| dc.description | One of Freud's most important contributions to psychology is the concept of defense mechanisms. Despite the importance of this concept, however, there are a number of theoretical and empirical difficulties that have hampered the investigation of defenses. I present two studies relating to the empirical investigation of defenses and demonstrate how psychodynamic constructs can be reliably and validly assessed. In study one, I use the Defense-Q (Davidson & MacGregor, 1996; MacGregor & Davidson, 1998) to empirically test the cross-sectional relation between adaptive defense use and resting blood pressure. Using a population-based sample stratified on age and gender, I test if adaptive defense use has a larger impact on resting blood pressure in older compared to younger persons. Results suggest that adaptive defense use may play a protective role in women but not in men in terms of the development of high blood pressure in later life. In study two, I again use the Defense-Q to empirically test the prospective relation between adaptive defense use and physician health care costs. Using the same population-based sample as in study one, I test if adaptive defense use is related to lower physician health care costs over a three-month period. Results suggest that adaptive defense use is related to decreased physician health care costs even when controlling for medical and psychiatric diagnoses. Results from these two studies suggest that the Defense-Q is both a reliable and valid instrument to assess defenses and that defense use is related to blood pressure and health care costs in theoretically meaningful ways. These results demonstrate that psychodynamic constructs can be empirically investigated and do contribute to our understanding of personality and health. | en_US |
