Authors’ conclusions: no single finding reliably differentiates pneumonia from other causes of childhood respiratory diseases. Hypoxia and increased respiratory work are more valid signs than tachypnea and auscultatory findings.
Reviewers’ commentary: some clinical signs, separately or together, may be useful in the diagnosis of pneumonia. Tachypnea, a sign classically recommended by the World Health Organization, is less valid than other signs. The auscultatory findings, probably due to their subjectivity, are not valid findings. However, this study does not allow us to assess the performance and safety of a diagnosis of pneumonia exclusively based on clinical findings.