The role of occupational exposures in the genesis of airways disease may be underestimated in workforce studies because of the "healthy" worker effect, due either to those with more resistant airways entering a workplace or those with work related airways disease changing or quitting their job. Both effects are minimised in population-based studies which have the disadvantage that occupational exposures are of necessity self-reported. The overall goal of this research was to develop and validate an instrument to measure occupational exposures in epidemiologic research in general population studies of airways disease. / The study hypothesis was that self-reported exposure information pertinent to airway disease was as accurate a reflexion of exposure as information derived from industrial hygiene expertise. To examine the study hypothesis, use was made of occupational questionnaires completed by 338 adults participating in a Montreal community based study. A list of 927 reported jobs was submitted for coding of exposures to 2 industrial hygienists working independently to code exposures. / Intra-subject reproducibility of questionnaire information, assessed using a test-retest approach in 33 subjects showed good overall concordance for most components of the work history. Inter-rater reliability (between hygienists) was also good for some categories of exposures. / Validity analysis of self-reported exposure, using as a reference criterion the exposure coding by either hygienist lead to poor values for sensitivity and phi-coefficients but not for specificity. Slight improvement in sensitivities and phi-coefficients was found for latest job. / While smoking, a family history and atopy were determinants of asthma in multivariate models, significant exposure response relationships were obtained only with self reported exposure, not with exposures coded by either hygienist. Nevertheless the coefficients and confidence intervals for self-reported exposures were, for most part, in the same direction and range as those for exposure coded by the 2 hygienists. / These results are consistent with the study hypothesis that self reported exposures perform comparably, possibly even better than exposures based on industrial hygiene expertise in characterising exposure response relationships for airway disease in community based studies.

<p> Workers' compensation programs have emerged as among the largest and most important social programs in the United States. Workers' compensation claims in the state of Michigan account for an expenditure of approximately 1.3 billion dollars annually (Michigan Workers' Compensation Agency, 2011. 2011 <i>Annual Report</i>). Back injuries are the most prevalent work-related injury in the United States. Since 2002, such injuries in the baby-boomer generation have increased at a rate of 50% (Toossi, 2005. <i> Labor force projections to 2014: Retiring boomers</i>). The purpose of this study is to describe the personal lived experiences of older (over 55 years old) injured employees as a result of injuring their lower backs at work. The study only examined occupational lower back injuries suffered while assembling automotive parts in the state of Michigan. The study incorporates a qualitative design, specifically an interpretative phenomenological analysis, to focus on the lived experiences of the participants, and underpins the theory of planned behavior to assist with forecasting and understanding the particular behaviors within this population. A four-step data analysis method was used to illustrate and understand the meaning and essence of the lived experience of the injured, older automobile assembler worker.</p>

<p> <i>Background.</i> Nursing assistants, working in long&ndash;term care facilities, have consistently been among the top occupational groups experiencing work-related musculoskeletal injuries. These injuries have been attributed the physical demands of lifting and moving the individuals in their care. Great strides in research have identified successful risk reduction strategies such as the implementation safe patient handling and mobility programs. The benefits of these programs have been advocated over the last two decades, but the rate of injuries among nursing assistants continues to be more than double the national average for all other industries. The purpose of this study was to investigate the influence of safe patient handling and mobility policies and procedures, facility resources, and work practices on the trends in injury rates and the associated costs in long-term care facilities.</p><p> <i>Methods.</i> Thirty-eight facilities contributed information to the study. Data were gathered on safe patient handling policies, facility resources, work practices, work-related injuries and workers&rsquo; compensation costs for 2002 &ndash; 2011.</p><p> <i>Results.</i> Eighty-four percent of the facilities had patient handling policies or were preparing to implement in the upcoming year. All of the facilities had mechanical lifting devices, employee training and procedures for embedding safe patient handling into daily work practices. Nineteen facilities contributed one to ten years of data, showing injury rates decreased 63% from 2002 &ndash; 2011. Eleven facilities provided worker&rsquo;s compensation information showing medical and indemnity costs decreased 54% from 2006 &ndash; 2011. The presence of a policy, was not found to independently influence these factors. The number of days away from work due to work-related injuries was significantly lower in facilities with patient handling policies. <i> Conclusion.</i> The presence of the policy was not found to independently influence injury rates or costs, but the prevalence of safe patient handling policies, mechanical lifting devices and safe work practices suggested that a safety culture may finally be present in long-term care. Despite the impressive reductions in injuries and costs, the continued higher than average rate of injuries among this occupational group may indicate that other factors now play a greater role in work-related injuries.</p>

<p> Objectives: The purpose of this secondary data analysis was to examine "stage of change" as a predictor of attrition among participants in a worksite wellness program. A Conceptual Model of Attrition was developed to examine health screening, health risk appraisal (HRA), and demographic predictors of attrition as well. Methods: Data for this study were drawn from a worksite wellness program which was sponsored by an integrated rural healthcare system. The sample consisted of 1058 individuals for whom valid demographic, health screening, and HRA data were available. Of the total sample, 414 did not participate in a subsequent year (39.1% attrition). This research was conducted as a predictive correlational study using binary logistic regression analysis. Results: Significant associations between stage of change and attrition were found for the physical activity, nutrition, weight, stress, and overall healthy lifestyle health behavior areas. The stage of change with the highest odds of attrition was the preparation stage across these health behavior areas. In the Conceptual Model of Attrition, significant associations with attrition were found for emotional symptoms, emotional health limitations, health view, and overall healthy lifestyle stage of change. Conclusions: This research has shown that the stage of change construct is useful for predicting attrition. Identification of participants' stage of change offers a leverage point for engagement in worksite wellness programs and for prevention of program attrition. For employers, retention of these employees in their worksite wellness program could yield a greater return on investment resulting in lower health care costs, fewer missed work days, and higher productivity on the job.</p>

In spite of the vast technological progress and improvement in the standard of management systems within hazardous industries around the world, occupational health and safety incidents and fatalities continue to devastate thousands of lives each year. Throughout the last decade, significant improvement has been achieved in the reduction of health and safety incident rates across the South African petrochemical environment. However, a persistent roller-coaster fatality rate still prevails. Recent studies have shown that in order to conquer the relentless battle in realizing sustainable world-class health and safety performance, an organisation has to move beyond the traditional compliance orientated safety focus towards an interdependent safety culture in which safety is ubiquitous and embedded in the hearts of all employees. The root causes of more and more occupational health and safety incidents are no longer as a result of mechanical or systems failure, but instead originate from the attitude, values and beliefs of management and employees with regard to the significance of safety, also known as the safety culture. This has ignited a rising interest in the concept of safety culture among organisations because of the positive impact on occupational health and safety in reducing the potential for fatalities, injuries and workplace incidents. Hence the primary objective of this study is to determine the maturity of the current safety culture in the South African petrochemical environment by identifying particular culture shortfalls which could lead to hesitant progress towards the desired interdependent state. In order to reach this objective, three secondary objectives have also been set. Firstly, an understanding of the concept of organisational culture and safety culture is crucial. In simple terms, organisational culture can be described as the shared values, assumptions and beliefs in an organisation that ultimately direct employee behaviour. Organisational culture is characterised by three layers known as artefacts, espoused values and basic assumptions. These layers represent the manifestation of the organisational culture and vary in terms of outward visibility and resistance to change. Understanding and analysing these layers provide the reasons why employees behave in certain ways. Safety culture is a subset of organisational culture; in other words, it is the manifestation of the organisation?s attitude, values and commitment in regard to the importance of health and safety. Companies which have developed effective safety cultures have demonstrated unequivocal results in closing the elusive health and safety performance gap. Secondly, the fundamental components conducive of an effective safety culture were explored. These components include management and employee commitment to health and safety, accountability and involvement, communication and trust, risk awareness and compliance, competency and learning and finally recognition. Most of the components can be assigned to the artefact level or a combination of the level of artefacts and espoused values with only a small number more appropriately associated with the level of basic assumptions. The effectiveness within each of these areas ultimately dictates the nature of the safety culture and the success in preventing health and safety incidents. The focus of the last secondary objective was to determine the development stages leading to an effective safety culture known as an interdependent safety culture. Each of these stages represents the degree of maturity of the attitudes and commitment of management and employees in relation to the ongoing health and safety improvement in the organisation. The DuPont model suggests that in a reactive safety culture, safety is merely a natural instinct with no real perceived value for the individual or organisation. Moving towards a dependent safety culture, employees start to value safety but only so they do not get caught. The next stage called an independent safety culture is characterised by self preservation. In this stage, the mindset of employees changed towards an attitude of ?I do things safe so I do not get hurt?. In the final stage known as interdependent safety culture, employees embrace safety as a personal virtue not only for their own safety but also in contribution to the safety of their peers. In such a culture it is employees? desire to do things safely so that no-one gets hurt. An empirical study was conducted through a quantitative research approach in the form of a safety climate questionnaire. The target population consisted of first-line managers and non-managerial personnel within the production; maintenance; laboratory; technical, and the safety, health and environment departments in a petrochemical organisation. In light of the results emanating from the empirical study it can be concluded that an overall positive perception was observed towards the selected safety culture components indicative through the mean response scores above the neutral scale of 3. Older and more experienced employees demonstrated a more positive response to the safety compared to younger employees. However, several distinctive safety culture shortcomings were also identified. In the current safety culture, health and safety is sometimes overlooked due to productivity or cost implications. Employees tend to withhold safety related information to themselves as a culture of guilt prevails and mere compliance to safety standards is considered adequate. Solutions to health and safety problems are most of a short-term nature and do not address the root cause. It therefore provides evidence that the organisation under evaluation has not yet reached the desired safety culture maturity stage of interdependence. Although the study population is limited to a single organisation, the shortfalls identified could relate to the larger petrochemical environment and thus could explain the recent fluctuating health and safety performance. This assumption, however, can only be validated through further research within a much greater sample size inclusive of more than one organisation in the petrochemical environment. It is thus clear that the existing safety culture within the petrochemical organisation could lead to potential health and safety incidents if the shortcomings are not appropriately addressed. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2011.

<p> Several lines of evidence suggest that pigs act as a reservoir of hepatitis E virus (HEV). This dissertation presents data from studies conducted from August 2010 &ndash; August 2011 in Nan, Thailand. These studies define the previously unknown burden of HEV in pig and human populations in Nan province, and evaluate the transmission of HEV among humans having direct or indirect contact with the reservoir in pig. This work begins with a literature review. The first study addressed the risks for HEV transmission between pigs in different sized farms, and possible risk factors among pigs in a cross-sectional study. This study found a 9.9% (87/879) seroprevalence of anti-HEV among pigs and 2.9% of pigs had HEV ribonucleic acid (RNA) positive fecal samples. All HEV sequences corresponded to genotype 3. Pigs raised on medium sized farms with 30-300 pigs per farm had higher anti-HEV seroprevalence than pigs raised on larger farms with over 300 pigs after controlling for other potential confounders. Better hygienic practices were used in larger farms compared with small or medium sized farms. The second study addressed the association between occupational pig exposure to HEV infection among farmers over the age of 15 and the general population without direct contact with pigs in a cross-sectional study. The overall prevalence of anti-HEV was 23.0% (118/513). There was no association between anti-HEV prevalence and direct exposure to pigs. Frequent consumption of organ meat &ge; 2 times per week was a significant risk factor for HEV seroprevalence, adjusted odds ratio (OR) 3.23, 95% confidence interval (CI) 1.15, 9.01. Serum samples from all subjects with recent symptoms compatible with hepatitis who were IgM anti-HEV positive among the farmers and 40 serum samples from the control unexposed group with the highest mean optical density (OD) value were evaluated for HEV RNA by reverse transcriptase polymerase chain reaction (RT PCR). None of the samples were HEV RNA positive. These studies establish that HEV is endemic among pig populations in Nan province. It appears that HEV infections in humans are acquired more frequently as a food-borne infection than by direct contact with pigs in this population. </p>

In spite of the vast technological progress and improvement in the standard of management systems within hazardous industries around the world, occupational health and safety incidents and fatalities continue to devastate thousands of lives each year. Throughout the last decade, significant improvement has been achieved in the reduction of health and safety incident rates across the South African petrochemical environment. However, a persistent roller-coaster fatality rate still prevails. Recent studies have shown that in order to conquer the relentless battle in realizing sustainable world-class health and safety performance, an organisation has to move beyond the traditional compliance orientated safety focus towards an interdependent safety culture in which safety is ubiquitous and embedded in the hearts of all employees. The root causes of more and more occupational health and safety incidents are no longer as a result of mechanical or systems failure, but instead originate from the attitude, values and beliefs of management and employees with regard to the significance of safety, also known as the safety culture. This has ignited a rising interest in the concept of safety culture among organisations because of the positive impact on occupational health and safety in reducing the potential for fatalities, injuries and workplace incidents. Hence the primary objective of this study is to determine the maturity of the current safety culture in the South African petrochemical environment by identifying particular culture shortfalls which could lead to hesitant progress towards the desired interdependent state. In order to reach this objective, three secondary objectives have also been set. Firstly, an understanding of the concept of organisational culture and safety culture is crucial. In simple terms, organisational culture can be described as the shared values, assumptions and beliefs in an organisation that ultimately direct employee behaviour. Organisational culture is characterised by three layers known as artefacts, espoused values and basic assumptions. These layers represent the manifestation of the organisational culture and vary in terms of outward visibility and resistance to change. Understanding and analysing these layers provide the reasons why employees behave in certain ways. Safety culture is a subset of organisational culture; in other words, it is the manifestation of the organisation?s attitude, values and commitment in regard to the importance of health and safety. Companies which have developed effective safety cultures have demonstrated unequivocal results in closing the elusive health and safety performance gap. Secondly, the fundamental components conducive of an effective safety culture were explored. These components include management and employee commitment to health and safety, accountability and involvement, communication and trust, risk awareness and compliance, competency and learning and finally recognition. Most of the components can be assigned to the artefact level or a combination of the level of artefacts and espoused values with only a small number more appropriately associated with the level of basic assumptions. The effectiveness within each of these areas ultimately dictates the nature of the safety culture and the success in preventing health and safety incidents. The focus of the last secondary objective was to determine the development stages leading to an effective safety culture known as an interdependent safety culture. Each of these stages represents the degree of maturity of the attitudes and commitment of management and employees in relation to the ongoing health and safety improvement in the organisation. The DuPont model suggests that in a reactive safety culture, safety is merely a natural instinct with no real perceived value for the individual or organisation. Moving towards a dependent safety culture, employees start to value safety but only so they do not get caught. The next stage called an independent safety culture is characterised by self preservation. In this stage, the mindset of employees changed towards an attitude of ?I do things safe so I do not get hurt?. In the final stage known as interdependent safety culture, employees embrace safety as a personal virtue not only for their own safety but also in contribution to the safety of their peers. In such a culture it is employees? desire to do things safely so that no-one gets hurt. An empirical study was conducted through a quantitative research approach in the form of a safety climate questionnaire. The target population consisted of first-line managers and non-managerial personnel within the production; maintenance; laboratory; technical, and the safety, health and environment departments in a petrochemical organisation. In light of the results emanating from the empirical study it can be concluded that an overall positive perception was observed towards the selected safety culture components indicative through the mean response scores above the neutral scale of 3. Older and more experienced employees demonstrated a more positive response to the safety compared to younger employees. However, several distinctive safety culture shortcomings were also identified. In the current safety culture, health and safety is sometimes overlooked due to productivity or cost implications. Employees tend to withhold safety related information to themselves as a culture of guilt prevails and mere compliance to safety standards is considered adequate. Solutions to health and safety problems are most of a short-term nature and do not address the root cause. It therefore provides evidence that the organisation under evaluation has not yet reached the desired safety culture maturity stage of interdependence. Although the study population is limited to a single organisation, the shortfalls identified could relate to the larger petrochemical environment and thus could explain the recent fluctuating health and safety performance. This assumption, however, can only be validated through further research within a much greater sample size inclusive of more than one organisation in the petrochemical environment. It is thus clear that the existing safety culture within the petrochemical organisation could lead to potential health and safety incidents if the shortcomings are not appropriately addressed. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2011.

The occupational environment has been a fruitful source of research on causes of cancer. Analyses in studies of occupational risk factors for cancer can experience problems if an attempt is made to model large numbers of exposures, some of which may be highly correlated. Typical analyses of such studies focus on one chemical at a time, but this may not adequately deal with mutual confounding. Based on a large study in Montreal, the objective of this thesis was twofold: to assess several occupational chemicals for their etiologic role in lung cancer, and to explore the use of semi-Bayes modeling to simultaneously estimate the effects of many chemicals at a time. Methods. Data came from a multiple-cancer case-control study of exposures in the work place. The study was comprised of 857 cases of lung cancer and 2172 controls consisting of patients with other types of cancer diagnosed from 1979 to 1985. Detailed occupational histories were collected and occupational hygienists translated these into exposure histories for 231 chemicals. All chemicals were analysed with conventional modeling strategies of both single and multiple parameter models. Of the 231 chemicals, 184 were singled out for analysis in a single large semi-Bayes model, which is a variant of classical empirical Bayes. This analysis is a fairly novel method suited to estimating large numbers of parameters in the face of sparse data. For the Bayesian portion of this model, chemicals were grouped by shared chemical and physical properties, based on the belief that these shared properties would imply similar effects on the risk of lung cancer. Results. Estimates for all 231 chemicals were derived under the various modeling strategies. For most chemicals, estimates changed little across these analytic approaches, though some differences were apparent. Of the 231 chemicals assessed, 53 were earmarked as requiring further evaluation and underwent additional analyses. Discussion. While semi-Bayes models have been shown previously to offer improved estimation over conventional analyses, the gains in using semi-Bayes models in the present study were less clear. Effort put into some portions of the Bayesian modeling did not materially influence the results. A number of chemicals were earmarked as potential lung carcinogens.

This thesis explores the occupational health and safety risks facing labour hire employees (also known as temporary agency workers) in the Australian state of Victoria. Three questions are considered. First do labour hire employees face greater risk of injury and disease than direct hire employees? Second, if so, which characteristics of labour hire employment contribute to a higher rate of injury? Third, what characteristics of labour hire employment reduce the likelihood of injured employees returning to work and being rehabilitated? The first question is answered by an aggregate analysis of data drawn from all workers' compensation claim files in Victoria between 1994/5 and 2000/1 contrasting the frequency of injury for both temporary agency employees and direct hire employees. Second a unique sub sample of individual investigated claim files was then examined to test employment factors that could account for the higher frequency of injury amongst agency workers. A third data source involved a survey and focus groups of temporary agency workers. This provided supplementary data on the work experiences of labour hire employees. A number of conclusions are drawn. Labour hire employees are more likely to be injured at work than their direct hire counterparts. Factors explaining this include economic pressures, disorganisation at the host workplace, and regulatory failure for agency employees. Several of these factors are uniquely related to the triangular nature of labour hire arrangements. Once injured at work, labour hire employees are especially disadvantaged relative to direct hire employees through the reluctance of many labour hire employers to offer further employment. This reduces the capacity of labour hire workers to return to meaningful employment. Regulatory failure stemming from both employment and occupational health and safety legislation underpins the greater likelihood of agency workers being injured at work and then dispensed with by employers. Until the uniqueness of their triangular relationship with employers and hosts is recognised through appropriate regulatory intervention, their greater occupational health and safety risks will not be overcome.

Doctor of Philosophy(PhD) / Background: There is no on-going information on the number, rate or circumstances of work-related fatal injury in Australia. This thesis reports on a study aimed to identify and describe all work-related fatalities that occurred in Australia during the four-year period 1989 to 1992, in order to make a significant contribution to the effectiveness of activity designed to prevent work-related traumatic death. Methods: A broad definition of work was used, with particular focus on workers and bystanders. The study also included the injury-related deaths of volunteers, students, persons performing home duties and persons fatally injured on farms but not due to obvious farm work. The data were obtained primarily from coronial files. Files were found for 99.7% of the deaths of interest. Detailed results are presented on the work-related deaths of workers, bystanders and persons fatally injured while engaged in home duties. The results for workers are also compared with those from an earlier study of work-related fatalities in Australia, which covered the years 1982 to 1984 inclusive. Other aspects of work-related deaths are considered in detail, including the effect of employment arrangements; their coverage by occupational health and safety and compensation agencies; their handling by the coronial system; the role of External Cause codes in identifying and monitoring work-related injury deaths; and the reliability and validity of the definitions used to classify work-related injury deaths. Results: There were 2,413 persons fatally injured while working or commuting during the study period (1,787 working; 626 commuting), with a rate of death for working persons of 5.5 per 100,000 persons per year. This compared to the rate of 6.7 for working deaths during 1982 to 1984, with just under half of the decline probably due to changes in the industry distribution of the workforce. Another 802 persons were fatally injured as a result of someone else’s work activity, and 296 persons aged 15 years and over were fatally injured while undertaking active tasks in an unpaid and informal capacity in their own home or in someone else’s home. Thirty-four percent of working deaths were not covered by either occupational health and safety (OHS) or compensation agencies. A consideration of External Cause codes for the period 1979 to 1997 inclusive suggested there was a yearly decrease in the rate of workplace deaths of 2.6% per year, with less than half of this change due to industry changes in the workforce. Deaths occurring in a small number of particular circumstances were found to pose classification problems. Conclusion: Fatal work-related trauma remains an important problem for the Australian community. By understanding how and why these deaths occur, appropriate steps can be taken to prevent similar incidents recurring. It is expected that the results reported here, and other information that has arisen from the study, will make an important contribution to developing this understanding and preventing the occurrence of work- related traumatic death in Australia.