Information Technology Reference
In-Depth Information
Fuzzy Numerical Rating Scale (FNRS)
The fuzzy numerical rating scale consists of a graded line scale identified by eleven
numbers from 0 to 10 (Fig. 24.1b). The equivalence to pain intensity is obtained
with
no pain
corresponding to 0 while
maximum pain
is related to 10. The patient
marks this scale,
x
, with the pain intensity that better represents the assumed phys-
ical discomfort. Likewise FVAS, when there is a mark in the line it is related to
the core of a membership function that assumes a full degree,
1. Due to
the subjective, vague representation of pain in the scale and no accuracy in read-
ing the actual value, then the uncertainty and imprecision of marked value is best
represented by a fuzzy set Fig. 24.1c. Similarly, approximately 2, and about 5 are,
respectively, described by Gaussian and triangular fuzzy sets.
μ
A
(
x
)
=
(a) Visual Analog Scale (VAS)
(b) Numerical Rating Scale (NRS)
(c) Fuzzy NRS (FNRS)
Fig. 24.1
Unidimensional Fuzzy Scales (FVAS) [3]
In a glimpse, observe that the Fuzzy Visual Analog Scale and the Fuzzy Numer-
ical Rating Scale are twosome since VAS also maps the marked value in a numeric
scale with the support of the ruler of computer program.
