A wastebasket diagnosis is an imaginary or vague diagnosis put on a patient's chart for non-medical reasons. Most ethically, it is used to reassure a patient who may be suffering from vague or psychosomatic symptoms. Less ethical doctors will use the diagnosis to ensure the patient receives insurance coverage for a variety of medical procedures or tests. Wastebasket diagnoses are also used to reassure patients who will most likely improve on their own.
The term is often used to describe controversial diseases such as Gulf War syndrome, which, ironically, now have clear diagnostic criteria. A doctor will also treat a diagnosis from an alternative medicine practitioner as a wastebasket diagnosis. Of the diseases with clear diagnostic criteria, some are still used as wastebasket diagnoses such as fibromyalgia (for any type of chronic pain), chronic fatigue syndrome, acid reflux and bronchitis.
House is not above using wastebasket diagnoses and invented Ortoli syndrome in Brave Heart to reassure a person that he did not have a genetic disease after all his tests were negative.