Adaptation to military operational stress and trauma is an unfolding dynamic, impacted by a complex web of biological, psychological, social, and service-related risk and resilience factors. Because of this, there is no single course of adjustment to combat stress over time, but rather, a number of potential outcome trajectories. Though contemporary models of stress, trauma, and illness posit complex, multidimensional, and multivariate networks of factors that may contribute to the development of maladaptive outcomes, the predictors of different trajectories of response to combat-related trauma remain unknown. It is also unclear who best responds to treatments while they are still in the military.

In order to better understand such complexities, the primary aim of the Assessment Core is to evaluate the impact of a central set of predictor variables (including dispositional, deployment, and post-deployment factors) on the high-probability mental health-related outcomes resulting from service in Operation Iraqi Freedom/Operation Enduring Freedom. Our variable selection has been guided by prior cross-sectional research and by contemporary stress and illness models. Because every study in the Consortium has a longitudinal framework and will be employing the same measures, the Assessment Core will ultimately be able to compare standardized outcomes across time, as well as predictors of those outcomes, by collapsing data across studies.

The Assessment Core has four specific objectives:

• to create uniformity of instrumentation, employing measures with sound psychometric properties;
• to ensure sufficient construct coverage of outcome and predictor variables by creating a list of required and recommended measures to be used by each STRONG STAR study;
• to work with the Data Core to create and manage the multi-study dataset; and
• to test causal models of risk and resilience variables that predict different trajectories of adaptation to war-zone trauma, paying special attention to dispositional, deployment-related, and treatment-type moderators.