Reliability of the Visual Analog Scale

The visual analog scale (VAS) is a type of assessment tool that measures subjective complaints of pain. It consists of a vertical (or horizontal) line, 10 centimeters (cm) in length, representing pain complaints on a scale of 0 (no pain at all) to 10 (worst pain you have ever felt).

Uses

• The VAS can be used to compare the level of pain an individual is experiencing at a certain point in time with their pain level at a later point in time. For example, it is helpful for comparing pre-operative pain with post-operative pain. It can also be used to assess how much a person's pain has decreased after using pain medication.

Reliability

• For an assessment to be considered reliable, it must produce consistent and compatible results each time it is used. Scientific research has proven the VAS to be a reliable assessment tool for pain.