1. Patient convinced of chronic parasite infestation.
2. Primary patient illness focus must be either on dermal sensations or on "never-before-seen" material thought to be extruded from his or her body, even if this was not the most debilitating symptom or sign. The material must have been described as "fibers", "fiber-like", or "filaments".
3. Chronic pruritis (itching) must have been present for at least six months.
4. The patient must have at least two chronic, unhealed skin lesions recorded by a clinician, regardless of whether excoriation was suspected.
5. Prior diagnosis of Delusions of Parasitosis or bipolar illness would not exclude the patient as a candidate.
6. Patients experiencing delusional states common in withdrawal from drugs such as opiates and patients in organic brain states, were excluded.
7. The illness must have had a life-altering effect on the patient.
8. The patient must be an adult and had experiencing symptoms for more than six months.
9. A healthy pre-morbid period in the patient's life was acceptable.