Visual analogue scale

Visual Analogue Scale

The Visual Analogue Scale (VAS) is a psychometric response scale which can be used in questionnaires. It is a measurement instrument for subjective characteristics or attitudes that cannot be directly measured. When responding to a VAS item, respondents specify their level of agreement to a statement by indicating a position along a continuous line between two end-points.

History[edit | edit source]

The Visual Analogue Scale was first described in the early 20th century for the measurement of subjective phenomena. It has been widely used in different fields such as psychology, medicine, and social sciences.

Structure and Use[edit | edit source]

A typical VAS is a horizontal line, 100 mm in length, anchored by word descriptors at each end. The respondent marks on the line the point that they feel represents their perception of their current state. The VAS score is determined by measuring in millimeters from the left hand end of the line to the point that the patient marks.

VAS is used to measure intensity or frequency of various symptoms such as pain, nausea, fatigue, and anxiety. It is also used in social sciences to measure attitudes.

Advantages and Disadvantages[edit | edit source]

The main advantage of the VAS is its simplicity. It is easy to understand and can be used with a wide range of populations. It also allows for a high degree of sensitivity in capturing changes over time.

However, the VAS has been criticized for its lack of objectivity. The interpretation of the scale can vary greatly among different individuals. Furthermore, it requires a certain level of cognitive and motor skills, which may limit its use with certain populations.