Caricatures of optimists and pessimists are deeply embedded in our culture. Optimists are depicted as Pollyannaish, always expecting good things to happen, whereas pessimists are gloomier and always expect the worst. Do these differences in one’s orientation to life make any difference in terms of what happens to people? It turns out that how you view the future is in fact strongly associated with what happens to you. Decades of research have demonstrated that optimism is beneficially associated with many aspects of life, including physical health. Optimists have lower blood pressure and cholesterol levels, and are less likely to be overweight. Optimists are less likely to experience complications after surgery, and have healthier babies when they give birth. They are also less likely to develop diseases, such coronary heart disease and stroke, and are less likely to die from these diseases.

Although the benefits of optimism have been well-established, how best to conceptualize optimism has proven more difficult. Originally, optimism was thought of as a single dimension, ranging from highly optimistic on one end to highly pessimistic on the other. According to this view, if someone becomes less optimistic, the person must necessarily become more pessimistic. Most research to date has assumed this bipolar relationship between optimism and pessimism. However, very early on researchers began to challenge this view, suggesting that optimism and pessimism might be better conceptualized as two distinct constructs: one reflecting the affirmation versus disavowal of optimism and one reflecting the affirmation versus disavowal of pessimism. According to this view, someone who becomes less optimistic does not automatically have to become more pessimistic. Stated somewhat differently, expecting outcomes to be less good is not quite the same thing as expecting outcomes to be bad. They may still be good, just less so.

Researchers have attempted to resolve this question with statistical analyses of popular scales used to measure optimism. Although these analyses suggest that optimism and pessimism are somewhat distinct empirically, researchers have yet to agree on whether this distinction is meaningful or merely an artifact of how people respond to personality questionnaires. It is important to note, however, that statistical analyses are not the only way to determine if optimism and pessimism are meaningfully distinct. Another way to test this idea is to examine if optimism and pessimism have different correlates. For example, if pessimism predicted better health, while optimistic did not, it would suggest that the distinction between optimism and pessimism is useful. The present project seeks to re-analyze data contained in the existing optimism literature by conducting a meta-analysis of the research findings. The meta-analysis would make it possible to examine if optimism and pessimism have differential associations with physical health. If different associations emerge, clinicians would be in a better position to know which interventions to employ to promote better physical health outcomes. At present, it is unclear whether interventions are best directed toward promoting optimism, reducing pessimism, or targeting both.