to show descriptive statistics for all dependent measures by test conditions These measures include angle of veering from the center, step length, distance the subject walked before veering, velocity of walking, and the number of steps taken.
Mean angle of veering (deg) and mean distance walked before veering (m), (standard deviations and ranges in parentheses) (N = normal, UW = unilateral weakness; EO – eyes opened, EC = eyes closed)
Mean velocity (standard deviations and ranges in parentheses) and median number of steps (ranges in parentheses) (N = normal, UW = unilateral weakness; EO – eyes opened, EC = eyes closed; Vel= velocity)
With eyes closed, normals veered significantly less than BPPV (p=0.048) and unilateral weakness patients (p=0.0006). When adjusted for age and sex, normals still veered significantly less than unilateral weakness subjects (p< 0.005). The difference between normals and BPPV subjects was no longer significant (p=0.1) and BPPV subjects did not differ significantly from unilateral weakness subjects (p=0.5). Angle of veering was related to speed, even when adjusted for age and sex (p=0.02). In general with groups collapsed subjects veered less at the medium speed (5.2°) than the slow (7.2°) or fast speeds (7.1°). See .
With eyes closed normals walked farther before veering (5.3 m) than unilateral weakness patients (4.2 m); this trend remained significant after adjustment for age and sex (was significant for age (F=20.7, p<0.0001), sex (F=8.45, p=0.005) and group (F=3.7, p=0.3). When adjusted for age and sex the normal and unilateral weakness groups differed significantly (p<0.03), indicating that normals walked further than patients before veering but the BPPV group did not differ significantly from either group. See .
The distance walked before veering might have been a reflection of differences in step length. The diagnostic groups did not differ significantly by step length. Step length was significantly greater at the medium speed compared to the slow (p= 002) or fast (p=0.56) speeds. Step length at slow and fast speeds did not differ significantly. Not surprisingly, step length was larger with eyes open than with eyes closed (p<0.0001). See .
Mean step length (m), (standard deviations and ranges in parentheses) (N = normal, UW = unilateral weakness; EO – eyes opened, EC = eyes closed; Vel= velocity)
In general within each group and visual condition velocity of walking increased significantly with increasing speed (p<0.0001). Walking velocity was significantly higher with eyes open than eyes closed within each group and speed condition (p<0.001). These relationships remained significant after controlling for age and sex. See . With the groups collapsed velocity decreased weakly with increased age at medium (Eyes open, r=−0.3, p=0.009; Eyes closed, r=−0.3, p=0.02) and fast (Eyes open, −0.2, p=0.07, Eyes closed, r=−0.3, p<0.3) walking speeds. For normal subjects the relationship between velocity and age was nonsignificant. For the two patient groups the relationship between velocity and age was significant but only moderate, for the BPPV group at the fast speed with eyes closed, r= −0.5, p<0.03; for the unilateral weakness group at the medium speed with eyes open, r=−0.5, p<0.03. No other significant correlations between age and velocity were found.
The number of steps did not differ significantly across the three study groups when adjusted for age and sex. Subjects took significantly fewer steps with eyes open than eyes closed; regardless of group (p=0.0008). In general the number of steps increased with increasing speed (p=0.001). See .