Clinical Significance of Psychoneuroimmunology: Prediction of Cancer Outcomes
Sandra M. Levy University of Pittsburgh School of Medicine Pittsburgh Cancer Institute
Dawn C. Roberts University of Iowa
Most psychological studies that assess immunological components implicitly use these measures in one of two ways. In the first, an immunological measure may be used as an indicator of a psychological process. The primary goal of these studies is to draw inferences about psychological constructs or theories. In the second, an immunological measure may be used to explain the relation between a psychological process and a physical health outome. The goal of this second class of studies is to specify the mechanism of disease initiation or progression.
Distinction of these two classes is important because it guides research questions and methodologies, and directs overall progress within the field of psychoneuroimmunology. For instance, a common research strategy within psychoneuroimmunology is to establish covariation between psychological and immunological measures. However, establishing covariation does not necessarily advance the goal of the first class of studies ( Cacioppo & Tassinary, 1990) nor does it automatically achieve the purposes of the second class of studies. The aim of the former additionally requires the delineation of immunological (and possibly other physiological system) patterns in the search for invariant relationships with psychological processes ( Cacioppo & Tassinary, 1990). Likewise, the aim of the latter group of studies additionally requires demonstration of clinical as well as statistical significance of psychoimmunological covariation by predicting health outcomes. It is important, however, to note that these aims are not mutually exclusive, and indeed, investigations that strive to meet both goals likely will make stronger advances toward knowledge in the field.
It is the purpose of this chapter to discuss the use of immunological