Visual analogue scales (VAS) refer to a measurement tool widely used in research, particularly in the field of psychology and healthcare, for assessing subjective experiences, opinions, and perceptions. VAS is a self-report instrument that allows individuals to rate their experiences or feelings along a continuous line anchored by two opposing endpoints.
These scales typically consist of a horizontal or vertical line, usually around 10 centimeters in length, with or without numbers indicating the intensity or severity of the evaluated variable. The leftmost and rightmost endpoints represent the extremes of the measured construct, such as "not at all" and "extremely," or "low" and "high," allowing participants to depict their perception between the two limits with a mark on the line.
In many cases, verbal descriptors are provided to help individuals interpret the scale and make more accurate judgments. For instance, a VAS measuring pain might have "no pain" on the left end and "worst possible pain" on the right end. Participants place a mark on the line corresponding to the intensity of the pain they are experiencing.
VAS allows researchers or clinicians to obtain quantitative data from subjective experiences, enabling comparison and statistical analysis across individuals or groups. Although mainly used for rating subjective variables, VAS can also be used to evaluate objective responses, including time and distance estimations, levels of mood, perceived exertion, or satisfaction with a particular treatment or intervention.
Overall, visual analogue scales are valuable tools that provide a simple, yet effective, method for quantifying subjective experiences and perceptions.
