has been found, although the most consistent findings relate to the differential vulner -
ability hypothesis. However, Stronks et al. (1998) have suggested that the importance
of the differential exposure hypothesis has been underestimated.
Cohen, Doyle and Baum (2006) investigated the link between SES and a number
of stress hormones. After controlling for race, age, gender and body mass index, the
results showed that lower SES was associated with higher levels of cortisol, adrenaline
and noradrenaline, mirroring Sapolsky’s work with baboons. More impressively,
Cohen et al. (2006) also showed that the effects of SES on these stress hormones were
mediated via smoking status, not eating breakfast and having a less diverse social
network. These findings emphasize the importance of psychological, biological and
behavioural factors in understanding the effects of SES on health. They suggest that
health behaviours and social resources, typifying lower SES, explain why those in lower
SES positions suffer greater stress-related illness.
WORK STRESS AND OCCUPATIONAL HEALTH PSYCHOLOGY
Investigating and reducing work stress has become a major focus of a newly established
field of psychology known as occupational health psychology. The US National
Institute of Occupational Safety and Health (NIOSH) states that ‘Occupational Health
Psychology concerns the application of psychology to improving the quality of
working life and to protecting and promoting the safety, health and well-being of
workers’ (NIOSH, 2010). The emphasis here is on reducing occupational stress, injuries
and illness and there are now a number of postgraduate courses, which are concerned
with psychosocial and organizational issues relevant to occupational health and safety
(see Chapter 11). The research literature on stress is vast but some key models of work
stress can be identified.
Theories and models of work stress
A number of writers have produced useful frameworks and models summarizing key
variables that might cause stress for individuals at work (Warr, 1987; Cooper, Sloan
and Williams, 1988). For example, Warr (1987) listed nine key stressors, which are
like vitamins, in that a certain amount is essential for good mental health. Thus, to
minimize stress, a job needs to have (1) appropriate levels of personal control over
activities and events; and (2) the right amount of opportunity to use existing skills and
develop new skills. The job also needs to provide (3) opportunities to pursue goals or
meet demands; and have the right amount of (4) variety; (5) clarity; and (6) opportunity
for interpersonal contact. Like some vitamins (e.g. vitamins A and D), either too much
or too little of these variables may be bad for well-being. However, the final three
factors (like vitamins C and E) are only thought to be stressful if there is a shortage.
These are (7) money; (8) physical security (e.g. job security or working conditions);
and holding a (9) valued social position. This framework simply focuses on external
environmental stressors. However, as we noted in Chapter 3, people vary in their
perceptions of stressors and in their ability to cope, so what is a reasonable demand
for one person will overload another.
STRESS AND HEALTH IN CONTEXT 71