title: Development and implementation of an appropriateness guideline for use of CT in cases of suspected intraabdominal abscess.
abstract: OBJECTIVE
  The purpose of this study was to develop an evidence-based guideline for use of computed tomography (CT) in the evaluation of suspected abdominal abscess. The goal of the guidelines was to decrease the absolute number of CT examinations performed for suspected abdominal abscess and to increase the rate of positive CT examinations while not missing clinically relevant abscesses.
  
  
  METHODS
  A multidisciplinary team developed an evidence-based guideline regarding use of CT to evaluate for suspected abscess. A control group consisted of patients scanned for suspected abscess during a 6-month period. The intervention group consisted of patients scanned in the 6 months after guideline implementation. Focal fluid collections depicted on CT scans were reviewed for both patient groups to determine if these collections were abscesses. The number and proportion of abscesses in each group were then compared.
  
  
  RESULTS
  During the control period, 263 CT examinations for suspected abscess were performed, 75 of which (28.5%; 90% confidence interval [CI], 24%, 33%) depicted focal fluid and 25 of which (9.5%; 90% CI, 7%, 12%) depicted abscess. During the intervention period, 238 CT examinations were performed, 54 of which (22.7%; 90% CI, 18%, 27%) depicted fluid and 41 of which (17.2%; 90% CI, 13%, 21%) depicted abscess.
  
  
  CONCLUSIONS
  A guideline was successful at decreasing the number of CT examinations and increasing the proportion of positive CT results for abdominal abscess. As with other inpatient utilization interventions, each practice must assess the cost-benefit trade-off of guideline implementation in complex clinical situations.
authors.affiliation: Department of Radiology, University of Michigan Medical Center, Ann Arbor 48109-0326, USA.
authors.forename: N R
authors.initials: NR
authors.lastname: Lal
authors.forename: E A
authors.initials: EA
authors.lastname: Kazerooni
authors.forename: R L
authors.initials: RL
authors.lastname: Bree
mesh_terms: D018784:Abdominal Abscess / Q000000981:diagnostic imaging*; D003625:Data Collection; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed