Which is NOT a criterion for PTSD eligibility?

Serving in a combat zone is not a strict criterion for eligibility for Post-Traumatic Stress Disorder (PTSD). While serving in a combat zone can certainly contribute to experiences that may lead to PTSD, individuals may develop PTSD from a variety of stressors encountered during their military service, not exclusively those related to combat situations.

In contrast, the other criteria focus on specific requirements that must be met for establishing a valid claim for PTSD. Medical evidence establishing a diagnosis is critical because it provides the clinical basis for the claim. Credible supporting evidence of an in-service stressor is essential because it connects the veteran's current symptoms to a specific event or series of events that occurred during military service. Finally, establishing a nexus through medical evidence is crucial to demonstrate the link between the stressor and the current psychological issues the individual faces.