Physician Assessment of the Likelihood of Pneumonia in a Pediatric Emergency Department

Background: The value of physical examination findings in the diagnosis of pneumonia in children may be limited, and the accuracy of physicians in predicting pneumonia is not known. Objective: We sought to determine the correlation between physicians' assessment of the likelihood of pneumonia and radiographic presence of pneumonia. Methods: Prospective observational study of children 21 years or younger presenting to a pediatric emergency department, who had a chest radiography performed for suspicion of pneumonia. Physicians recorded clinical findings and likelihood of pneumonia before obtaining the radiograph. Definite and probable pneumonia was defined by a radiologist's interpretation of the radiograph. Results: Of 2071 children, 147 (7%) had definite radiographic pneumonia, whereas 321 (15%) had probable or definite pneumonia. Among patients perceived to be at lowest risk for pneumonia (<5% prediction), 4.3% (95% confidence interval [CI], 2.9%-5.7%) had definite pneumonia, and 10.0% (95% CI, 8.3%-12.5%) had probable or definite pneumonia. Among children perceived to be at highest risk for pneumonia (>75% prediction), 30.6% (95% CI, 15.5%-45.6%) had definite pneumonia, and 52.8% (95% CI, 37.7%-70.3%) had probable or definite pneumonia. Physicians' estimates of the likelihood of pneumonia were positively correlated with the rate of definite (Spearman rho = 0.15, P < 0.001) and probable or definite radiographic pneumonia (Spearman rho = 0.19, P < 0.001). Conclusions: With some overestimation, physicians' assessment of the likelihood of pneumonia correlates well with radiographic diagnosis of pneumonia.