Search results for "Observational study"

The categorization of amateur cyclists as research participants: findings from an observational study.

2018

Sampling bias is an issue for research involving cyclists. The heterogeneity of cyclist populations, on the basis of skill level and riding purpose, can generate incorrect inferences about one specific segment of the population of interest. In addition, a more accurate categorization would be helpful when physiological parameters are not available. This study proposes using self-reported data to categorize amateur cyclist types by varying skill levels and riding purposes, therefore improving sample selection in experimental studies. A total of 986 cyclists completed an online questionnaire between February and October 2016. Two-step cluster analyses were performed to generate distinct group…

Cancer and central nervous system disorders: protocol for an umbrella review of systematic reviews and updated meta-analyses of observational studies

2017

[Background] The objective of this study will be to synthesize the epidemiological evidence and evaluate the validity of the associations between central nervous system disorders and the risk of developing or dying from cancer.

Risk of mortality among children, adolescents, and adults with autism spectrum disorder or attention deficit hyperactivity disorder and their first-d…

2017

BACKGROUND: Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are childhood onset neurodevelopmental disorders that may persist into adulthood. ASD and ADHD tend to run in families and may have a significant negative impact on the health and longevity of those with the disorder and their relatives. The aim of this study will be to analyze the risk of mortality among children, adolescents, and adults with ASD or ADHD and their first-degree relatives. METHODS/DESIGN: We will conduct a systematic review and meta-analysis of observational studies. Searches of PubMed/MEDLINE, EMBASE, PsycINFO, SCOPUS, and ISI Web of Science will be used to identify epidemiologica…

Current trends in orthodontic journals listed in Journal Citation Reports. A bibliometric study.

2018

Introduction The aim of this study is to analyze articles published in orthodontic journals included in Journal Citation Reports (JCR) to determine current trends in orthodontic publishing. Methods Articles included in orthodontic journals in 2016 JCR and published during 2007-2017 were selected. After applying inclusion criteria, author-based parameters (article title, first author's name, institution and sex, number of authors, number of affiliations, first author's origin, and geographic origin), article-based parameters (article type, main topic, and research design), and the number of cites and self-cites were registered for each article. Results A total of 7119 articles were analyzed,…

2021

An observational cross-sectional survey was planned to analyze the weekly workload reduction of German dentists during lockdown due to the global COVID-19 pandemic. Participants were predominantly members of the Free Association of German Dentists and filled in an online questionnaire. The questionnaire was sent to a total of 9416 dentists, with a response rate of 27.98% (n = 2635). Respondents were divided into seven macro areas by gross domestic product. Nearly two-thirds of dentists (65.16%) reported a reduction in their practice workload of more than 50% compared to the pre-pandemic period with statistically significant differences between German macro areas (p < 0.01). Weekly worklo…

Knowledge about COVID-19 and pandemic impact on Madrid dental students (Spain).

2020

Background: COVID-19 has had a major impact on dental activity, with implications on dental education. The aim of this study was to assess the knowledge about it and the pandemic impact on Spanish dental students. Material and Methods: An observational and cross-sectional study with a 17-items questionnaire was conducted. It was divided into three sections, sociodemographic data, self-perception and knowledge about the COVID-19 protective measures and repercussions on dental students. This survey was carried out in May 2020, and the response rate was 46.16%. The statistical analysis was performed by the Pearson chi-square test and Fisher’s exact test. Results: A total of 235 students respon…

Peripheral Frequency of CD4+ CD28- Cells in Acute Ischemic Stroke: Relationship With Stroke Subtype and Severity Markers.

2015

CD4+ CD28− T cells also called CD28 null cells have been reported as increased in the clinical setting of acute coronary syndrome. Only 2 studies previously analyzed peripheral frequency of CD28 null cells in subjects with acute ischemic stroke but, to our knowledge, peripheral frequency of CD28 null cells in each TOAST subtype of ischemic stroke has never been evaluated. We hypothesized that CD4+ cells and, in particular, the CD28 null cell subset could show a different degree of peripheral percentage in subjects with acute ischemic stroke in relation to clinical subtype and severity of ischemic stroke. The aim of our study was to analyze peripheral frequency of CD28 null cells in subjects…

Risk perception and knowledge of COVID-19 in patients with celiac disease

2021

BACKGROUND We recently demonstrated that the odds of contracting coronavirus disease 2019 (COVID-19) in patients with celiac disease (CeD) is similar to that of the general population. However, how patients with CeD perceive their COVID-19 risk may differ from their actual risk. AIM To investigate risk perceptions of contracting COVID-19 in patients with CeD and determine the factors that may influence their perception. METHODS We distributed a survey throughout 10 countries between March and June 2020 and collected data on demographics, diet, COVID-19 testing, and risk perceptions of COVID-19 in patients with CeD. Participants were recruited through various celiac associations, clinic visi…

Aspirin use and breast cancer risk: a meta-analysis and meta-regression of observational studies from 2001 to 2005

2007

Purpose To examine the recent epidemiological studies on aspirin use and breast cancer risk published from 2001 to 2005 within a meta-analysis, to investigate reasons for heterogeneity between the individual studies and to analyse a dose-response-relationship considering frequency and duration of use. Methods We systematically searched for cohort-studies and case-control-studies from 2001–2005, which evaluated the association between aspirin and breast cancer risk. We calculated a pooled estimate for the relative risk (RR) and investigated reasons for heterogeneity between the individual studies and analysed a dose-response-relationship using random effects mixed models. Results We identifi…

Predictors of scaffold failure and impact of optimized scaffold implantation technique on outcome: Results from the German-Austrian ABSORB RegIstRy.

2021

Aims We aimed to investigate predictors of scaffold failure and the potential impact of an optimized scaffold implantation technique by means of a learning curve on long-term clinical outcome after bioresorbable scaffold (BRS) implantation and to evaluate predictors of scaffold failure. Methods and results A total of 3326 patients were included in this prospective, observational, multi-center study (ClinicalTrials.gov NCT02066623) of consecutive patients undergoing BRS implantation between November 2013 and January 2016. The 3144 patients completed follow-up after 24 months, 3265 patients were eligible for time-to-event-analysis. Clinical endpoints were major adverse cardiac events-a compos…