From the Guidelines
The most evidenced visual analog scale (VAS) pain score to use in a clinical setting is the 0-10 Numeric Rating Scale (NRS), as it has been shown to be a valid and feasible pain scale for critically ill adults and is preferred by patients 1.
Key Points
- The 0-10 NRS has been found to have the highest rate of success and is most highly favored by ICU patients 1.
- The VAS has been found to be difficult for many patients to understand and use, with a lower success rate compared to the NRS 1.
- Other pain scales, such as the Verbal Descriptor Scale (VDS) and the Faces Pain Thermometer (FPT), may also be useful in certain situations, but the 0-10 NRS is generally recommended 1.
- The use of a simple numeric rating scale, such as the 0-10 NRS, is recommended for assessing pain intensity in patients with painful diabetic peripheral neuropathy 1.
- The 0-10 NRS is also recommended for use in patients living with HIV, as part of a comprehensive pain assessment 1.
Important Considerations
- Pain is a subjective experience and should be assessed using a patient-reported outcome measure, such as the 0-10 NRS 1.
- The 0-10 NRS is a widely used and validated measure of pain intensity, and is suitable for use in a variety of clinical settings 1.
From the Research
Visual Analog Scale (VAS) Pain Score
The most evidenced VAS pain score to use in a clinical setting is a topic of ongoing research.
- A study published in 2003 2 suggested that 100-mm VAS ratings can be interpreted as follows:
- 0 to 4 mm: no pain
- 5 to 44 mm: mild pain
- 45 to 74 mm: moderate pain
- 75 to 100 mm: severe pain
- Another study published in 2011 3 compared the validity of VAS with other pain intensity rating scales and found that VAS is a valid measure of pain intensity, although it may not be the most responsive scale.
- The linearity of the VAS has been studied in several papers, including one published in 1999 4 which found that the VAS is linear for mild-to-moderate pain, and another published in 2005 5 which found that the VAS is a linear scale in subjects with severe acute pain.
- A 2014 study 6 introduced the general Labeled Magnitude Scale (gLMS) as a potential alternative to the VAS, which may overcome the limitations of the VAS, particularly the ceiling effect.
Key Findings
- The VAS is a widely used and valid measure of pain intensity 3, 2, 4, 5.
- The VAS has been found to be linear for mild-to-moderate pain 4 and severe acute pain 5.
- A 33% decrease in pain has been suggested as a reasonable standard for determining that a change in pain is meaningful from the patient's perspective 2.