scholarly journals Quest for Optimal Regression Models in SARS-CoV-2 Wastewater Based Epidemiology

Author(s):  
Parisa Aberi ◽  
Rezgar Arabzadeh ◽  
Heribert Insam ◽  
Rudolf Markt ◽  
Markus Mayr ◽  
...  

Wastewater-based epidemiology is a recognised source of information for pandemic management. In this study, we investigated the correlation between a SARS-CoV-2 signal derived from wastewater sampling and COVID-19 incidence values monitored by means of individual testing programs. The dataset used in the study is composed of timelines (duration approx. five months) of both signals at four wastewater treatment plants across Austria, two of which drain large communities and the other two drain smaller communities. Eight regression models were investigated to predict the viral incidence under varying data inputs and pre-processing methods. It was found that population-based normalisation and smoothing as a pre-processing of the viral load data significantly influence the fitness of the regression models. Moreover, the time latency lag between the wastewater data and the incidence derived from the testing program was found to vary between 2 and 7 days depending on the time period and site. It was found to be necessary to take such a time lag into account by means of multivariate modelling to boost the performance of the regression. Comparing the models, no outstanding one could be identified as all investigated models are revealing a sufficient correlation for the task. The pre-processing of data and a multivariate model formulation is more important than the model structure.

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1639
Author(s):  
Zhongyao Li ◽  
Dongqing Wang ◽  
Edward A. Ruiz-Narváez ◽  
Karen E. Peterson ◽  
Hannia Campos ◽  
...  

Only a few studies primarily examined the associations between starchy vegetables (other than potatoes) and metabolic syndrome (MetS). We aimed to evaluate the association between starchy vegetables consumption and MetS in a population-based sample of Costa Rican adults. We hypothesized that a higher overall intake of starchy vegetables would not be associated with higher MetS prevalence. In this cross-sectional study, log-binomial regression models were used to estimate prevalence ratios (PRs) of MetS across quintiles of total, unhealthy, healthy starchy vegetables, and individual starchy vegetables (potatoes, purple sweet potatoes, etc.), among 1881 Costa Rican adults. Least square means and 95% confidence intervals (CIs) from linear regression models were estimated for each MetS component by categories of starchy vegetable variables. Higher intakes of starchy vegetables were associated with a higher prevalence of MetS in crude models, but no significant trends were observed after adjusting for confounders. A significant inverse association was observed between total starchy and healthy starchy vegetables consumption and fasting blood glucose. In this population, starchy vegetables might be part of a healthy dietary pattern.


Author(s):  
Zilong Zhang ◽  
Scott Weichenthal ◽  
Jeffrey C Kwong ◽  
Richard T Burnett ◽  
Marianne Hatzopoulou ◽  
...  

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.


Author(s):  
L Hernandez Ronquillo ◽  
L Thorpe ◽  
P Pahwa ◽  
J Tellez Zenteno

Background: There is no available estimate of the incidence and mortality of epilepsy in all age groups in the Canadian population. This study aimed to measure the incidence, prevalence, mortality and the secular trends for epilepsy in Saskatchewan between 2005 and 2010. Methods: A population-based cohort study was established from Saskatchewan’s provincial health administrative data. The population was followed until termination of coverage, death, or 31 December 2010. Individuals with epilepsy were identified based on ICD codes algorithms from 2005 to 2010. Results: The age-standardized incidence of epilepsy was 62 per 100,000 person-year. The age-standardized incidence rate of epilepsy in self-declared Registered Indians was 122 per 100,000 person-year. There was a significant decrease in the incidence of epilepsy for all groups over the study period. The age-standardized prevalence of epilepsy was 9 per 1,000 people. There was a significant increase in the prevalence of epilepsy over this time period. The adjusted mortality rate was 0.023 per 1000 person-year, and the all-cause Standardized Mortality Ration for epilepsy was 2.45. The SMR remained constant over the six-year period of the study. Conclusions: This study is the first in Canada to measure the incidence and all-cause mortality of epilepsy in all age groups.


2021 ◽  
Author(s):  
Nada Krivonakova ◽  
Andrea Soltysova ◽  
Michal Tamas ◽  
Zdenko Takac ◽  
Ján Krahulec ◽  
...  

Abstract COVID-19 pandemic caused by β-coronavirus SARS-CoV-2 emerges to intensive scientific research and monitoring of wastewaters because of their possible important role in identifying and early warning of a spread of the virus in the community. In our study, we investigated the prevalence of the COVID-19 disease in the population of the capital city of Slovakia, Bratislava, based on wastewater monitoring from September 2020 until March 2021. Samples were analyzed from two major wastewater treatment plants of the city with reaching nearly 0.6 million monitored inhabitants. Obtained results from the wastewater analysis suggest significant statistical dependence. High correlations between the number of viral particles in wastewater and the number of reported positive nasopharyngeal RT-qPCR tests of infected individuals with a time lag of 2 weeks / 12 days (R2 = 83.78% / R2 = 52.65%) as well as with a reported number of death cases with a time lag of 4 weeks / 27 days (R2 = 83.21% / R2 = 61.89%) was observed. The obtained results and subsequent mathematical modeling will serve in the future as an early warning system for the occurrence of a local site of infection and, at the same time, predict the load on the health system up to two weeks in advance.


2017 ◽  
Author(s):  
A Tsui ◽  
D Kuh ◽  
M Richards ◽  
D Davis

AbstractINTRODUCTIONFew population studies have investigated whether longitudinal decline after delirium in mid-to-late life might affect specific cognitive domains.METHODSParticipants from a birth cohort completing assessments of search speed, verbal memory and the Addenbrooke’s Cognitive Examination at age 69 were asked about delirium symptoms between ages 60-69. Linear regression models estimated associations between delirium symptoms and cognitive outcomes.RESULTSPeriod prevalence of delirium between 60 and 69 was 4% (95% CI 3.2%,4.9%). Self-reported symptoms of delirium over the seventh decade were associated with worse scores in the Addenbrooke’s Cognitive Examination (−1.7 points, 95% CI −3.2, −0.1, p=0.04). In association with delirium symptoms, verbal memory scores were initially lower, with subsequent decline in search speed by age 69. These effects were independent of other Alzheimer’s risk factors.DISCUSSIONDelirium symptoms may be common even at relatively younger ages, and their presence may herald cognitive decline, particularly in search speed, over this time period.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Nathan Maassel ◽  
Abbie Saccary ◽  
Daniel Solomon ◽  
David Stitelman ◽  
Yunshan Xu ◽  
...  

Abstract Background Despite a national decrease in emergency department visits in the United States during the first 10 months of the pandemic, preliminary Consumer Product Safety Commission data indicate increased firework-related injuries. We hypothesized an increase in firework-related injuries during 2020 compared to years prior related to a corresponding increase in consumer firework sales. Methods The National Electronic Injury Surveillance System (NEISS) was queried from 2018 to 2020 for cases with product codes 1313 (firework injury) and narratives containing “fireworks”. Population-based national estimates were calculated using US Census data, then compared across the three years of study inclusion. Patient demographic and available injury information was also tracked and compared across the three years. Firework sales data obtained from the American Pyrotechnics Association were determined for the same time period to examine trends in consumption. Results There were 935 firework-related injuries reported to the NEISS from 2018 to 2020, 47% of which occurred during 2020. National estimates for monthly injuries per million were 1.6 times greater in 2020 compared to 2019 (p < 0.0001) with no difference between 2018 and 2019 (p = 0.38). The same results were found when the month of July was excluded. Firework consumption in 2020 was 1.5 times greater than 2019 or 2018, with a 55% increase in consumer fireworks and 22% decrease in professional fireworks sales. Conclusions Firework-related injures saw a substantial increase in 2020 compared to the two years prior, corroborated by a proportional increase in consumer firework sales. Increased incidence of firework-related injuries was detected even with the exclusion of the month of July, suggesting that the COVID-19 pandemic may have impacted firework epidemiology more broadly than US Independence Day celebrations.


2010 ◽  
Vol 25 (3) ◽  
pp. 409-419 ◽  
Author(s):  
Natalia Linos ◽  
Marwan Khawaja ◽  
Mohannad Al-Nsour

The aim of this study is to examine attitudes among married women toward wife beating and to investigate the hypothesis that female individual empowerment is associated with such attitudes within a broader context of societal patriarchy in Jordan. The study uses data from a cross-sectional survey of a representative sample of married women (n = 5,390) conducted in 2002. Associations between acceptance of wife beating and several women’s empowerment variables, including decision-making power, as well as other risk factors were assessed, using odds ratios from binary logistic regression models. The key finding is that the vast majority (87.5%) of Jordanian women believe that wife beating is justified in at least one hypothetical scenario, and justification is negatively associated with empowerment variables and some demographic, geographic, and socioeconomic factors.


2018 ◽  
Vol 34 (3) ◽  
pp. 234-242
Author(s):  
Martin F. Cohen ◽  
Sarah M. Irie ◽  
C. Allison Russo ◽  
Veronika Pav ◽  
Shannon L. O’Connor ◽  
...  

The Centers for Medicare & Medicaid Services (CMS) has been providing data to organizations participating in a range of innovation models to help them implement interventions and to provide feedback on performance. The authors studied 18 CMS models to gain a better understanding of factors contributing to model participants’ use or nonuse of CMS-provided data. Factors that contribute to greater use include providing data that participants view as actionable, some type of accountability for performance, robust learning support, participants having resources to work with the data, and soliciting ongoing feedback about the data and related learning needs. Factors that discourage data uptake include time lag, lack of aggregated multi-payer data, exclusion of data for sensitive diagnoses, and small sample sizes. Claims-based data from payers can be an important source of information to innovation model participants. Lessons from this study can increase the usefulness of such data.


2018 ◽  
Vol 2 (1) ◽  
pp. 96-104 ◽  
Author(s):  
Md. Abdur Rouf

Purpose This paper aims to determine the influence of various corporate characteristics such as total assets (TA), total sales (TSE), return on assets (ROA), return on sales (ROS), liquidity and age on leverage of the listed non-financial companies in the Dhaka Stock Exchange (DSE). Design/methodology/approach A non-probability sampling technique has been used in this study, and the leverage of 106 companies listed in the DSE has been examined for the time period 2011-2015. Multiple regression models are used to estimate the influence of corporate characteristics on leverage and leverage is measured by the debt ratio, that is, total liabilities divided by total assets (TA). Findings The results obtained from the regression models show that TA, ROA and age are negatively and significantly related to the leverage of companies. Research limitations/implications Considering only non-financial companies as the sample is a limitation. Hence, the results may not extend across all listed companies in Bangladesh. The study explores only six corporate characteristics variables; other factors influencing the leverage of the firm such as the number of foreign shareholders, ownership structure and auditors’ opinion could be explored in further studies. Originality/value The finding of this study contributes to the regulators and enforcement agencies such as Institute of Cost and Management Accountants of Bangladesh (ICMAB), Institute of Chartered Accountants of Bangladesh (ICAB), the Securities and Exchange Commission (SEC) and the DSE. It will enable the regulatory agencies to aim at greater compliance with the local and international standards and also enforce penalties for non-compliance.


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