Methods
We artificially induced skew in 10 healthy participants aged from 26 to 66 (mean 39.0 y +/-11 y, 3 males, 7 females) using FP on the left eye: we then undertook the VOG and the APCT measurements. The refractory value of the FP ranged from 1-10 prism diopters (PD) (1 PD (0.57°), 2 PD (1.14°), 4 PD(2.28°), 6 PD (3.42°), 8 PD(4.56°) and 10 PD (5.70°)): these were randomly applied (random order derangement). The examiner of the APCT was blinded regarding the FP used, but could choose between different prism strengths ranging from 1 to 10 PD. We compared VOG results to the actual value of the FPs and correlated the obtained results with the current gold standard of the ACPT. We excluded all subjects 1) having previously experienced dizziness, 2) suffering from a previous neurological disorder (including cognitive impairment), 3) suffering from poor vision, 4) double vision, 5) strabismus and 6) any pregnant subjects.