robust variance
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2022 ◽  
Vol 13 ◽  
pp. 215013192110626
Author(s):  
David D. McFadden ◽  
Shari L. Bornstein ◽  
Robert Vassallo ◽  
Bradley R. Salonen ◽  
Mohammed Nadir Bhuiyan ◽  
...  

Objectives: The purpose of the present study was to assess and describe the severity of symptoms reported by Covid-19 positive patients who vaped (smoked e-cigarettes) when compared to those who did not vape or smoke at the time of the diagnosis of Covid-19. Methods: Patients from this study are from a well-characterized patient cohort collected at Mayo Clinic between March 1, 2020 and February 28, 2021; with confirmed COVID-19 diagnosis defined as a positive result on reverse-transcriptase–polymerase-chain-reaction (RT-PCR) assays from nasopharyngeal swab specimens. Among the 1734 eligible patients, 289 patients reported current vaping. The cohort of vapers (N = 289) was age and gender matched to 1445 covid-19 positive patients who did not vape. The data analyzed included: date of birth, gender, ethnicity, race, marital status, as well as lifestyle history such as vaping and smoking and reported covid-19 symptoms experienced. Results: A logistic regression analysis was performed separately for each symptom using generalized estimating equations (GEE) with robust variance estimates in order to account for the 1:5 age, sex, and race matched set study design. Patients who vaped and developed Covid-19 infection were more likely to have chest pain or tightness (16% vs 10%, vapers vs non vapers, P = .005), chills (25% vs 19%, vapers vs non vapers, P = .0016), myalgia (39% vs 32%, vapers vs non vapers, P = .004), headaches (49% vs 41% vapers vs non vapers, P = .026), anosmia/dysgeusia (37% vs 30%, vapers vs non vapers, P = .009), nausea/vomiting/abdominal pain (16% vs 10%, vapers vs non vapers, P = .003), diarrhea (16% vs 10%, vapers vs non vapers, P = .004), and non-severe light-headedness (16% vs 9%, vapers vs non vapers, P < .001). Conclusion: Vapers experience higher frequency of covid-19 related symptoms when compared with age and gender matched non-vapers. Further work should examine the impact vaping has on post-covid symptom experience.


2021 ◽  
pp. 003465432110608
Author(s):  
Virginia Clinton-Lisell

In this study, a meta-analysis of reading and listening comprehension comparisons across age groups was conducted. Based on robust variance estimation (46 studies; N = 4,687), the overall difference between reading and listening comprehension was not reliably different (g = 0.07, p = .23). Reading was beneficial over listening when the reading condition was self-paced (g = 0.13, p = .049) rather than experimenter-paced (g = −0.32, p = .16). Reading also had a benefit when inferential and general comprehension rather than literal comprehension was assessed (g = 0.36, p = .02; g = .15, p = .05; g = −0.01, p = .93, respectively). There was some indication that reading and listening were more similar in languages with transparent orthographies than opaque orthographies (g = 0.001, p = .99; g = 0.10, p = .19, respectively). The findings may be used to inform theories of comprehension about modality influences in that both lower-level skill and affordances vary comparisons of reading and listening comprehension. Moreover, the findings may guide choices of modality; however, both audio and written options are needed for accessible instruction.


2021 ◽  
Vol 14 (1) ◽  
pp. 235
Author(s):  
Álvaro Francisco Lopes de Sousa ◽  
Guilherme Schneider ◽  
Herica Emilia Félix de Carvalho ◽  
Layze Braz de Oliveira ◽  
Shirley Verônica Melo Almeida Lima ◽  
...  

In the wake of the COVID-19 pandemic, a complex phenomenon called the “infodemic” has emerged, compromising coping with the pandemic. This study aims to estimate the prevalence of agreement with misinformation about COVID-19 and to identify associated factors. A web survey was carried out in Portuguese-speaking countries in two stages: 1. the identification of misinformation circulating in the included countries; 2. a multicentric online survey with residents of the included countries. The outcome of the study was agreement or disagreement with misinformation about COVID-19. Multivariate analyzes were conducted using the Poisson regression model with robust variance, a logarithmic link function, and 95% confidence intervals. The prevalence of agreement with misinformation about COVID-19 was 63.9%. The following factors increased the prevalence of this outcome: having a religious affiliation (aPR: 1454, 95% CI: 1393–1517), having restrictions on leisure (aPR: 1230, 95% CI: 1127–1342), practicing social isolation (aPR: 1073, 95% CI: 1030–1118), not avoiding agglomeration (aPR: 1060, 95% CI: 1005–1117), not seeking/receiving news from scientific sources (aPR: 1153, 95% CI: 1068–1245), seeking/receiving news from three or more non-scientific sources (aPR: 1114, 95% CI: 1049–1182), and giving credibility to news carried by people from social networks (aPR: 1175, 95% CI: 1104–1251). There was a high prevalence of agreement with misinformation about COVID-19. The quality, similarity, uniformity, and acceptance of the contents indicate a concentration of themes that reflect “homemade”, simple, and easy methods to avoid infection by SARS-CoV-2, compromising decision-making and ability to cope with the disease.


Author(s):  
Walter L Arias Gallegos ◽  
Renzo Rivera

Background: The sexual behavior of women is associated with various protective or risk factors, which are important to assess. To determine the socioeconomic factors associated with the sexual behavior of Peruvian women within 15 and 25 years old. Method: A secondary analysis of the 2016 Demographic and Family Health Survey (ENDES) was conducted. Our sample was 7962 women from 15 to 25 years old, from all over the Peruvian territory. Associative analyzes were carried out on the age of sexual initiation, the number of sexual partners and the use of contraceptives, based on sociodemographic variables. Poisson regression with robust variance was also used. Results: It was found the factors, that are associated with the age of sexual initiation and the number of sexual partners, are the area of origin, marital status, educational level, employment status and socioeconomic level. While women who work and whose partners do not drink alcohol are the most likely to use contraceptives. Conclusions: It can be concluded that certain socioeconomic and work conditions act as protective factors of female sexual behavior, while having a partner who drinks alcohol is a risk factor.


2021 ◽  
Author(s):  
Osman U. Ekiz ◽  

In multiple linear regression analysis, the variance inflation factor is a well-known collinearity measure. It is defined as the function of the coefficient of determination between the explanatory variables, and it is based on the maximum likelihood estimator of the regression coefficients. Nevertheless, in addition to outliers, leverage observations can have significant impact on the coefficient of determination, and thereby the variance inflation factor. This study presents an improved robust variance inflation factor estimator that is not affected by these observations. Simulation studies and a real data analysis indicate that the modified robust variance inflation factor estimator performs better than the traditional one.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alexandra Doncarli ◽  
Lucia Araujo-Chaveron ◽  
Catherine Crenn-Hebert ◽  
Virginie Demiguel ◽  
Julie Boudet-Berquier ◽  
...  

Abstract Background In the context of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, consultations and pregnancy monitoring examinations had to be reorganised urgently. In addition, women themselves may have postponed or cancelled their medical monitoring for organisational reasons, for fear of contracting the disease caused by SARS-CoV-2 (COVID-19) or for other reasons of their own. Delayed care can have deleterious consequences for both the mother and the child. Our objective was therefore to study the impact of the SARS-CoV-2 pandemic and the first lockdown in France on voluntary changes by pregnant women in the medical monitoring of their pregnancy and the associated factors. Methods A cross-sectional study was conducted in July 2020 using a web-questionnaire completed by 500 adult (> 18 years old) pregnant women during the first French lockdown (March–May 2020). A robust variance Poisson regression model was used to estimate adjusted prevalence ratios (aPRs). Results Almost one women of five (23.4%) reported having voluntarily postponed or foregone at least one consultation or pregnancy check-up during the lockdown. Women who were professionally inactive (aPR = 1.98, CI95%[1.24–3.16]), who had experienced serious disputes or violence during the lockdown (1.47, [1.00–2.16]), who felt they received little or no support (1.71, [1.07–2.71]), and those who changed health professionals during the lockdown (1.57, [1.04–2.36]) were all more likely to have voluntarily changed their pregnancy monitoring. Higher level of worry about the pandemic was associated with a lower probability of voluntarily changing pregnancy monitoring (0.66, [0.46–0.96]). Conclusions Our results can guide prevention and support policies for pregnant women in the current and future pandemics.


2021 ◽  
pp. 108705472110588
Author(s):  
Pedro San Martin Soares ◽  
Paula Duarte de Oliveira ◽  
Fernando César Wehrmeister ◽  
Ana Maria Baptista Menezes ◽  
Luis Augusto Rohde ◽  
...  

Objective This study examined the association between WM and ADHD symptoms in young adults and whether IQ-score influenced this association. Method Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed ( N = 2,845). Working memory and ADHD symptoms were collected at 22 years. IQ was examined at age 18. Poisson regression with robust variance was used to assess the associations between working memory and ADHD symptoms. We also evaluated whether IQ modified associations between working memory and ADHD symptoms. Results Working memory was negatively associated with Inattention symptoms of ADHD. The association between working memory and hyperactivity-impulsivity symptoms of ADHD varied by IQ. Conclusions This study provides new insights to theories about the relationship between WM and ADHD symptoms as well as the development of interventions aimed at improving the performance of WM in ADHD.


2021 ◽  
Author(s):  
Mélanie Drolet ◽  
Aurélie Godbout ◽  
Myrto Mondor ◽  
Guillaume Béraud ◽  
Léa Drolet-Roy ◽  
...  

ABSTRACTBackgroundSince the beginning of the Covid-19 pandemic, many countries, including Canada, have adopted unprecedented physical distancing measures such as closure of schools and non-essential businesses, and restrictions on gatherings and household visits. We described time trends in social contacts for the pre-pandemic and pandemic periods in Quebec, Canada.MethodsCONNECT is a population-based study of social contacts conducted shortly before (2018/2019) and during the Covid-19 pandemic (April 2020 – February 2021), using the same methodology for both periods. We recruited participants by random-digit-dialing and collected data by self-administered web-based questionnaires. Questionnaires documented socio-demographic characteristics and social contacts for two assigned days. A contact was defined as a two-way conversation at a distance ≤2 meters or as a physical contact, irrespective of masking. We used weighted generalized linear models with a Poisson distribution and robust variance (taking possible overdispersion into account) to compare the mean number of social contacts over time by characteristics.ResultsA total of 1291 and 5516 Quebecers completed the study before and during the pandemic, respectively. Contacts significantly decreased from a mean of 8 contacts/day prior to the pandemic to 3 contacts/day during the spring 2020 lockdown. Contacts remained lower than the pre-Covid period thereafter (lowest=3 contacts/day during the Christmas 2020/2021 holidays, highest=5 in September 2020). Contacts at work, during leisure activities/other locations, and at home with visitors showed the greatest decreases since the beginning of the pandemic. All sociodemographic subgroups showed significant decreases of contacts since the beginning of the pandemic.ConclusionPhysical distancing measures in Quebec significantly decreased social contacts, which most likely mitigated the spread of Covid-19.


2021 ◽  
Vol 26 (suppl 3) ◽  
pp. 5281-5292
Author(s):  
Anna Martha Vaitses Fontanari ◽  
Siobhan Churchill ◽  
Maiko Abel Schneider ◽  
Bianca Soll ◽  
Angelo Brandelli Costa ◽  
...  

Abstract Transgender and gender non-binary youth are particularly vulnerable to tobacco smoking and susceptible to smoking adverse health outcomes. That is, they are in special risk to start smoking and, after starting, they may face worse outcomes when comparing to their cisgender peers. Therefore, the present study aims to evaluate factors associated with tobacco use among transgender and gender non-binary youth. Brazilian youth aged 16 to 25 who identify as transgender or gender non-binary answered an online questionnaire. Poisson regression with robust variance was run to predict smoking cigarettes based on individual and environmental factors. 14.1% of 206 youth reported smoking cigarettes daily, whereas 9.3% of participants reported smoking e-cigarettes occasionally. Drug use, lack of social support, deprivation, discrimination, the wait for medical gender-affirming procedures and being outside school were associated with smoking cigarettes. Contextual and individual factors should be further explored in causal analysis and taken into consideration when planning smoking prevention and cessation interventions for transgender and gender non-binary youth.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256441
Author(s):  
Dong Van Hoang ◽  
Shohei Yamamoto ◽  
Takako Miki ◽  
Ami Fukunaga ◽  
Zobida Islam ◽  
...  

ABO blood types could be a biological predisposition for depression. The present cross-sectional analysis was conducted amid the second wave of COVID-19 in Japan during July 2020. We wanted to investigate the association between ABO blood types and depressive symptoms among workers (352 men and 864 women, aged 21–73 years) of a medical institution in Tokyo, Japan, which took a leading role in the response to COVID-19 in the country. A Poisson regression model with a robust variance estimator was used to estimate the prevalence ratio (PR) and 95% confidence interval (CI) for depressive symptoms associated with ABO blood types. Overall, the prevalence of depressive symptoms (using two questions employed from a Two-question case-finding instrument) was 22.0%. The adjusted PRs (95% CI) for depressive symptoms, comparing the carriers of blood type O, A, and AB with those of type B, were 0.88 (0.66, 1.18), 0.81 (0.62, 1.07), and 1.07 (0.74, 1.53), respectively. There was no difference in the prevalence of depressive symptoms between non-B and B carriers. The present study did not support the association of ABO blood types with depressive symptoms.


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