Impact of clinical history on chest radiograph interpretation.

BACKGROUND: The inclusion of clinical information may have unrecognized influence in the interpretation of diagnostic testing.
OBJECTIVE: The objective of the study was to determine the impact of clinical history on chest radiograph interpretation in the diagnosis of pneumonia.
DESIGN: Prospective case-based study.
METHODS: Radiologists interpreted 110 radiographs of children evaluated for suspicion of pneumonia. Clinical information was withheld during the first interpretation. After 6 months the radiographs were reviewed with clinical information. Radiologists reported on pneumonia indicators described by the World Health Organization (ie, any infiltrate, alveolar infiltrate, interstitial infiltrate, air bronchograms, hilar adenopathy, pleural effusion).
SETTING: Children's Hospital of Philadelphia and Boston Children's Hospital. PARTICIPANTS: Six board-certified radiologists. OUTCOME MEASURES: Inter- and inter-rater reliability were assessed using the kappa statistic.
RESULTS: The addition of clinical history did not have a substantial impact on the inter-rater reliability in the identification of any infiltrate, alveolar infiltrate, interstitial infiltrate, pleural effusion, or hilar adenopathy. Inter-rater reliability in the identification of air bronchograms improved from fair (k = 0.32) to moderate (k = 0.53). Intra-rater reliability for the identification of alveolar infiltrate remained substantial to almost perfect for all 6 raters with and without clinical information. One rater had a decrease in inter-rater reliability from almost perfect (k = 1.0) to fair (k = 0.21) in the identification of interstitial infiltrate with the addition of clinical history.
CONCLUSIONS: Alveolar infiltrate and pleural effusion are findings with high intra- and inter-rater reliability in the diagnosis of bacterial pneumonia. The addition of clinical information did not have a substantial impact on the reliability of these findings.