Pain assessment is the key to the effective treatment of both acute and chronic pain. Pain is a multifaceted phenomenon; a mixture of sensory, emotional and cultural experiences. As pain is a complex internal event, self-reports are becoming valuable tools in research and practice. The visual analog scale (VAS), in particular, is one of the most popular subjective measurements used in the effective assessment and treatment of pain intensity.
The visual analog scale, also known as the graphic rating scale is a simple, valid and reliable subjective measure. Interestingly, the scale was used for the first time in 1921, by Hayes and Patterson. The visual analog scale allows patients to assess their pain experiences with high precision. Scores are ranked on a 10-cm line that stretches between two extremes – “no pain” and “worst pain” (Delgado et al., 2018). Note that this scale can be represented as a horizontal or a vertical line. Moreover, the visual analog scale is a versatile continuous scale which can be applied to a wide range of clinical settings, such as labor pain, neuropathic pain, fatigue in chronic pain, and patients’ quality of life.