Worldwide there is much variation between continents with South America having the highest prevalence (18%), closely followed by Oceania (16.3%). The continent found to have least sufferers was Africa (10.9%).Multiple studies have provided evidence that there is no gender difference. However, a study by Kathmandu University reports that post eruptive breakdown occurs more frequently in boys than it does in girls. A different study found that children under the age of 10 are more highly affected by the disease (15.1%) compared to older children (12.1%). == References ==
A history of frequent illnesses may also contribute to the development of this disorder. In some cases, individuals with factitious disorder are accustomed to actually being sick, and thus return to their previous state to recapture what they once considered the "norm". Another cause is a history of close contact with someone (a friend or family member) who had a severe or chronic condition. The patients found themselves subconsciously envious of the attention said relation received, and felt that they themselves faded into the background. Thus medical attention makes them feel glamorous and special. Diagnosis
Criteria for diagnosis include intentionally fabricating to produce physical or psychological signs or symptoms and the absence of any other mental disorder. Motivation for their behavior must be to assume the "sick" role, and they do not act sick for personal gain as in the case of malingering sentiments. When the individual applies this pretended sickness to a dependent, for example, a child, it is often referred to as "factitious disorder by proxy".The DSM-5 differentiates among two types:

Factitious disorder imposed on self (Munchausen syndrome)
Factitious disorder imposed on another (Munchausen syndrome by proxy), defined as: When an individual falsifies illness in another, whether that be a child, pet, or older adult. Factitious disorder imposed on self
Factitious disorder imposed on self, previously called Munchausen syndrome, or factitious disorder with predominantly physical signs and symptoms, has specified symptoms. Factitious disorder symptoms may seem exaggerated; individuals undergo major surgery repeatedly, and they "hospital jump" or migrate to avoid detection.