Prevalence of abnormal chest X-rays in study population: 19%
Criteria for pulmonary findings - one or more of the following:
(1) respiratory distress (nasal flaring, grunting and/or intercostal retractions)
(2) tachypnea
(3) rales
(4) decreased breath sounds
Tachypnea is the best single predictor of an abnormal chest X-ray.
Limiting chest X-rays to children with one or more pulmonary findings would have reduced the number of chest X-rays by 30% without missing a case with an abnormal X-ray (100% sensitive but nonspecific).
(1) For children < 2 years of age, positive X-rays were present in 21% when pulmonary findings were present.
(2) For children >= 2 years of age, positive X-rays were present in 37% when pulmonary findings were present.
Limitations of study:
• Since the study was done on patients at an emergency department, the children may have been sicker and/or had a higher rate of pneumonia compared to that seen in other settings. This would affect the performance characteristics for the ordering criteria.
