Information was collected among six participating medial centers on frequency of performance and the percentage of abnormality of 30 tests performed on patients with complaints suggesting transient ischemic attacks (TIAs). A number of these were commonly performed and commonly exhibited abnormalities. Although the diagnosis of TIA is made by history and physical examination, these tests were of value in aiding the physician to determine possible causes of TIA, to detect risk factors of associated conditions, to rule out alternative diagnoses, and to assess the patient's ability to tolerate different types of therapy.