to GSM radiation from mobile phone base stations : a cross-sectional study
2013
Objectives: We performed a reanalysis of the data from Navarro et al., 2003, in which health symptoms related to microwave exposure from mobile phone base stations (BS) were explored, including data obtained in a retrospective inquiry about fear of exposure from BS. Design: Cross-sectional study. Setting: La Ñora (Murcia), Spain. Participants: Participants with known illness in 2003 were subsequently disregarded: 88 participants instead of 101 (in 2003) were analysed. Since weather circumstances can influence exposure, we restricted data to measurements made under similar weather conditions. Outcomes and methods: A statistical method indifferent to the assumption of normality was employed: …
Study of the immunophenotype of the inflammatory cells in melanomas with regression and halo nevi.
2015
Abstract The pathogenesis and prognostic implications of regression in melanoma are not well understood. It has traditionally been considered an immunologically mediated phenomenon. Improvement in the knowledge of the mechanisms that lead to regression may prove to be of great value in an era in which treatments oriented to the augmentation of the host's immunity against melanoma have demonstrated excellent clinical results. This study was designed to improve the understanding of the mechanisms underlying melanoma regression and the differences between similar situations in benign melanocytic nevus. The study sample consisted of 77 lesions: 62 melanomas and 15 halo nevi. The following marke…
Determinants of self-reported smoking and misclassification during pregnancy, and analysis of optimal cut-off points for urinary cotinine: a cross-se…
2013
10 p. Objectives: To estimate the prevalence and factors associated with smoking and misclassification in pregnant women from INMA (INfancia y Medio Ambiente, Environment and Childhood) project, Spain, and to assess the optimal cut-offs for urinary cotinine (UC) that best distinguish daily and occasional smokers with varying levels of second-hand smoke (SHS) exposure.-- Design: We used logistic regression models to study the relationship between sociodemographic variables and self-reported smoking and misclassification (self-reported non-smokers with UC >50 ng/ml). Receiver operating characteristic (ROC) curves were used to calculate the optimal cut-off point for discriminating smokers. The…
Pregnancy e-health: a multicenter Italian cross-sectional study on internet use and decision-making among pregnant women
2013
Background Our study aimed to estimate the prevalence of pregnancy e-health seekers in a large Italian sample; to explore the factors influencing the choices of the childbearing women regarding their lifestyles after internet consultation; and finally to investigate potential differences between primiparous and multiparous women in internet use to find information about pregnancy. Methods A multicentre survey was carried out in seven Italian cities. Data were collected through a validated questionnaire administered in waiting rooms of outpatient departments by medical doctors. Respondents were questioned about their sociodemographic status, their use of the internet to seek pregnancy inform…
The association between respiratory tract infection incidence and localised meningitis epidemics: an analysis of high-resolution surveillance data fr…
2017
AbstractMeningococcal meningitis epidemics in the African meningitis belt consist of localised meningitis epidemics (LME) that reach attack proportions of 1% within a few weeks. A meningococcal serogroup A conjugate vaccine was introduced in meningitis belt countries from 2010 on, but LME due to other serogroups continue to occur. The mechanisms underlying LME are poorly understood, but an association with respiratory pathogens has been hypothesised. We analysed national routine surveillance data in high spatial resolution (health centre level) from 13 districts in Burkina Faso, 2004–2014. We defined LME as a weekly incidence rate of suspected meningitis ≥75 per 100,000 during ≥2 weeks; and…
[Geographic variation in the prevalence of asthma symptoms in Spanish children and adolescents. International Study of Asthma and Allergies in Childh…
2005
Objective TO analyze geographic variations in the prevalence of symptoms related to asthma in Spanish children and adolescents. Population and methods In 2001 and 2002, the Spanish arm of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase 3 collected information on 28 445 children in the age bracket of 6-7 years in 10 metropolitan areas (A Coruna, Asturias, Barcelona, Bilbao, Cartagena, Castellon, Madrid, Pamplona, San Sebastian, and Valencia) and on 31 257 adolescents in the bracket 13-14 years in 11 areas (the previously named areas plus Valladolid). An asthma symptom questionnaire was filled in by parents or the adolescents themselves. Differences in symptoms betw…
Pre and postnatal exposure to mercury and respiratory health in preschool children from the Spanish INMA Birth Cohort Study
2021
Effects of mercury on maturing immune system have been reported, however the association with respiratory and allergy problems during infancy remains unclear. The aim of this study is to evaluate the association between pre and postnatal mercury exposure and respiratory and allergy problems among preschool children and to examine the role of potential modifying factors. Study subjects were children participant in Spanish Childhood and Environment Project (INMA, 2003-2008). We measured total mercury levels in cord blood (n = 1868) and hair at 4 years of age (n = 1347). Respiratory outcomes (wheezing, severe wheezing, chestiness, persistent cough, eczema and otitis) were obtained by questionn…