Tachypnea seems to be the most significant
clinical sign. To be measured accurately, the
respiratory rate must be counted over a full
minute when the child is quiet.15 In febrile
children, the absence of tachypnea has a high
negative predictive value (97.4 percent) for
pneumonia.1,15,16 Conversely, the presence of
tachypnea in febrile children has a low positive
predictive value (20.1 percent).15 Fever
alone can increase the respiratory rate by