Childhood trauma including severe physical, sexual or emotional abuse is believed to be the chief trigger of dissociative disorders. Other stressors that can trigger these conditions include traumatic events such as combat, natural disasters, kidnapping, torture, head injury and invasive medical procedures.

Children experiencing severe trauma may develop dissociative disorders as a means of coping. Children under the age of 4 have a greater ability than adults to step outside themselves and observe trauma in a third-person fashion. Children who dissociate in this way as a means of coping may continue to use the practice as adults whenever they are confronted with highly stressful situations.

Although many dissociative disorders are not diagnosed until adulthood, instances in which a person develops dissociative disorder as an adult are rare. The exceptions to this rule are dissociative fugue, and dissociative amnesia due to head trauma, most cases of which originate in adults.

Dissociative disorders are more often diagnosed in women than in men. Clinicians with experience diagnosing and treating dissociative disorders believe that they are frequently misdiagnosed as other psychiatric disorders. The average patient with a severe dissociative disorder has been treated in the psychiatric system for about eight years before the diagnosis is identified.