scholarly journals Bayesian hierarchical piecewise regression models: a tool to detect trajectory divergence between groups in long-term observational studies

2017 ◽  
Vol 17 (1) ◽  
Author(s):  
Marie-jeanne Buscot ◽  
Simon S. Wotherspoon ◽  
Costan G. Magnussen ◽  
Markus Juonala ◽  
Matthew A. Sabin ◽  
...  
Keyword(s):  
Observational Studies ◽  
Regression Models ◽  
Bayesian Hierarchical ◽  
Piecewise Regression ◽  
Trajectory Divergence

scholarly journals COVID-19 Preventive Behaviours in Cameroon: A Six-Month Online National Survey

2021 ◽  
Vol 18 (5) ◽  
pp. 2554
Author(s):  
Joseph Nelson Siewe Fodjo ◽  
Leonard Ngarka ◽  
Wepnyu Y. Njamnshi ◽  
Leonard N. Nfor ◽  
Michel K. Mengnjo ◽  
...  
Keyword(s):  
Regression Models ◽  
Health Personnel ◽  
Online Survey ◽  
Preventive Measures ◽  
Face Mask ◽  
Logistic Regression Models ◽  
Adherence Score ◽  
Preventive Behaviour ◽  
Predictors Of Adherence

Since March 2020, the Cameroonian government implemented nationwide measures to stall COVID-19 transmission. However, little is known about how well these unprecedented measures are being observed as the pandemic evolves. We conducted a six-month online survey to assess the preventive behaviour of Cameroonian adults during the COVID-19 outbreak. A five-point adherence score was constructed based on self-reported observance of the following preventive measures: physical distancing, face mask use, hand hygiene, not touching one’s face, and covering the mouth when coughing or sneezing. Predictors of adherence were investigated using ordinal logistic regression models. Of the 7381 responses received from all ten regions, 73.3% were from male respondents and overall mean age was 32.8 ± 10.8 years. Overall mean adherence score was 3.96 ± 1.11 on a scale of 0–5. Mean weekly adherence scores were initially high, but gradually decreased over time accompanied by increasing incidence of COVID-19 during the last study weeks. Predictors for higher adherence included higher age, receiving COVID-19 information from health personnel, and agreeing with the necessity of lockdown measures. Meanwhile, experiencing flu-like symptoms was associated with poor adherence. Continuous observance of preventive measures should be encouraged among Cameroonians in the medium- to long-term to avoid a resurgence in COVID-19 infections.

Long-Term Exposure to PM2.5 and Cognitive Decline: A Longitudinal Population-Based Study

2021 ◽  
pp. 1-9
Author(s):  
Giulia Grande ◽  
Jing Wu ◽  
Petter L.S. Ljungman ◽  
Massimo Stafoggia ◽  
Tom Bellander ◽  
...  
Keyword(s):  
Air Pollution ◽  
Cognitive Decline ◽  
Population Based ◽  
Cerebrovascular Diseases ◽  
Air Pollutant ◽  
National Study ◽  
Piecewise Regression ◽  
Risk Increase ◽  
Restricted Cubic Splines

Background: A growing but contrasting evidence relates air pollution to cognitive decline. The role of cerebrovascular diseases in amplifying this risk is unclear. Objectives: 1) Investigate the association between long-term exposure to air pollution and cognitive decline; 2) Test whether cerebrovascular diseases amplify this association. Methods: We examined 2,253 participants of the Swedish National study on Aging and Care in Kungsholmen (SNAC-K). One major air pollutant (particulate matter ≤2.5μm, PM2.5) was assessed yearly from 1990, using dispersion models for outdoor levels at residential addresses. The speed of cognitive decline (Mini-Mental State Examination, MMSE) was estimated as the rate of MMSE decline (linear mixed models) and further dichotomized into the upper (25%fastest cognitive decline), versus the three lower quartiles. The cognitive scores were used to calculate the odds of fast cognitive decline per levels of PM2.5 using regression models and considering linear and restricted cubic splines of 10 years exposure before the baseline. The potential modifier effect of cerebrovascular diseases was tested by adding an interaction term in the model. Results: We observed an inverted U-shape relationship between PM2.5 and cognitive decline. The multi-adjusted piecewise regression model showed an increased OR of fast cognitive decline of 81%(95%CI = 1.2–3.2) per interquartile range difference up to mean PM2.5 level (8.6μg/m3) for individuals older than 80. Above such level we observed no further risk increase (OR = 0.89;95%CI = 0.74–1.06). The presence of cerebrovascular diseases further increased such risk by 6%. Conclusion: Low to mean PM2.5 levels were associated with higher risk of accelerated cognitive decline. Cerebrovascular diseases further amplified such risk.

scholarly journals Reproductive Performance Following Hysteroscopic Surgery for Uterine Septum: Results from a Single Surgeon Data

2021 ◽  
Vol 10 (1) ◽  
pp. 130
Author(s):  
Ertan Saridogan ◽  
Mona Salman ◽  
Lerzan Sinem Direk ◽  
Ali Alchami
Keyword(s):  
Reproductive Performance ◽  
Observational Studies ◽  
Patient Characteristics ◽  
Reproductive Outcomes ◽  
Hysteroscopic Surgery ◽  
High Quality Evidence ◽  
Study Results ◽  
Significant Difference ◽  
Uterine Septum

Uterine septum can negatively affect reproductive outcomes in women. Based on evidence from retrospective observational studies, hysteroscopic incision has been considered a solution to improve reproductive performance, however there has been recent controversy on the need for surgery for uterine septum. High quality evidence from prospective studies is still lacking, and until it is available, experts are encouraged to publish their data. We are therefore presenting our data that involves analysis of the patient characteristics, surgical approach and long-term reproductive outcomes of women who received treatment for uterine septum under the care of a single surgeon. This includes all women (99) who underwent hysteroscopic surgery for uterine septum between January 2001 and December 2019. Of those 99 women treated for intrauterine septum who were trying to conceive, 91.4% (64/70) achieved pregnancy, 78.6% (55/70) had live births and 8.6% (6/70) had miscarriages. No statistically significant difference was found in the live birth rates when data was analyzed in subgroups based on age, reason for referral/aetiology and severity of pathology. Our study results support the view that surgical treatment of uterine septa is beneficial in improving reproductive outcomes.

scholarly journals Long-term exposure to iron and copper in fine particulate air pollution and their combined impact on reactive oxygen species concentration in lung fluid: a population-based cohort study of cardiovascular disease incidence and mortality in Toronto, Canada

2020 ◽  
Author(s):  
Zilong Zhang ◽  
Scott Weichenthal ◽  
Jeffrey C Kwong ◽  
Richard T Burnett ◽  
Marianne Hatzopoulou ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Cardiovascular Disease ◽  
Regression Models ◽  
Population Based ◽  
Sensitivity Analyses ◽  
Oxygen Species ◽  
Lung Fluid ◽  
Fine Particulate ◽  
Combined Impact

Abstract Background Exposure to fine particulate (PM2.5) air pollution is associated with increased cardiovascular disease (CVD), but less is known about its specific components, such as metals originating from non-tailpipe emissions. We investigated the associations of long-term exposure to metal components [iron (Fe) and copper (Cu)] in PM2.5 with CVD incidence. Methods We conducted a population-based cohort study in Toronto, Canada. Exposures to Fe and Cu in PM2.5 and their combined impact on the concentration of reactive oxygen species (ROS) in lung fluid were estimated using land use regression models. Incidence of acute myocardial infarction (AMI), congestive heart failure (CHF) and CVD death was ascertained using health administrative datasets. We used mixed-effects Cox regression models to examine the associations between the exposures and health outcomes. A series of sensitivity analyses were conducted, including indirect adjustment for individual-level cardiovascular risk factors (e.g. smoking), and adjustment for PM2.5 and nitrogen dioxide (NO2). Results In single-pollutant models, we found positive associations between the three exposures and all three outcomes, with the strongest associations detected for the estimated ROS. The associations of AMI and CHF were sensitive to indirect adjustment, but remained robust for CVD death in all sensitivity analyses. In multi-pollutant models, the associations of the three exposures generally remained unaltered. Interestingly, adjustment for ROS did not substantially change the associations between PM2.5 and CVD, but attenuated the associations of NO2. Conclusions Long-term exposure to Fe and Cu in PM2.5 and their combined impact on ROS were consistently associated with increased CVD death.

scholarly journals Early High-dose Caffeine Improves Respiratory Outcomes in Preterm Infants

Children ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 501
Author(s):  
Vineet Lamba ◽  
Oscar Winners ◽  
Prem Fort
Keyword(s):  
Mechanical Ventilation ◽  
Preterm Infants ◽  
Regression Models ◽  
High Dose ◽  
Long Term Outcomes ◽  
Logistic Regression Models ◽  
Caffeine Citrate ◽  
Timing Of Initiation ◽  
Respiratory Outcomes

The objective of the study is to determine if early high-dose caffeine (HD) therapy is associated with shorter duration of mechanical ventilation, bronchopulmonary dysplasia (BPD), or decreased need for mechanical ventilation. We conducted a single center, retrospective cohort study of 273 infants less than 32 weeks gestational age (GA). Infants receiving early HD (10 mg/kg/day maintenance) caffeine citrate started within 24 h of life were compared with those receiving LD (6 mg/kg/day) with variable timing of initiation using linear and logistic regression models. The infants in the early HD group had 91.4 (95% confidence interval (CI): −166.6, −16.1; p = 0.018) less hours of mechanical ventilation up to 36 weeks PMA or discharge as compared with the LD group. Moreover, infants in the HD group had 0.37 (95% CI: 0.14, 0.97; p = 0.042) times lower odds of developing moderate/severe BPD compared with the LD group. Infants receiving early HD caffeine had improved respiratory outcomes with no increase in measured comorbidities. Large prospective studies are needed to determine the long-term outcomes of using high-dose caffeine prophylaxis for preterm infants.

Discovery of polynomial equations for regression

2004 ◽  
Vol 1 (1) ◽  
pp. 131-142
Author(s):  
Ljupčo Todorovski ◽  
Sašo Džeroski ◽  
Peter Ljubič
Keyword(s):  
Efficient Method ◽  
Regression Models ◽  
Predictive Accuracy ◽  
State Of The Art ◽  
Numerical Data ◽  
Predictive Performance ◽  
Polynomial Equations ◽  
Regression Methods ◽  
Piecewise Regression ◽  
Standard Regression

Both equation discovery and regression methods aim at inducing models of numerical data. While the equation discovery methods are usually evaluated in terms of comprehensibility of the induced model, the emphasis of the regression methods evaluation is on their predictive accuracy. In this paper, we present Ciper, an efficient method for discovery of polynomial equations and empirically evaluate its predictive performance on standard regression tasks. The evaluation shows that polynomials compare favorably to linear and piecewise regression models, induced by the existing state-of-the-art regression methods, in terms of degree of fit and complexity.

Lifestyle intervention strategies in early life to improve pregnancy outcomes and long-term health of offspring: a narrative review

2018 ◽  
Vol 10 (3) ◽  
pp. 314-321 ◽  
Author(s):  
Romy Gaillard ◽  
John Wright ◽  
Vincent W.V. Jaddoe
Keyword(s):  
Health Outcomes ◽  
Pregnancy Outcomes ◽  
Early Life ◽  
Observational Studies ◽  
Postnatal Period ◽  
Modifiable Risk Factors ◽  
Lifestyle Interventions ◽  
Randomized Controlled ◽  
Offspring Health

AbstractAdverse exposures during fetal life and the postnatal period influence physical, cognitive and emotional development, and predispose to an increased risk of various chronic diseases throughout the life course. Findings from large observational studies in various populations and experimental animal studies have identified different modifiable risk factors in early life. Adverse maternal lifestyle factors, including overweight, unhealthy diet, sedentary behavior, smoking, alcohol consumption and stress in the preconception period and during pregnancy, are the most common modifiable risk factors leading to a suboptimal in-utero environment for fetal development. In the postnatal period, breastfeeding, infant growth and infant dietary intake are important modifiable factors influencing long-term offspring health outcomes. Despite the large amount of findings from observational studies, translation to lifestyle interventions seems to be challenging. Currently, randomized controlled trials focused on the influence of lifestyle interventions in these critical periods on short-term and long-term maternal and offspring health outcomes are scarce, have major limitations and do not show strong effects on maternal and offspring outcomes. New and innovative approaches are needed to move from describing these causes of ill-health to start tackling them using intervention approaches. Future randomized controlled lifestyle intervention studies and innovative observational studies, using quasi-experimental designs, are needed focused on the effects of an integrated lifestyle advice from preconception onwards on pregnancy outcomes and long-term health outcomes in offspring on a population level.

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