Self-rated health and perceived illness vulnerability as mediators of exercise and office visits

The purpose of this study was to test a model to examine the mediational role of perceived illness vulnerability and self-rated health in predicting exercise and office visits, and the degree to which age may influence these effects. The possible influence of perceived controllability in moderating these effects was also explored. The exogenous predictors were perceived symptoms, depressive symptoms, and perceived friend support. The subjects were 3025 individuals from 24 to 74 responding to the 1995 National Survey of Midlife Development in the United States. The study used multiple group analysis on Mplus to investigate age group differences in the relations among these variables among young, middle, and older adults and among individuals with high and low controllability. The study were consistent with causal relations such that, given the models in the present study, self-rated health acted as a mediator in predicting exercise and office visits, and perceived illness vulnerability acted as mediator in predicting exercise, but not in predicting office visits. Age did not moderate the relationships among the constructs. In the model with office visits as the dependent variable, perceived controllability moderated the relationship between depressive symptoms and self-rated health. Selfrated health mediated the effect of depressive symptoms on effects of office visits only in low controllability. Implications for interventions are discussed.