What Is a Visual Analogue Scale?

A visual analogue scale, often featuring a numerical rating, generally relates to human psychology and the measurement of characteristics like skill, confidence, or satisfaction. It can also be used to gauge one’s knowledge, personality, or attitude with the use of questionnaires and tests. Pain is another trait that a visual analogue scale is often used for; both patients and health care workers can rate pain level using a numerical, color-based scale.

Some scales consist of only a blank line, with two alternative characteristics on either end. A respondent typically has the choice of marking some point in between; the Likert scale, for example, usually includes a set of word choices measuring happiness. There are typically from four to seven options that help to determine one’s satisfaction with something. A visual analogue scale, however, typically combines numbers and colors to determine the level of feeling someone has.

The numeric pain rating scale is typically one with different colors that can help a person select an accurate level of the discomfort felt. Usually about 4 inches (about 10 centimeters) long, it also uses the distance between markings to analyze pain variables. The pain someone is in when first reached by a paramedic, and at the time of hospital admission are often analyzed. By calculating the difference between the two, physicians can gauge the effects of pain relief in a medical setting.

Various medical studies have used a visual analogue scale as well. Researchers can accurately gauge the pain level of patients and coordinate the data based on markings on each scale. The tool has been modified over time by assessing its use relative to how many levels were included. One scale had over 100 levels to indicate pain, but many people found it difficult to mentally process so many choices. A scale of 10 is often effective, while some include three or four categories.

Pain can also be tracked based not only by intensity, but over time. Intensity can be tracked while one performs a certain activity; it is possible to mark a pain level at the start of the activity as well as at the end. Some versions of the visual analogue scale allow a person to write down what it is he or she is doing that causes the discomfort. The date and duration time can be included as well. By using this method, sometimes the cause of a problem can be determined, while a pain management strategy that can also help an injury heal, for example, may be assessed.