Civil Engineering Reference
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TABLE 37.3 Fleishman Index of
Perceived Physical Effort
1
Very, very light
2
3
4
Somewhat hard
5
6
7
Very, very hard
seven-point category scale with values from 1 to 7, each number anchored with verbal descriptions from
1
somewhat hard. In the first study (Hogan and
Fleishman, 1979) the proposed index was applied to assessment of 37 occupational and 62 recreational
tasks whose metabolic costs had been previously determined. In the second study (Hogan et al., 1980)
energy expenditure for 24 manual handling tasks were measured and perceived effort were assessed.
Both studies supported validity and reliability of the physical effort scale. The results showed high
interrater agreement (0.83) among subjects concerning the perceived effort needed to perform the
assessed tasks. The ratings of perceived effort were highly related (0.83-0.88) to estimated metabolic
costs. Subjects were also able to make distinction between tasks at all ranges of physical effort. Similarities
in ratings of perceived exertion suggest that group ratings of perceived effort can be used to accurately
reflect metabolic costs of task performance (Fleishman et al., 1984), as opposed to individual ratings that
only represent the effort perceived by one person and do not always accurately represent perception of
population.
very, very light, to 7
very, very hard, and 4
¼
¼
¼
37.3.2.2 Pittsburgh Perceived Exertion Scale
The Pittsburgh perceived exertion scale (Table 37.4) is a nine-point category scale with terminal
expressions of 2 and 8 on the scale (Noble and Robertson, 1996). These numbers were used intentionally
in order to avoid the “end effect” of category scales, when subjects tend to use the middle of the scale.
When the absolute ends of the scale are not verbally anchored, the use of the terminal expressions
increases. Ratings on this scale have been shown to correlate well with the heart rate and power
output (Noble and Robertson, 1996).
37.3.3 Subjective Scales for Postural Assessment
37.3.3.1 Body Part Discomfort Scale
The Body Part Discomfort (BPD) Scale (Corlett and Bishop, 1976) has been adopted technique for
assessment of postural discomfort. Corlett and Bishop (1976) analyzed the relationship between the per-
ceived discomfort level and holding time, that is, the amount of time a subject could hold different pos-
tures before voluntary termination of the posture. This research demonstrated that if a force was exerted
TABLE 37.4 Pittsburgh Perceived Exertion Scale
1
2
Not at all stressful
3
4
5
6
7
8
Very, very stressful
9
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