The influences of age, gender and geometric pattern of visual image on the verticality perception: A subjective visual vertical (SVV) study among Malaysian adults

Objectives Subjective visual vertical (SVV) is a simple, quick and reliable test for measuring utricular function. The literature on the effects of fundamental demographic variables such as age and gender on SVV is inconclusive and should be supported by research with larger samples. The aim of the present study was to determine the influences of age, gender and geometric pattern of visual image on SVV among healthy adults. Study Design This study employed a repeated measures design. Settings Otorhinolaryngology Clinic, Hospital Universiti Sains Malaysia, Malaysia. Participants Eligible Malaysian adults (N = 187, aged 21-75 years) were recruited and categorised into young (N = 60), middle-aged (N = 66) and older (N = 61) groups. Most of them were Malay, and 51.3% were men. Main Outcome Measures Subjective visual vertical angles (in degrees) were determined from each participant in a static upright condition using a computerised SVV device. They were asked to indicate their verticality perception for three types of visual images (solid line, dotted line and arrow pattern). Results Three-way mixed ANOVA revealed insignificant influences of age and gender on SVV results (P > 0.05). In contrast, mean SVV angles were significantly higher for the arrow pattern than for other visual images (P = 0.004). Conclusion While the insignificant influences of age and gender on static SVV are further ascertained with larger samples, the perception of verticality is less accurate when aligning a more geometrically complex visual image (ie, arrow pattern). Further SVV research on vestibular-disordered patients is beneficial, particularly to verify the normative data obtained with this complex visual image.