Variability in the stability of personality traits across a single combat deployment.

This study assessed changes in measures of personality traits across a 12-month combat deployment in a sample of conventional US Army soldiers. Results revealed Impulsive Sensation-Seeking (ImpSS) and Sociability (Sy) decreased significantly, whereas Neuroticism-Anxiety (N-Anx) increased. Changes in ImpSS scores were mainly attributed to age, but were inversely related to increases in traumatic stress symptoms. Combat exposure, concussion, age, education, and changes in traumatic stress scores all independently contributed to changes in N-Anx scores. Changes in Sy were not associated with any of the data available from pre-deployment or deployment measures. Changes in Aggression-hostility (Agg-Hos) and Activity (Act) across the deployment were not significant. The findings suggest significant variability in the stability of personality traits when exposed to combat stress and injury while deployed, which may be influenced by factors such as age and education.