Radiology residents' on-call interpretation of chest radiographs for pneumonia.

RATIONALE AND OBJECTIVES: This study is designed to assess the performance of radiology residents in interpreting emergency department chest radiographs for pneumonia and to characterize chest radiographic findings in patients for which interpretation was amended by an attending radiologist.

MATERIALS AND METHODS: We retrospectively reviewed all amended reports for chest radiographs performed on emergency department patients July 2002-June 2003. Reports preliminarily interpreted by residents and amended by a board-certified staff radiologist for the presence or absence of pneumonia were identified. A panel of three experienced radiologists, blinded to reports, jointly reviewed each chest radiograph. If the panel diagnosed pneumonia, the chest radiograph was evaluated for the projection that best showed the pneumonia, its size and location, and the presence or absence of the following features: increased opacity, air bronchograms, loss of vascular markings, silhouette sign, and linear opacities. The resident's post-graduate year (PGY) training level was noted.

RESULTS: One percent (134/12,600 reports) of chest radiographic reports were amended for the presence or absence of pneumonia. One hundred chest radiographs were available and comprised the series. There were 56 females and 44 males with a mean age of 45 years (range, 1-99 years). The staff radiologist diagnosed pneumonia in 79% (79/100 radiographs). The panel agreed with the staff in 77% (kappa = 0.76) and the resident in 23% (kappa = 0.43). The panel diagnosed pneumonia in 60% (60/100 radiographs) with the following chest radiographic findings: 100% (60/60), increased opacity; 37% (22/60), air bronchograms; 72% (43/60), loss of vascular markings; 40% (24/60), silhouette sign; and 20% (12/60), linear opacities. The pneumonia was right sided in 52% (31/60), left sided in 37% (22/60), and bilateral in 11% (7/60). Right-sided pneumonias were equally distributed among the three lobes, and left-sided pneumonias had a lower-lobe predominance of 77% (17/22). Seventy-five percent (45/60) of pneumonias were segmental or smaller, and 82% (49/60) of chest radiographs showing pneumonia had both posteroanterior and lateral projections. The pneumonia was conspicuous on only one projection in 43% (21/49); the posteroanterior view in 22% (11/49), and the lateral view in 20% (10/49). Eighty-one percent (81/100) of interpreting residents were PGY-3.

CONCLUSION: Interpretation of chest radiographs for pneumonia by PGY-3 residents has a low error rate. Missed pneumonias often were segmental or smaller and conspicuous on only one projection.