Breathlessness is an important symptom of respiratory disease and its quant
ification is useful, especially during exercise testing. However, measures
of perceived breathlessness are not readily understood by children and are
somewhat subjective. We studied an objective score: the 15-count breathless
ness score, in which subjects take a deep breath and then count out loud to
15; the number of breaths taken to complete the count is the score. Fifty-
four children with cystic fibrosis (GF) performed a standard B-min walk and
3-min step test (30 steps/min for 3 min). The 15-count score was compared
with the modified Borg scale after exercise. A further 45 children with CF
and 33 healthy schoolchildren underwent an incremental step test (20, 30, a
nd then 40 steps/min for 2 min each), using the 15-count score, then the Bo
rg scale, and then a standard visual analogue score between increments.
The 15-count score was significantly increased after both the walk and the
step test (P < 0.0001), although the step test made children significantly
more breathless than the walk test (P < 0.0001). At baseline, there were no
differences in any of the breathlessness scores between the CF and normal
children. After the full 6 min of the incremental step test, CF children we
re significantly more breathless than the normal children, as measured by 1
5-count (P < 0.0001), Borg (P < 0.0005), and visual analogue scores (P < 0.
0005), All scores increased significantly as exercise intensity increased o
ver time, but the slope estimates were significantly greater for CF patient
s than for normal children (P < 0.0005).
The 15-count score has been evaluated as an objective measure of breathless
ness. It is easy to explain and perform, and can be used by any child capab
le of counting fluently to 15 in any language. It is best used in conjuncti
on with a subjective score, and either the Borg scale or a visual analogue
score is appropriate. (C) 2000 Wiley-Liss. Inc.