Relationships among optimism, pessimism, and posttraumatic growth in the US and Japan: Focusing on varying patterns of perceived stressfulness

Posttraumatic growth (PTG), perceived positive changes resulting from highly stressful life experiences, can vary as a function of personality characteristics. Past research shows mixed findings on the relationship between PTG and optimism. The current study examined how the relationships among optimism, pessimism, and PTG differ across varying patterns of stressfulness in two nations. In a cross-sectional survey, American (n = 464) and Japanese (n = 282) undergraduates identified a highly stressful event they experienced within the past five years and completed a series of questionnaires. Three meaningful clusters (i.e., Recovery, Chronic Stress, and Low Stress) emerged based on retrospective and current reports of stressfulness. Results from multi-group analyses demonstrated that optimism predicted higher PTG among both Americans and Japanese in the Chronic Stress group, but solely among Americans in the Recovery group. Pessimism did not have consistently significant associations across PTG domains for Americans or Japanese in any cluster. Findings suggest that PTG and Recovery are distinct processes; people can experience PTG even in the absence of a Recovery pattern. Furthermore, optimism appears to be a more consistent predictor for Americans than for Japanese, and pessimism does not appear to be influential for PTG in either nation.