Do published guidelines predict pneumonia in children presenting to an urban ED?

Objectives: In 1997, a Canadian task force published evidence-based guidelines for diagnosing pediatric pneumonia, concluding that the absence of each of four signs (ie, respiratory distress, tachypnea, crackles, and decreased breath sounds) accurately excludes pneumonia. The study was performed to evaluate the accuracy of these guidelines in predicting pneumonia in young children. Methods: This was an observational study conducted over a 4-month period at an urban emergency department with 80,000 annual visits, approximately 20% of which were children ≤5 years old. Consecutive children ≤5 years old who underwent chest radiography were enrolled. Prior to ordering radiographs, treating physicians were required to enter specific patient signs and symptoms into a computerized database. World Health Organization criteria were used to define tachypnea. Sensitivity, specificity, and predictive values of the task force guidelines in predicting pneumonia were calculated. Results: Three hundred twenty-nine children, including 67 (20%) with pneumonia, were enrolled. Guidelines were 45% sensitive (95% confidence interval (CI) = 33-58) and 66% specific (95% CI = 60-72) for diagnosing pneumonia. Positive and negative predictive values were 25% (95% CI = 18-34) and 82% (95% CI = 77-87), respectively. Conclusion: Previously published evidence-based guidelines for excluding pediatric pneumonia were found unreliable in this study.