A total of 28 participants were randomly divided into two groups of 14, and participated in a prospective study in which each participant was tested with a standard Dix-Hallpike (S-DH) as well as a loaded Dix-Hallpike test (L-DH).
The L-DH positioning involved flexing the cervical spine by 30 degrees and rotated to the testing side, held in this position for 30 seconds before completing the remainder of the Dix-Hallpike test (starting in sitting, head rotated to side being tested, then assisted into full reclined position with cervical extension of 20 degrees).
Group 1 underwent the S-DH three times, and then the L-DH three times. Group 2 underwent the L-DH three times then the S-DH. Nystagmus was assessed for duration and latency of onset with each test. Symptom severity was recorded after each test as well.