Chapter 5 Pain Assessment Flashcards
KEY POINTS 1. Pain is a subjective, private, internal experience 2. While there is currently no “objective” measure of pain, a number of self-report pain assessment tools have proven to be valid and reliable 3. Specialized pain assessment scales are available for special populations (e.g., children) 4. Psychophysiologic, behavioral, and functional neuroimaging-based assessment methods cannot substitute for an individual’s self-reported pain experience 5. Biases in estimating another person’
Three most commonly used methods to quantify the pain experience
verbal rating scales, numerical rating scales, and visual analog scales
VERBAL RATING SCALES (VRS)
A VRS generally consists of a series of adjectives (or phrases), ordered from least intense (or unpleasant) to most intense (or unpleasant). An adequate VRS should span a maximum possible range of the pain experience (e.g., from “no pain” to “extremely intense pain”)
Verbal Rating Scale (VRS) for Pain Intensity
None 0
Mild 1
Moderate 2
Severe 3
Very Severe 4
VRS weaknesses
First, the scoring method for VRS assumes equal intervals
between adjectives. That is, the change in pain from
“none” to “mild” is quantified identically with the change
in pain from “moderate” to “severe.
Second, in order to
properly use a VRS, a patient must both be familiar with
all of the words used on the scale, and must be able
to find one that accurately describes his or her pain.
NUMERICAL RATING SCALES (NRS)
An NRS typically consists of a series of numbers with verbal
anchors representing the entire possible range of pain intensity. Generally, patients rate their pain from 0 to 10, from 0 to 20, or from 0 to 100. Zero represents “no pain” whereas the 10, 20, or 100 represents the opposite end of the pain continuum (e.g., “the most intense pain imaginable,,”
“pain as intense as it could be,,” “maximum pain”)
Weakness of the NRS
The principal weakness of the NRS is that, statistically, it does not have ratio qualities. That is, numerically equal intervals on the scale (e.g., the difference between 1 and 3 and the difference between 7 and 9) may not represent equivalent intervals in terms of scaling the
intensity of pain. One other limitation of most NRS measures of pain is that individuals’ ratings of a given pain experience can be altered in idiosyncratic ways by the
choice of anchors on the upper end of the scale
VISUAL ANALOG SCALES (VAS)
A VAS consists of a line, often 10 cm long, with verbal anchors at either end, similar to an NRS (e.g., “no pain” on the far left and “the most intense pain imaginable” on the far right). The patient places a mark at a point on the line corresponding to the patient’s rating of pain intensity
VAS limitations
- It can be difficult to administer to patients with perceptual motor problems
- VAS is generally scored using a ruler (the score is the number of centimeters or millimeters from the end of the line), making
scoring more time consuming and adding additional possible sources of bias or error. - relative to other rating scales, use of a VAS produces higher non-completion rates among certain populations, primarily among those with cognitive limitations and among elderly samples
MCGILL PAIN QUESTIONNAIRE (MPQ)
three dimensions of the experience of pain:
sensory-discriminative, affectivemotivational,
and cognitive-evaluative. The MPQ was created to assess these multiple aspects of pain
MCGILL PAIN QUESTIONNAIRE (MPQ)
It consists of 20 sets of verbal descriptors, ordered in intensity
from lowest to highest. These sets of descriptors are divided
into those assessing the sensory (10 sets), affective (5 sets), evaluative (1 set), and miscellaneous (4 sets) dimensions of pain.
How is the MPQ performed?
Patients select the words that describe their pain, and their word selections are converted into a pain rating index, based on the sum of all of the words
after they are assigned a rank value, as well as the total
number of words chosen. In addition, the MPQ contains
a present pain intensity VRS (i.e., the PPI), ordered from “mild” to “excruciatinG
How is Pain relief measured?
using a VAS, a VRS with gradations of relief (e.g., “none,” “slight,”“moderate,” “complete”), or an NRS assessing the percentage of relief
How is Pain relief measured?
using a VAS, a VRS with gradations of relief (e.g., “none,” “slight,”“moderate,” “complete”), or an NRS assessing the percentage of relief
How is Pain relief measured?
using a VAS, a VRS with gradations of relief (e.g., “none,” “slight,”“moderate,” “complete”), or an NRS assessing the percentage of relief
How is Pain relief measured?
using a VAS, a VRS with gradations of relief (e.g., “none,” “slight,”“moderate,” “complete”), or an NRS assessing the percentage of relief