Differences in levels of E. coli contamination of point of use drinking water in Bangladesh.

This study aimed to quantify the inequalities and identify the associated factors of the UN sustainable development goal (SDG) targets in relation to safe drinking water. The concentration of the gut bacterium Escherichia coli in drinking water at the point of use (POU) and other information were extracted from the latest wave of the nationally representative Bangladesh Multiple Indicator Cluster Survey (MICS 2019). Bivariate and multivariable multinomial logistic regression models were used to identify potential predictors of contamination, whereas, classification trees were used to determine specific combinations of background characteristics with significantly higher rates of contamination. A higher risk of contamination from drinking water was observed for households categorized as middle or low wealth who collected water from sources with higher concentrations of E. coli. Treatment of drinking water significantly reduced the risk of higher levels of contamination, whereas owning a pet was significantly associated with recontamination. Regional differences in the concentrations of E. coli present in drinking water were also observed. Interventions in relation to water sources should emphasize reducing the level of E. coli contamination. Our results may help in developing effective policies for reducing diarrheal diseases by reducing water contamination risks.

Injury risk associated with physical demands and school environment characteristics among a cohort of custodial workers.

Few epidemiological studies have investigated the relationship between work exposures and injury risk among custodians. The relationship between injury risk and occupational physical demands (e.g. pushing/pulling, lifting) and school environment characteristics (e.g. school type, season) was investigated among a cohort of 581 school custodians over a 4-year period. In the final Poisson regression models, the risk of injury was associated with time spent in pushing/pulling tasks in a dose-response manner increasing to a five-fold risk among the highest quartile of exposure (risk ratio = 5.15, 95% CI 1.00, 26.5). Injury risk was also associated with working during the school year compared to the summer, working in a school with grass vs. gravel grounds and working in a school with detached classrooms. Results help to target interventions such as alternative methods for floor cleaning to reduce the pushing/pulling demands of custodial work and to support decisions for alternatives to detached classrooms and grass surfaces. Statement of Relevance: This study examines ergonomic factors (physical demand exposures, school environment characteristics) associated with injury risk among custodial school workers. The findings help schools to target interventions to reduce the physical demands associated with injuries and to design school environments to reduce exposures.

Correlates of smoking among adolescents with asthma.

AIMS AND OBJECTIVE: This study examined the correlates of smoking among asthmatic adolescents to gain a better understanding of who is at particular risk. BACKGROUND: Smoking is especially harmful to individuals with asthma. However, smoking is surprisingly prevalent among asthmatic individuals, with prevalence rates similar to or higher than those of the general adult or adolescent populations. Despite this notable finding, there has been little research about factors (i.e. biophysical, psychosocial and behavioural) influencing asthmatic adolescents' tobacco use patterns. DESIGN: A Canadian provincial cross-sectional survey. METHOD: The study about adolescents' tobacco use and health status was conducted in secondary schools in 2004, 608 asthmatic adolescents participated. Demographic factors, biophysical (body mass index and physical health), psychosocial factors (parents' and peers' smoking, environmental tobacco smoke exposure and depression) and behavioural factors (marijuana use, alcohol use and exercise frequency) were explored. Multinomial logistic regression analyses were conducted to identify risk factors associated with tobacco use. RESULTS AND CONCLUSIONS: Of the 608 asthmatic adolescents, 17.4% currently smoked and 12.0% formerly smoked. Girls, compared with boys, were more likely to smoke (OR: 3.34, 95% CI: 1.62-6.96) after adjusting for differences in the other demographic, biophysical, psychosocial and behavioural factors. Asthmatic girls who had relatively higher body mass index, were in the higher school grades, used marijuana or alcohol, had minor to severe depressive symptoms, had environmental tobacco smoke exposure in their homes and had friends who smoked or were currently more likely to smoke. The former smokers had similar risk factors including higher body mass index, environmental tobacco smoke exposure at home, friends who smoked and marijuana use. RELEVANCE TO CLINICAL PRACTICE: Despite their health condition, asthmatic adolescents continue currently or formerly to smoke. Gender appropriate prevention and cessation interventions for asthmatic adolescents may need to address important psychosocial and environmental factors that increase the risk of these adolescents initiating and maintaining tobacco use.

Impact of genotype misclassification on genetic association estimates and the bayesian adjustment.

Genotypes of single nucleotide polymorphisms are subject to misclassification. If ignored, such misclassification can seriously distort the estimated genotype effects on the disease or outcome of interest. Validation data (gold standard or replicated surrogates) are required to assess the degree of misclassification and make adjustments. In practice, gold standard measurements may be unavailable or impractical. Collecting replicated surrogates is a reasonable option for validation data. In most practical applications, collecting replicated surrogates on all study subjects is not feasible; however, obtaining replicated surrogates on a subsample of the study population may be quite feasible. Generating duplicate data for a subsample of the study population is now common practice among genotyping laboratories. The authors propose a Bayesian method that can adjust for genotype misclassification using partial validation data. Simulation results show that the proposed method substantially reduces misclassification bias from the estimated genotype-disease association and provides appropriate uncertainty assessment, as well as improves other desirable properties of the estimated effects. The authors also provide an example showing the application of the proposed method to study data relating non-Hodgkin lymphoma to a single nucleotide polymorphism in the aryl hydrocarbon receptor gene.

Modeling influences on acute care nurses' engagement in tobacco use reduction.

Although nurses are encouraged to address patients' tobacco use, the integration of tobacco reduction into practice has not been consistent. An organizational behavior perspective was used to conceptualize hypothesized relationships among reported influencing factors (individual characteristics, role attitudes, perceived barriers, and workplace climate). Survey data collected at two Western Canadian hospitals (N = 214 nurses; 58% response) were used to test the model. The final model explained nearly 60% of variation in the nurses' tobacco reduction practice. Role attitude, perceived resource availability, co-worker's activities, and ability were the strongest contributors. Nurses' smoking status indirectly influenced practice through shaping role attitudes and perceived ability. Diverse leverage points to enhance nurses' involvement in patients' tobacco use were identified.

Community mental healthcare providers' attitudes and practices related to smoking cessation interventions for people living with severe mental illness.

OBJECTIVE: This study aimed to describe mental healthcare providers' attitudes about tobacco use, their personal smoking status, their confidence in offering smoking cessation support to clients living with severe mental illness, and the extent to which they incorporated smoking cessation interventions into their practice. The study also aimed to determine whether the providers' attitudes, smoking status, and confidence were associated with offering smoking cessation support to clients. METHODS: Self-administered questionnaires were distributed within community-based mental health agencies to those who provide care and support to adults living with severe mental illness. Outcomes measured included respondents' smoking status, attitudes related to the provision of smoking cessation support, confidence in providing smoking cessation intervention, and smoking cessation practices. We conducted multivariate analyses using logistic regression analyses to examine the factors associated with the providers' tobacco-related practices. RESULTS: In total 282 of 871 care providers responded to the survey, 22% of whom were current smokers. The providers who held sympathetic attitudes about their role and their clients' role in smoking cessation, who were never or former smokers, who were healthcare professionals rather than paraprofessionals, who had relatively more confidence, and who had more experience working in the mental health field were more likely to engage their clients in tobacco-related interventions. CONCLUSIONS: In this study the healthcare providers working in community-based mental health have a smoking prevalence rate that exceeds that of the region's general population and did not provide optimal smoking cessation support to their clients. PRACTICE IMPLICATIONS: Interventions that bolster the confidence of providers to engage is smoking cessation activities and that support a shift in attitudes about the role of tobacco use in mental health are required.

Ethnic and gender differences in patient education about heart disease risk and prevention.

OBJECTIVE: To investigate whether there are gender and ethnic disparities in the patient education provided by primary healthcare providers about heart disease (HD) risk and prevention. METHODS: A telephone survey, conducted in four languages, was completed by 976 people, 40+ years of age, in Metro Vancouver, Canada. Questions assessing communication with healthcare providers' provision of HD risk and management education were the focus. RESULTS: Statistically significant gender and ethnic differences were found. Women were less likely to report discussing HD risk and management with their healthcare providers. Chinese-Canadian participants had less likelihood of receiving HD education compared with participants of other ethnic origins. These differences persisted after multivariate adjustment with income, highest level of education attained, age, and other factors. CONCLUSION: Primary healthcare providers should make improved efforts towards education about HD and its risk factors for women in general, and for postmenopausal women especially. PRACTICE IMPLICATIONS: Healthcare providers should be aware that some ethnic populations may not be receiving patient education similar to that received by people of other communities, as found for Chinese-Canadian members of this study community. Further understanding of the barriers faced by ethnic groups must be gained to develop solutions.

Bayesian adjustment for covariate measurement errors: a flexible parametric approach.

In most epidemiological investigations, the study units are people, the outcome variable (or the response) is a health-related event, and the explanatory variables are usually environmental and/or socio-demographic factors. The fundamental task in such investigations is to quantify the association between the explanatory variables (covariates/exposures) and the outcome variable through a suitable regression model. The accuracy of such quantification depends on how precisely the relevant covariates are measured. In many instances, we cannot measure some of the covariates accurately. Rather, we can measure noisy (mismeasured) versions of them. In statistical terminology, mismeasurement in continuous covariates is known as measurement errors or errors-in-variables. Regression analyses based on mismeasured covariates lead to biased inference about the true underlying response-covariate associations. In this paper, we suggest a flexible parametric approach for avoiding this bias when estimating the response-covariate relationship through a logistic regression model. More specifically, we consider the flexible generalized skew-normal and the flexible generalized skew-t distributions for modeling the unobserved true exposure. For inference and computational purposes, we use Bayesian Markov chain Monte Carlo techniques. We investigate the performance of the proposed flexible parametric approach in comparison with a common flexible parametric approach through extensive simulation studies. We also compare the proposed method with the competing flexible parametric method on a real-life data set. Though emphasis is put on the logistic regression model, the proposed method is unified and is applicable to the other generalized linear models, and to other types of non-linear regression models as well.

Ethnic and gender differences in perceptions of mortality risk in a Canadian urban centre.

BACKGROUND: Women reportedly do not perceive heart disease (HD) as a major threat to their health; however, men's perceptions are rarely studied. PURPOSE: We explored gender and ethnic differences in risk perception of HD mortality. METHODS: The survey was completed by 976 people 40+ years of age, in metropolitan Vancouver, Canada. RESULTS: Men, compared with women, were more likely not to know the answer to a question about whether HD is the most common cause of death for women; however, women were more likely not to know the answer to a question about whether HD is the most common cause of death for men. Chinese-Canadian and South Asian-Canadian participants were more likely than participants of other ethnic groups not to know the answer to either question, and the Chinese-Canadian participants were more likely to disagree that HD is the most common cause of death for women. CONCLUSION: There is a need to educate the Chinese-Canadian and South Asian-Canadian communities about HD as a first step in promoting health behavior change. Men and women must be educated about the other gender's risk of HD because all adults play integral roles in making decisions about the prevention of and early intervention for HD.