Positive-Expectancy Factors on Long-Term Posttraumatic Stress Disorder Symptoms: A Prospective 2-Year Follow-Up Investigation Among Military Veterans

Military personnel are trained throughout their career for wartime, yet the expectation and the valence associated with being in combat differs quite extensively. Despite factors that could influence military personnel's perception of being exposed to combat, happenstance in combat theaters frequently results in experiencing combat even for those who would not necessarily expect to. Although the importance of expectations within the context of trauma has been evidenced in multiple contexts, combat expectancy has never been examined as having an influence in the trauma-posttraumatic stress disorder (PTSD) relationship. Based on stress-related theories that suggest expecting and valuing an event would act as a buffering agent, we introduce the concept of "positive-expectancy factors" (expectations of event, valence of the expected event) and argue that expectations and valence of events moderate the relationship between job demands (trauma exposure) and distress following combat (PTSD). Rooted in job resource demand, we test our hypothesis on a sample of Norwegian military personnel (N = 396) over four time points pre- to postdeployment to Afghanistan. Results support our hypothesis and reveal a buffering positive-expectancy interaction such that when experienced together, met expectations of an event (combat) and high event valence decrease PTSD. However, met expectations of combat, nor valence of combat by themselves, decrease PTSD. Results showed that military personnel who did not expect, nor hold valence for combat, were most at risk for PTSD if combat was experienced. We further discuss implications for high-risk occupations in military and civilian contexts.