title: Accuracy and interpretation time of computer-aided detection among novice and experienced breast MRI readers.
abstract: OBJECTIVE
  The purpose of this study was to compare the diagnostic accuracy and interpretation times of breast MRI with and without use of a computer-aided detection (CAD) system by novice and experienced readers.
  
  
  METHODS
  A reader study was undertaken with 20 radiologists, nine experienced and 11 novice. Each radiologist participated in two reading sessions spaced 6 months apart that consisted of 70 cases (27 benign, 43 malignant), read with and without CAD assistance. Sensitivity, specificity, negative predictive value, positive predictive value, and overall accuracy as measured by the area under the receiver operating characteristic curve (AUC) were reported for each radiologist. Accuracy comparisons across use of CAD and experience level were examined. Time to interpret and report on each case was recorded.
  
  
  RESULTS
  CAD improved sensitivity for both experienced (AUC, 0.91 vs 0.84; 95% CI on the difference, 0.04, 0.11) and novice readers (AUC, 0.83 vs 0.77; 95% CI on the difference, 0.01, 0.10). The increase in sensitivity was statistically higher for experienced readers (p = 0.01). Diagnostic accuracy, measured by AUC, for novices without CAD was 0.77, for novices with CAD was 0.79, for experienced readers without CAD was 0.80, and for experienced readers with CAD was 0.83. An upward trend was noticed, but the differences were not statistically significant. There were no significant differences in interpretation times.
  
  
  CONCLUSIONS
  MRI sensitivity improved with CAD for both experienced readers and novices with no overall increase in time to evaluate cases. However, overall accuracy was not significantly improved. As the use of breast MRI with CAD increases, more attention to the potential contributions of CAD to the diagnostic accuracy of MRI is needed.
authors.affiliation: Department of Radiology, Section of Breast Imaging, School of Medicine, University of Washington, Seattle, WA, USA. lehman@u.washington.edu
authors.forename: Constance D
authors.initials: CD
authors.lastname: Lehman
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Blume
authors.forename: Wendy B
authors.initials: WB
authors.lastname: DeMartini
authors.forename: Nola M
authors.initials: NM
authors.lastname: Hylton
authors.forename: Benjamin
authors.initials: B
authors.lastname: Herman
authors.forename: Mitchell D
authors.initials: MD
authors.lastname: Schnall
mesh_terms: D000704:Analysis of Variance; D019540:Area Under Curve; D001943:Breast Neoplasms / Q000175:diagnosis*; D002983:Clinical Competence; D003287:Contrast Media; D003936:Diagnosis, Computer-Assisted; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012984:Software
chemical_list: D003287:Contrast Media