title: A comparison of the accuracy of ultrasound and computed tomography in common diagnoses causing acute abdominal pain.
abstract: OBJECTIVE
  Head-to-head comparison of ultrasound and CT accuracy in common diagnoses causing acute abdominal pain.
  
  
  METHODS
  Consecutive patients with abdominal pain for >2 h and <5 days referred for imaging underwent both US and CT by different radiologists/radiological residents. An expert panel assigned a final diagnosis. Ultrasound and CT sensitivity and predictive values were calculated for frequent final diagnoses. Effect of patient characteristics and observer experience on ultrasound sensitivity was studied.
  
  
  RESULTS
  Frequent final diagnoses in the 1,021 patients (mean age 47; 55% female) were appendicitis (284; 28%), diverticulitis (118; 12%) and cholecystitis (52; 5%). The sensitivity of CT in detecting appendicitis and diverticulitis was significantly higher than that of ultrasound: 94% versus 76% (p < 0.01) and 81% versus 61% (p = 0.048), respectively. For cholecystitis, the sensitivity of both was 73% (p = 1.00). Positive predictive values did not differ significantly between ultrasound and CT for these conditions. Ultrasound sensitivity in detecting appendicitis and diverticulitis was not significantly negatively affected by patient characteristics or reader experience.
  
  
  CONCLUSIONS
  CT misses fewer cases than ultrasound, but both ultrasound and CT can reliably detect common diagnoses causing acute abdominal pain. Ultrasound sensitivity was largely not influenced by patient characteristics and reader experience.
authors.affiliation: Department of Radiology (Suite G1-227), Academic Medical Centre, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. a.vanranden@amc.uva.nl
authors.forename: Adrienne
authors.initials: A
authors.lastname: van Randen
authors.forename: Wytze
authors.initials: W
authors.lastname: Laméris
authors.forename: H Wouter
authors.initials: HW
authors.lastname: van Es
authors.forename: Hans P M
authors.initials: HP
authors.lastname: van Heesewijk
authors.forename: Bert
authors.initials: B
authors.lastname: van Ramshorst
authors.forename: Wim
authors.initials: W
authors.lastname: Ten Hove
authors.forename: Willem H
authors.initials: WH
authors.lastname: Bouma
authors.forename: Maarten S
authors.initials: MS
authors.lastname: van Leeuwen
authors.forename: Esteban M
authors.initials: EM
authors.lastname: van Keulen
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Bossuyt
authors.forename: Jaap
authors.initials: J
authors.lastname: Stoker
authors.forename: Marja A
authors.initials: MA
authors.lastname: Boermeester
mesh_terms: D000006:Abdomen, Acute / Q000000981:diagnostic imaging* / Q000209:etiology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001064:Appendicitis / Q000150:complications / Q000000981:diagnostic imaging; D002764:Cholecystitis / Q000150:complications / Q000000981:diagnostic imaging; D004238:Diverticulitis / Q000150:complications / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014463:Ultrasonography