Today’s pearl is short and sweet. Here’s a breakdown of common radiologic studies performed in the emergency department along with their sensitivities and specificities according to the available literature. You may be surprised by some of the findings and lack of evidence for commonly obtained studies.


Sensitivity/Specificity (%) Plain Film Sensitivity/Specificity (%) CT Sensitivity/Specificity (%) Ultrasound
Small Bowel Obstruction 79-83/67-83 96/100 (fine cuts) 83/100
Nephrolithiasis 63/69 96/100 54/71 (although no difference from CT for clinically relevant stones)
Pneumonia 43.5/93 Reference 94/96
Traumatic Pneumothorax 75.5/100 Reference 98.1/99.2
Cholelithiasis 15-20 (no specificity found) 79.1/100 98/98
Retropharyngeal Abscess in Children 80/100 (small study) 64-100/45-82 (varies by study) Seems high, although large studies have yet to be done.


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May 2024