Differential Diagnoses:

If the head trauma results in dementia, postconcussional disorder should not be diagnosed and mild neurocognitive disorder should be considered.

Somatization Disorder and Undifferentiated Somatoform Disorder many also manifest similar symptoms.

Factitious Disorder and Malingering must also be distinguished from the postconcusional disorder diagnosis.

Affective Disorders, such as depression, must also be ruled out for a diagnosis.

Diagnosis of postconcussional disorder is rather complicated because of several factors: 1) no external evidence of head trauma, 2) 38% of people who suffer a head injury have no evidence of an injury in MRI, CT, and PET scans, and 3) the criteria is based on subjective indicators of impairments.  These factors contribute to the ongoing research to help distinguish a accurate diagnosis of postconcussional disorder.