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Reports on consultations held with four communities in Ontario as part of the development of health-based indicators of air quality. Relationships between air pollution and adverse health impacts; Improvements in self-reported ability of participants to assess and use air quality indicators; Suggestions for resolving tensions inherent in the development of environmental health indicators.

Scholarship on the health impacts of resource extraction displays prominent gaps and apparent corporate and neocolonial footprints that raise questions about how science is produced. We analyze production of knowledge, on the health impacts of mining, carried out in relation to the Canadian International Resources and Development Institute (CIRDI), a university-based organization with substantial extractive industry involvement and links to Canada's mining-dominated foreign policy. We use a "political ecology of knowledge" framework to situate CIRDI in the context of neoliberal capitalism, neocolonial sustainable development discourses, and mining industry corporate social responsibility techniques. We then document the interactions of specific health disciplinary conventions and knowledges within CIRDI-related research and advocacy efforts involving a major Canadian global health organization. This analysis illustrates both accommodation and resistance to large-scale political economic structures and the need to directly confront the global North governments and sectors pushing extractive-led neoliberal development globally. Resumen La investigación sobre los impactos en la salud de la extracción de recursos naturales delata brechas importantes y huellas corporativas y neocoloniales, que plantean dudas acerca de cómo se produce la ciencia. Analizamos la producción de conocimiento sobre los impactos en la salud de la minería en relación con el Instituto Canadiense de Desarrollo y Recursos Internacionales (CIRDI, siglas en inglés), una organización universitaria que cuenta con participación sustancial de la industria extractiva y tiene vínculos con la política exterior de Canadá, la cual es dominada por intereses mineros. Utilizamos un marco de "ecología política del conocimiento" para situar a CIRDI en el contexto del capitalismo neoliberal, los discursos neocoloniales de desarrollo sostenible y las técnicas de responsabilidad social corporativa de la industria minera. Luego, documentamos las interacciones entre los conocimientos y convenciones disciplinarias de salud dentro de los esfuerzos de investigación y promoción relacionados con CIRDI que involucran a una importante organización canadiense de salud global. Este análisis muestra tanto la complacencia como la resistencia a las estructuras políticas económicas a gran escala, y la necesidad de confrontar directamente a los gobiernos y sectores del Norte global que manejan el desarrollo neoliberal impulsado por la extracción a nivel mundial.

As a collective organized to address the education implications of calls for public health engagement on the ecological determinants of health, we, the Ecological Determinants Group on Education (cpha.ca/EDGE), urge the health community to properly understand and address the importance of the ecological determinants of the public's health, consistent with long-standing calls from many quarters-including Indigenous communities-and as part of an eco-social approach to public health education, research and practice. Educational approaches will determine how well we will be equipped to understand and respond to the rapid changes occurring for the living systems on which all life-including human life-depends. We revisit findings from the Canadian Public Health Association's discussion paper on 'Global Change and Public Health: Addressing the Ecological Determinants of Health', and argue that an intentionally eco-social approach to education is needed to better support the health sector's role in protecting and promoting health, preventing disease and injury, and reducing health inequities. We call for a proactive approach, ensuring that the ecological determinants of health become integral to public health education, practice, policy, and research, as a key part of wider societal shifts required to foster a healthy, just, and ecologically sustainable future.

Objectives: Immigrants are thought to be healthier than their native-born counterparts, but less is known about the health of refugees or forced migrants. Previous studies often equate refugee status with immigration status or country of birth (COB) and none have compared refugee to non-refugee immigrants from the same COB. Herein, we examined whether: (1) a refugee mother experiences greater odds of adverse maternal and perinatal health outcomes compared with a similar non-refugee mother from the same COB and (2) refugee and non-refugee immigrants differ from Canadian-born mothers for maternal and perinatal outcomes., Design: This is a retrospective population-based database study. We implemented two cohort designs: (1) 1:1 matching of refugees to non-refugee immigrants on COB, year and age at arrival (±5 years) and (2) an unmatched design using all data., Setting and Participants: Refugee immigrant mothers (n=34 233), non-refugee immigrant mothers (n=243 439) and Canadian-born mothers (n=615 394) eligible for universal healthcare insurance who had a hospital birth in Ontario, Canada, between 2002 and 2014., Primary Outcomes: Numerous adverse maternal and perinatal health outcomes., Results: Refugees differed from non-refugee immigrants most notably for HIV, with respective rates of 0.39% and 0.20% and an adjusted OR (AOR) of 1.82 (95% CI 1.19 to 2.79). Other elevated outcomes included caesarean section (AOR 1.04, 95% CI 1.00 to 1.08) and moderate preterm birth (AOR 1.08, 95% CI 0.99 to 1.17). For the majority of outcomes, refugee and non-refugee immigrants experienced similar AORs when compared with Canadian-born mothers., Conclusions: Refugee status was associated with a few adverse maternal and perinatal health outcomes, but the associations were not strong except for HIV. The definition of refugee status used herein may not sensitively identify refugees at highest risk. Future research would benefit from further refining refugee status based on migration experiences., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

As there are no well-established modifiable risk factors for prostate cancer, further evidence is needed on possible factors such as occupation. Our study uses one of the largest Canadian worker cohorts to examine occupation, industry, and prostate cancer and to assess patterns of prostate cancer rates. The Canadian Census Health and Environment Cohort (CanCHEC) was established by linking the 1991 Canadian Census Cohort to the Canadian Cancer Database (1969-2010), Canadian Mortality Database (1991-2011), and Tax Summary Files (1981-2011). A total of 37,695 prostate cancer cases were identified in men aged 25-74 based on age at diagnosis. Cox proportional hazards models were used to estimate hazards ratios and 95% confidence intervals. In men aged 25-74 years, elevated risks were observed in the following occupations: senior management (HR = 1.12, 95% CI: 1.04-1.20); office and administration (HR = 1.19, 95% CI: 1.11-1.27); finance services (HR = 1.09, 95% CI: 1.04-1.14); education (HR = 1.05, 95% CI: 1.00-1.11); agriculture and farm management (HR = 1.12, 95% CI: 1.06-1.17); farm work (HR = 1.11, 95% CI: 1.01-1.21); construction managers (HR = 1.07, 95% CI: 1.01-1.14); firefighting (HR = 1.17, 95% CI: 1.01-1.36); and police work (HR = 1.22, 95% CI: 1.09-1.36). Decreased risks were observed across other construction and transportation occupations. Results by industry were consistent with occupation results. Associations were identified for white-collar, agriculture, protective services, construction, and transportation occupations. These findings emphasize the need for further study of job-related exposures and the potential influence of nonoccupational factors such as screening practices., (© 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Objectives: To determine the extent, range and types of studies of differential environmental chemical exposures among non-Indigenous Canadians as a function of sex/gender and race/ethnicity., Methods: Computerized database searches were performed from November to December 2013 using Medline, Embase, CAB Abstracts, Proquest and Scopus to identify relevant studies of environmental exposures among non-Indigenous adults aged ≥18 years in Canada published between 1993 and 2013. Articles were identified for full-text review based on a screening of titles and abstracts and were excluded during this initial review if they focused on environmental exposures in the following populations: 1) Indigenous populations, 2) individuals <15 years of age, 3) pregnant women and associated negative birth outcomes, or 4) non-Canadian populations. Articles were also excluded if the primary focus was on exposures to environmental tobacco smoke, non-chemical occupational hazards, infectious diseases, noise and/or radiation. A full-text review of 78 identified articles systematically assessed how sex/gender and race/ethnicity were considered., Synthesis: Although 59% of studies stratified results by sex, less than half of these offered any explanation of differential exposures. Eighteen of the 78 studies (23%) used terms related to race/ethnicity in their participant descriptions. Of the studies that conducted subgroup analyses of exposure results by race/ethnicity (n=15), a total of 8 also included subgroup analysis by sex. Overall, 3 of the 78 (3%) articles reviewed analyzed environmental exposures as a function of sex/gender and race/ethnicity., Conclusion: The role of sex/gender and race/ethnicity in influencing environmental exposure levels among non-Indigenous Canadians has not been adequately addressed to date.

Background: Global health is increasingly a major focus of institutions in high-income countries. However, little work has been done to date to study the inner workings of global health at the university level. Academics may have competing objectives, with few mechanisms to coordinate efforts and pool resources., Objective: To conduct a case study of global health at Canada's largest health sciences university and to examine how its internal organization influences research and action., Design: We drew on existing inventories, annual reports, and websites to create an institutional map, identifying centers and departments using the terms 'global health' or 'international health' to describe their activities. We compiled a list of academics who self-identified as working in global or international health. We purposively sampled persons in leadership positions as key informants. One investigator carried out confidential, semi-structured interviews with 20 key informants. Interview notes were returned to participants for verification and then analyzed thematically by pairs of coders. Synthesis was conducted jointly., Results: More than 100 academics were identified as working in global health, situated in numerous institutions, centers, and departments. Global health academics interviewed shared a common sense of what global health means and the values that underpin such work. Most academics interviewed expressed frustration at the existing fragmentation and the lack of strategic direction, financial support, and recognition from the university. This hampered collaborative work and projects to tackle global health problems., Conclusions: The University of Toronto is not exceptional in facing such challenges, and our findings align with existing literature that describes factors that inhibit collaboration in global health work at universities. Global health academics based at universities may work in institutional siloes and this limits both internal and external collaboration. A number of solutions to address these challenges are proposed.

Background: Global health training is increasingly part of public health training in high-income countries, with placements as key components. We sought preliminary evidence of student placement experiences and learning through masters' programmes at the universities of Oxford and Toronto., Methods: In a mixed-methods design, we drew on existing programme records, student feedback surveys (Oxford only) and semi-structured interviews with graduates., Results: Students participated in practice, informed policy and conducted research across a wide variety of topics, and with a range of different tasks, mostly overseas. Building on existing collaboration- or partnership-facilitated placement setup. Clear communication and face-to-face time with organizational representatives or on-site supervisors helped clarify placement objectives. Flexibility on students' and supervisors' part enabled students to take advantage of urgent public health activities for learning. Students valued the opportunity to make cross-country comparisons, to see first-hand the role of international organizations and to learn concrete skills in project design, questionnaire formulation, qualitative and quantitative analysis and writing up., Conclusions: Placements were valuable to public health professionals in training. We encourage other programmes to share placement experience of their students, field supervisors and host organizations.

Different sets of competencies in public health, global health and research have recently emerged, including the Core Competencies for Public Health in Canada (CCPHC). Within this context, we believe it is important to articulate competencies for globalhealth practitioners-educators and researchers that are in addition to those outlined in the CCPHC. In global health, we require knowledge and skills regarding: north-south power dynamics, linkages between local and global health problems, and the roles of international organizations. We must be able to work responsibly in low-resource settings, foster self-determination in a world rife with power differentials, and engage in dialogue with stakeholders globally. Skills in cross-cultural communication and the ability to critically self-reflect on one's own social location within the global context are essential. Those in global health must be committed to improving health equity through global systems changes and be willing to be mentored and to mentor others across borders. We call for dialogue on these competencies and for development of ways to assess both their demonstration in academic settings and their performance in global health practice and research.

In May 2010, Grand Challenges Canada (GCC) was launched with the mandate to identify global challenges in health that could be supported through the Government of Canada's Development Innovations Fund (DIF: $225 million over five years). The GCC offers a potentially excellent mechanism for taking Canada's participation in global health challenges "to a higher level". Recent GCC announcements raise new questions about the emphasis being placed on technological discovery or "catalytic" research. Missing so far are opportunities that the Fund could offer in order to support innovative research addressing i) health systems strengthening, ii) more effective delivery of existing interventions, and iii) policies and programs that address broader social determinants of health. The Canadian Grand Challenges announced to date risk pushing to the sidelines good translational and implementation science and early career-stage scientists addressing important social, environmental and political conditions that affect disease prevalence, progress and treatment; and the many unresolved challenges faced in bringing to scale proven interventions within resource-constrained health systems. We wish to register our concern at the apparent prioritization of biotechnical innovation research and the subordination of the social, environmental, economic and political context in which human health is either protected or eroded.

Objective: To characterize patients diagnosed with multiple chemical sensitivity (MCS), chronic fatigue syndrome (CFS), or fibromyalgia (FM), to compare their level of function with Canadian population average values, and to assess factors associated with function., Design: Chart review and abstraction of clinical information., Setting: The Environmental Health Clinic (EHC) at Women's College Hospital in Toronto, Ont, which is a provincial referral centre for patients with illnesses with suspected environmental links, especially MCS, CFS, and FM., Participants: A total of 128 consecutive patients diagnosed with 1 or more of MCS, CFS, or FM, seen between January 2005 and March 2006 at the EHC., Main Outcome Measures: Demographic and socioeconomic characteristics, comorbid diagnoses, duration of illness, health services usage, life stresses, helpful therapeutic strategies, and functional impairment measured by the Short Form-36, compared with Canadian population average values. Factors significantly associated with function in bivariate analyses were included in multiple linear and logistic regression models., Results: The patient population was predominantly female (86.7%), with a mean age of 44.6 years. Seventy-eight patients had discrete diagnoses of 1 of MCS, CFS, or FM, while the remainder had 2 or 3 overlapping diagnoses. Most (68.8%) had stopped work, and on average this had occurred 3 years after symptom onset. On every Short Form-36 subscale, patients had markedly lower functional scores than population average values, more so when they had 2 or 3 of these diagnoses. Having FM, younger age at onset, and lower socioeconomic status were most consistently associated with poor function., Conclusion: Patients seen at the EHC demonstrated marked functional impairment, consistent with their reported difficulties working and caring for their homes and families during what should be their peak productive years. Early comprehensive assessment, medical management, and social and financial support might avoid the deterioration of function associated with prolonged illness. Education and information resources are required for health care professionals and the public, along with further etiologic and prognostic research.

Objective: To evaluate the effect of the involvement of intermediaries who were research partners on three intervention studies. The projects crossed four sectors: manufacturing, transportation, service sector, and electrical-utilities sectors. The interventions were participative ergonomic programs. The study attempts to further our understanding of collaborative workplace-based research between researchers and intermediary organizations; to analyze this collaboration in terms of knowledge transfer; and to further our understanding of the successes and challenges with such a process., Participants: The intermediary organizations were provincial health and safety associations (HSAs). They have workplaces as their clients and acted as direct links between the researchers and workplaces., Methods: Data was collected from observations, emails, research-meeting minutes, and 36 qualitative interviews. Interviewees were managers, and consultants from the collaborating associations, 17 company representatives and seven researchers., Results: The article describes how the collaborations were created, the structure of the partnerships, the difficulties, the benefits, and challenges to both the researchers and intermediaries. The evidence of knowledge utilization between the researchers and HSAs was tracked as a proxy-measure of impact of this collaborative method, also called Mode 2 research., Conclusion: Despite the difficulties, both the researchers and the health and safety specialists agreed that the results of the research made the process worthwhile.

Objectives: The adverse effects of hot weather on public health are of increasing concern. A surveillance system using 911 medical dispatch data for the detection of heat-related illness (HRI) could provide new information on the impact of excessive heat on the population. This paper describes how we identified medical dispatch call codes, called "determinants", that could represent HRI events., Methods: Approximately 500 medical dispatch determinants were reviewed in focus groups composed of Emergency Medical Services (EMS) paramedics, dispatchers, physicians, and public health epidemiologists. Each group was asked to select those determinants that might adequately represent HRI. Selections were then assessed empirically using correlations with daily mean temperature over the study period (June 1-August 31,2005)., Results: The focus groups identified 12 determinant groupings and ranked them according to specificity for HRI. Of these, "Heat/cold exposure" was deemed the most specific. The call determinant groupings with the clearest positive associations with daily mean temperature empirically were "Heat/cold exposure" (Spearman's correlation coefficient (SCC) 0.71, p < 0.0001) and "Unknown problem (man down)" (SCC 0.21, p = 0.04). Within each grouping, the determinant "Unknown status (3rd party caller)" showed significant associations, SCC = 0.34 (p = 0.001) and SCC = 0.22 (p = 0.03) respectively., Conclusions: Clinically-informed expertise and empirical evidence both contributed to identification of a group of 911 medical dispatch call determinants that plausibly represent HRI events. Once evaluated prospectively, these may be used in public health surveillance to better understand environmental health impacts on human populations and inform targeted public health interventions.

Background: Public health authorities have prioritized the identification of competencies, yet little empirical data exist to support decisions on competency selection among particular disciplines. We sought perspectives on important competencies among epidemiologists familiar with or practicing in public health settings (local to national)., Methods: Using a sequential, qualitative-quantitative mixed method design, we conducted key informant interviews with 12 public health practitioners familiar with front-line epidemiologists' practice, followed by a web-based survey of members of a provincial association of public health epidemiologists (90 respondents of 155 eligible) and a consensus workshop. Competency statements were drawn from existing core competency lists and those identified by key informants, and ranked by extent of agreement in importance for entry-level practitioners., Results: Competencies in quantitative methods and analysis, critical appraisal of scientific evidence and knowledge transfer of scientific data to other members of the public health team were all regarded as very important for public health epidemiologists. Epidemiologist competencies focused on the provision, interpretation and 'translation' of evidence to inform decision-making by other public health professionals. Considerable tension existed around some potential competency items, particularly in the areas of more advanced database and data-analytic skills., Interpretation: Empirical data can inform discussions of discipline-specific competencies as one input to decisions about competencies appropriate for epidemiologists in the public health workforce.

Background: Since its founding in 1970, Canada's International Development Research Centre (IDRC) has supported research by concerned Latin American researchers on environments and human health relationships. Framing of such relationships has changed through different periods., Methods: Participant observation, bibliographic searches, document review, and interviews with key IDRC staff., Findings: From the early years of multiple different projects, IDRC developed more focussed interest in tropical diseases, pesticides, agriculture and human health in the 1980s. The United Nations Conference on Sustainable Development in the early 1990s gave impetus to examination of links between ecosystems and human health or "EcoHealth". Projects in Latin America built on earlier work but extended it in methods (transdisciplinarity, community participation, gendered approach) and scope (broader land use and development paradigm issues tackled). A key IDRC-funded activity in Latin America was "EcoSalud", an Ecuadorian effort, which has worked with farming communities, agricultural researchers, health practitioners and local politicians to advance integrated pest management, better recognize and treat poisonings and improve pesticide-related policies. ONGOING CHALLENGES INCLUDE: mobilizing sufficient resources for the primary prevention focus of EcoHealth activities when primary care infrastructure remains stretched, promoting micro-level change in diverse communities and ecosystems, and addressing power structures at the global level that profoundly affect environmental change.

Objectives: To assess the impact of a workplace ergonomic program to reduce musculoskeletal burden among newspaper employees and to understand relationships among participation, risk factor changes and health status within an employee cohort., Methods: We conducted repeat cross-sectional surveys, with 1,003 employees from all major departments in 1996 and 813 in 2001, generating a cohort of 433 participants in both surveys. Elements of the ergonomic program included employee RSI (repetitive strain injury) training, pro-active assessment of workstations and workstation modifications, and encouragement of early treatment through on-site physiotherapy. Potential risk factors included biomechanical and work organizational aspects of office work. Health status measures included pain intensity and the Work-Disability of the Arm, Shoulder, and Hand (DASH). Repeat cross-sectional analyses incorporated modifications for shared variance. For the cohort, a theory of change informed path analyses using MPLUS., Results: Among respondents in 2001, 69% reported participation in RSI training and 56% had workstation assessments. Among those with pain, 57% had consulted a health practitioner, including the on-site physiotherapist. In repeat cross-sectional analyses, the proportion reporting moderate pain or worse, at least once per month or for longer than 1 week, declined from 20 to 16% (p=0.01). Among the cohort, pain intensity and work disability in 1996 were the strongest predictors of 2001 health status (both p<0.001). Stable or increased supervisor awareness and concern about RSI was associated with decreased pain in 2001(p<0.01). Participation in RSI training was associated with increases in decision latitude (p<0.05), which themselves were associated with decreased work disability in 2001 (p<0.05). Increased time mousing was associated with increases in work disability (p<0.05)., Conclusions: Implementation of a worksite ergonomics program was associated with a reduction in frequent and severe pain in the workforce. Changes in work disability were affected by multiple factors.

Objectives: We assessed predictors of work-related repetitive strain injuries using data from 4 waves of the Canadian National Population Health Survey., Methods: Participants were 2806 working adults who completed an abbreviated version of the Job Content Questionnaire in 1994-1995 and did not experience repetitive strain injuries prior to 2000-2001. Potential previous wave predictors of work-related repetitive strain injuries were modeled via multivariate logistic regression., Results: Female gender (odds ratio [OR] = 1.98; 95% confidence interval [CI]=1.24, 3.18), some college or university education (OR=1.98; 95% CI=1.06, 3.70), job insecurity (OR=1.76; 95% CI=1.07, 2.91), high physical exertion levels (OR = 2.00; 95% CI = 1.29, 3.12), and high levels of psychological demands (OR = 1.61; 95% CI = 1.02, 2.52) were all positively associated with work-related repetitive strain injuries, whereas working less than 30 hours per week exhibited a negative association with such injuries (OR=0.2; 95% CI=0.1, 0.7)., Conclusions: Modifiable job characteristics are important predictors of work-related repetitive strain injuries.

Background: Quality-of-work-life (QWL) includes broad aspects of the work environment that affect employee learning and health. Canadian health care organizations (HCOs) are being encouraged to monitor QWL, expanding existing occupational health surveillance capacities., Aim: To investigate the understanding, collection, diffusion and use of QWL indicators in Canadian HCOs., Methods: We obtained cooperation from six diverse public HCOs managing 41 sites. We reviewed documentation relevant to QWL and conducted 58 focus groups/team interviews with strategic, support and programme teams. Group interviews were taped, reviewed and analysed for themes using qualitative data techniques. Indicators were classified by purpose and HCO level., Results: QWL indicators, as such, were relatively new to most HCOs yet the data managed by human resource and occupational health and safety support teams were highly relevant to monitoring of employee well-being (119 of 209 mentioned indicators), e.g. sickness absence. Monitoring of working conditions (62/209) was also important, e.g. indicators of employee workload. Uncommon were indicators of biomechanical and psychosocial hazards at work, despite their being important causes of morbidity among HCO employees. Although imprecision in the definition of QWL indicators, limited links with other HCO performance measures and inadequate HCO resources for implementation were common, most HCOs cited ways in which QWL indicators had influenced planning and evaluation of prevention efforts., Conclusions: Increase in targeted HCO resources, inclusion of other QWL indicators and greater integration with HCO management systems could all improve HCO decision-makers' access to information relevant to employee health.

The practice of chlorine disinfection of drinking water to reduce microbial risks provides substantial benefits to public health. However, increasing concern around potential risks of cancer associated with exposure to chlorinated disinfection byproducts confuses this issue. This article examines the science agenda regarding chlorinated disinfection byproducts (CDBP) and cancer in Canada and the United States, focusing on the social construction of scientific knowledge claims and evidence. Data for this analysis were obtained from published documents as well as from in-depth interviews with epidemiologists and toxicologists centrally involved with the issue in both countries. Results of the analysis suggest that toxicological scientists want to close the door on the "chloroform issue" due to increasing evidence that chloroform is safe at low doses, because epidemiological scientists can no longer move forward the cancer science until significant improvements can be made in assessing human exposures, and because the scientific foci of research on DBP have shifted accordingly. Further, a distinction emerges in terms of how scientific uncertainties are interpreted when they cross-cut disciplines in the context of human health risk assessment. We suggest this tension reflects a balance of how uncertainty and authorities are managed in a mandated science-policy domain. Sufficient evidence was provided to keep the DBP issue on the regulatory agenda and to generate additional research, yet authorities and concomitant interpretations of uncertainty were contested. Such science generation and contestation inevitably influences complex risk assessment processes with respect to what water-related health risks are addressed and how.

Work stressors are increasingly recognized as potentially important determinants of mental health status. We examined such relationships using a structural equation modelling approach with data on adult, working Canadians who participated in the first wave of the National Population Health Survey (NPHS). Work stressors formed a composite construct with paths from psychological demands, decision latitude, work social support and job insecurity, each measured through a reduced version of the Job Content Questionnaire. Life stressors also formed a composite construct composed of chronic stressors and recent life events. Psychological distress was the outcome, mediated by the latent effect constructs of mastery and self-esteem. Work stressors had consistently positive total effects on distress (sum of standardized path coefficients from 0.004 to 0.153 across gender-occupation strata), with all of these effects mediated through reduced self-esteem and mastery (work stressors to these mediators: -0.188 to -0.413). Life stressors had larger positive total effects on distress (0.462 to 0.536), with the majority of these effects direct.

Objectives: To describe the prevalence of musculoskeletal problems in the Canadian working population and to determine cross sectional associations between such problems and work factors, particularly job strain and physical demand variables., Methods: The Canadian 1994 national population health survey (NPHS) sampled 4230 working men and 4043 working women (ages 18-64) who answered an abbreviated version of the job content questionnaire. Workers were classified into four strain categories: high, passive, active, and low. Outcomes were restricted activity due to musculoskeletal disorders and the diagnosis of a back problem (both yes or no). Survey weights were incorporated to allow for different probabilities of selection. Logistic regression analyses were carried out separately for women and men, controlling for sociodemographic factors., Results: Prevalence of chronic back problems diagnosed by a health practitioner was 14.5% among men and 12.5% among women. Men had a 6.6% prevalence of restricted activity due to musculoskeletal disorders, whereas the corresponding figure for women was 5.3%. Women, but not men, in high strain jobs were more likely to report both back problems (odds ratio (OR) 1.60, 95% confidence interval (95% CI) 1.14 to 2.28) and restricted activity (OR 1.98, 95% CI 1.16 to 3.48) compared with those in low strain jobs. High physical exertion was an independent predictor of back problems in both sexes. For both men and women, low social support at work and high job insecurity were independent predictors of restricted activity due to musculoskeletal disorders. Conversely, chronic back problems contributed to explanation of high job strain among women (OR 1.76, 95% CI 1.30 to 2.39) and high physical exertion among men (OR 1.39, 95% CI 1.09 to 1.77), whereas restricted activity due to musculoskeletal disorders contributed to explanation of high job insecurity in both sexes., Conclusions: Associations of interest between work stressors and musculoskeletal problems in this cross sectional study provide evidence for physical and psychosocial factors both affecting disability and being affected by disability in a working population.

This paper explores the associations, for working women and men, of high strain jobs with self-rated health in the 1994/95 Canadian National Population Health Survey (NPHS). NPHS data were obtained on men (n = 4230) and women (n = 4043), aged 18-64 who answered an abbreviated version oF the job content questionnaire (JCQ). Using the upper and lower tertiles of psychological demands and decision latitude as cut points we classified workers into high strain and other jobs. Self-rated health was the outcome. We used polytomous logistic regression analyses and controlled for potential personal and home confounders; two risk parameters were estimated: for the odds of reporting poor/fair and good health both vs. very good/excellent health. High strain work was reported by 11% of women and 9% of men. After adjusting for potential confounders, high job strain was consistently associated with worse self-rated health in both models for each gender.

At a metropolitan newspaper office in Canada with extensive video display terminal (VDT) use, researchers carried out a survey (n = 1,007, 84% response) to establish baseline prevalence of work-related musculoskeletal disorders (WMSDs) and to identify demographic, postural, task, and psychosocial factors associated with WMSD symptoms. One-fifth of the respondents reported moderate or worse upper limb pain recurring at least monthly or lasting more than a week over the previous year. Logistic regression showed that employees who faced frequent deadlines and high psychological demands (fast work pace and conflicting demands), had low skill discretion and social support, spent more time keyboarding, or who had their screen in a non-optimal position were more likely to report moderate to severe symptoms. Women reported significantly higher levels of symptoms than men.

Traditional epidemiological approaches based on biomedical models may be limited with respect to their response to "outbreaks of concern" among work-force or community populations. Three published Canadian "outbreaks" were reviewed in this study. In all three instances, research was initiated because lay persons were concerned about either nonspecific symptoms or hazardous exposures, and individuals publicly called for a response. Epidemiologic analyses were inconclusive as to the reasons for the outbreaks, and they contributed little toward the resolution of concerns. There is a need for a fuller recognition of the role of social context and of the action-oriented nature of such research. The elucidation of multifactorial and culturally mediated causation, as well as the development of remedial actions, require a rethinking of research methods. We specifically call for (a) an expansion of the disciplinary base of research teams to include social scientists, and (b) the adoption of combined qualitative and quantitative research approaches.