Evaluating a Tool for Assessment of Adjustment Disorder in the U.S. Military: The Adjustment Disorder–New Module 20 for Military (ADNM-20-MIL)

OBJECTIVES: Adjustment disorder (AjD) is a highly prevalent diagnosis in the U.S. military. Psychometric evaluation of the AjD assessment tool, the Adjustment Disorder New Module-Military (ADNM-20-MIL), improves the accuracy of AjD assessment for military service members.

METHODS: This study investigated the internal reliability, convergent, and divergent validity of the ADNM-20-MIL as well as its factor structure. U.S. active duty service members (N = 149) with and without a recent AjD diagnosis completed the ADNM-20-MIL, Depression Anxiety Stress Scales 21 (DASS-21), Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5), and General Well-Being Schedule (GWB).

RESULTS: ADNM-20-MIL scores were significantly worse in the AjD-positive group; there were no AjD severity differences by sex, military rank, or past recent deployment status. The ADNM-20-MIL demonstrated robust internal reliability (Cronbach's α = 0.96, 95% CI [0.95-0.97]). It had strong positive associations with with the PCL-5 (rs (145) = 0.81, p < 0.001) and the DASS-21 (rs (146) = 0.83, p < 0.001), indicating convergent validity; and moderately negative associations with the GWB subdomains that reflect positive health (rs ranging from -0.5 to -0.63), p < 0.001, indicating divergent validity. Confirmatory Factor Analysis indicated a unidimensional structure for AjD symptoms.

CONCLUSIONS: Longitudinal studies are needed to evaluate the effectiveness of the ADNM-20-MIL in assessing the trajectory of AjD in the military.