Mobile phone app Vs bucket test as a subjective visual vertical test: a validation study.

Area of Science:

• Neuroscience
• Vestibular System Research
• Clinical Assessment Tools

Background:

• The subjective visual vertical (SVV) assesses perception of gravitational vertical, crucial for balance.
• A tilt in SVV suggests vestibular imbalance, potentially indicating utricle or nerve damage.
• The established bucket method involves aligning a line to vertical in a randomly rotated bucket.

Purpose of the Study:

• To evaluate the efficacy and accessibility of a Visual Vertical iOS app as a tool for measuring SVV.
• To compare the performance of the iOS app against the validated bedside bucket method.

Main Methods:

• SVV measurements were conducted on 22 healthy participants (16 female, 6 male).
• Each participant completed 10 trials using the bucket test and 10 trials using the iOS app.
• Reliability and validity of the iOS app were analyzed using SPSS21.

Main Results:

• The iOS app demonstrated high internal consistency, with Cronbach's α of 0.978 (plumb line method: 0.976).
• Statistical analysis (Mann Whitney U test) revealed no significant difference in SVV distribution between the iOS app and the bucket method.
• High reliability indicates the app consistently measures SVV.

Conclusions:

• The Visual Vertical iOS app serves as an effective and accessible substitute for the plumb line in the validated bucket test.
• This digital tool provides a modern, reliable method for assessing the subjective visual vertical.
• The app facilitates accurate measurement of vestibular function in a clinical or research setting.