The results of the present study co

The results of the present study contribute to research on stress, optimism, and personality.
Although many studies have viewed optimism as a stable or unchangeable trait, our findings add
to a growing body of research indicating that optimism can be modified (Dewberry & Richardson,
1990; Peterson, 2000; Robinson-Whelen et al., 1997; Schulz et al., 1988). The effects detected in
this study were generally modest, but they do not detract from the conceptual assertion that
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optimism can vary over time and that stress can predict those changes. Furthermore, the findings
of the present study that a significant minority of women reported change in optimism at the
individual level highlights the importance of including individual-level analyses when examining
the stability or change of optimism. Future longitudinal studies of optimism should avoid simply
measuring initial levels of optimism and, instead, assess optimism at multiple time points to determine
whether change has occurred at both individual and group levels.