to investigate the role of general life stress on vulnerablity to the common cold.
- completed questionnaire on number of stressful life events they had experienced in the previous year.
- Rated their degree of stress
- rated level of negative emotions
- three scores combined into a stress index score
participants exposed to common cold
- 82% became infected.
- After 7 days, number who had developed clinical colds was recorded.
- chance of catching a cold significantly correlated with stress index score
life stress and negative emotions reduce the effectiveness of the immune system, leaving people less able to resist viral infections.
- supported by evans and edginton (1991) who found probabilty of developin a cold significantly correlated with negative events from proceeding days.
- measured health outcomes showing a relationship between stress and illness, whereas, some studies just measure immune function.
- no direct manipulation of the independant variable so cause and effect relationship cant be established.
- By combining the three measures, we cant tell which element of the stress index is most important in making us more vulnerable to viruses.