Background:This study aims to delineate the characteristic features of adjustment disorder (AjD) from those of posttraumatic stress disorder (PTSD) and assess the discriminant validity of Diagnostic and statistical manual of mental disorders (DSM)-5 PTSD measures by comparing self-reported data from an outpatient cohort.

Methods:The study participants included psychiatric outpatients at a university-affiliated hospital in South Korea.Psychological assessments comprised the Post-Traumatic Stress Disorder Checklist for DSM-5, the National Stressful Events Survey-PTSD Short Scale, the Beck Depression Inventory-II, the Beck Anxiety Inventory, the Insomnia Severity Index, and the Short Form-8 Health Survey.

Results:A total of 149 responses (51 participants with AjD and 98 with PTSD) were analyzed. It was observed that workplace conflict was the most common stressor among AjD patients (29%), while traffic accidents were the primary trauma source for PTSD patients (39%). Individuals with AjD reported significantly lower levels of PTSD, depression, anxiety, and insomnia symptoms, along with a higher quality of life. After controlling for educational level as a covariate, the differences in PTSD and depressive symptoms remained significant.

Conclusion:The findings of this study support the discriminant validity of DSM-5 PTSD measures for AjD and reinforce the notion that that AjD represents a milder form within the stress response spectrum.