Exams and Tests

The diagnosis of Tourette's syndrome is based on clinical information and a physical examination.

At the present time there is no test that will confirm the diagnosis. However, the physician might recommend some tests in certain cases just to rule out other possible diseases.

The Diagnostic and Statistical Manual for Mental Disorders, 4th edition (DSM-IV), a common source of reference for diagnostic purposes, established as a criteria for the diagnosis of Tourette's syndrome:

• the presence of both multiple motor tics and one or more phonic tics that might be present at some time, although not necessarily concurrently.
  
  
• The tics must occur many times a day (usually in bouts) nearly every day or intermittently over more than a year, during which time there must not have been a tic-free period of more that three consecutive months. The onset occurs before the age of 18 years. Also there may not be other explanation for the tics.

When the patient meets these criteria it is usually not necessary to perform other tests.

There are some scales, such as the Yale Global Tic Severity Scale (YGTSS), that may be helpful to determine the level of impairment and to evaluate treatment options.

Neuropsychological testing may be indicated only for children with school problems, otherwise this is not useful.