social capital are associated with the improved ability of communities to exercise informal social control over deviant behaviors (such as smoking and drinking by minors), as well as to undertake collective action for mutual benefit (e.g., passage of local ordinances to restrict smoking in public places). Social capital and social cohesion are therefore potentially important characteristics of the “social and cultural environment” that ultimately influence patterns of health achievement.
The psychosocial work environment—particularly exposure to job stress—has been linked to the onset of several conditions, including cardiovascular disease, musculoskeletal disorders, and mental illness (Marmot and Wilkinson, 2006). Two models of job stress have received particular attention in the literature: the job demand-control model (Karasek and Theorell, 1990) and the effort-reward imbalance model (Siegrist et al., 1986). The demand-control model posits that it is the combination of high psychological demands and low level of control (low decision authority and skill utilization) that leads to high physiological strain among workers and hence to the onset of disease (such as hypertension and cardiovascular disease) (Marmot and Wilkinson, 2006). A pencil-and-paper questionnaire to measure job demands and job control has been developed and validated for use in population-based studies (and can be accessed at www.uml.edu/Dept/WE/research/jcq).
In contrast to the demand-control model of job stress, the effort-reward imbalance model developed by Siegrist maintains that working conditions produce adverse health outcomes when the costs associated with the job (e.g., high level of effort) exceed its rewards (money, esteem, and career opportunities) (Siegrist et al, 1986). As with the demand-control model, a self-administered questionnaire has been developed and validated. Both the demand-control model and the effort-reward imbalance model have been shown to predict the incidence of cardiovascular disease and other health outcomes in longitudinal observational studies (Marmot and Wilkinson, 2006).
The relationship between job stress and health is likely to be reciprocal, however. For example, the onset of subtle illness symptoms may result in the worker switching to a less demanding job. In theory, this issue could be addressed in longitudinal studies through careful and repeated assessments of workers’ health symptoms over time. On the other hand, other problems, such as omitted variable bias, can present formidable challenges to causal inference in this field. For example, some individuals may “select into” certain occupations based on temperament, personality, and innate “hardiness;” while others may “select out” of stressful jobs for the same