Development of a psychometric measure of physical post traumatic growth in prostate cancer and evaluation of its role in predicting psychological adjustment

Abstract

Post traumatic growth (PTG) can be defined as positive change following a traumatic event (Tedeschi & Calhoun, 1995). The current conceptualisation of PTG encompasses five main dimensions: perceived changes in self; developing closer relationships; changing life philosophy/increased existential awareness; changed priorities and enhanced spiritual beliefs. However, there is no dimension which accounts for the distinct effect of a physical trauma on PTG. The purpose of the present research was to develop a psychometric measure that acknowledges the role that physical trauma and the body have in post traumatic growth and, in so doing, give a more comprehensive picture of post traumatic reactions. Men with prostate cancer were chosen given that previous research focuses on breast cancer survivors. This sample allowed investigation into the extent to which older men may experience 'physical post traumatic growth' (i.e., how physical trauma uniquely impacts growth). Qualitative interviews were conducted and analysed using thematic analysis. This resulted in four themes emerging, three of which related to the general prostate cancer survivorship experience (i.e., Resilience, Secrecy vs. Support and Acceptance), while one theme related to physical post traumatic growth (i.e., New Awareness). The theme 'New Awareness' informed the generation of items for the measure of physical post traumatic growth. Exploratory and confirmatory factor analyses revealed two factors of physical post traumatic growth, namely, 'Health Autonomy' and 'Health Awareness'. Reliability analyses and tests of validity were subsequently conducted. Internal reliability was excellent (.90, 95%CI = .88 - .92 ), while construct validity was supported with significant correlations observed between physical post traumatic growth and mindfulness (r=0.20, p < .01) and post traumatic growth (r=0.42, p < .001), no significant correlation was observed between physical post traumatic growth and body awareness. These findings offer further support for the psychometric soundness of the Physical Post Traumatic Growth Inventory (P-PTGI). The P-PTGI was then used to evaluate the role of physical post traumatic growth in predicting adjustment using structural equation modelling (SEM). Physical post traumatic growth predicted lower distress and improvement of quality of life, whereas conversely, the traditional post traumatic growth mesasure was linked with poor adjustment. The relationship between resilience and adjustment was fully mediated by physical post traumatic growth and traditional post traumatic growth. Furthermore, mindfulness was found to moderate the relationship between physical post traumatic growth, post traumatic growth and quality of life. In conclusion, the studies provide support for a new dimension of post traumatic growth following physical trauma and suggest the inclusion of physical trauma in future theoretical frameworks. Moreover, the hypothesised model has provided insight into the relationships between resilience, mindfulness, post traumatic growth and adjustment. This research also provides a valuable tool with good psychometric properties to measure physical post traumatic growth.