title: Inter-reader Variability in the Use of BI-RADS Descriptors for Suspicious Findings on Diagnostic Mammography: A Multi-institution Study of 10 Academic Radiologists.
abstract: The study aimed to determine the inter-observer agreement among academic breast radiologists when using the Breast Imaging Reporting and Data System (BI-RADS) lesion descriptors for suspicious findings on diagnostic mammography.
  
  
  
  Ten experienced academic breast radiologists across five medical centers independently reviewed 250 de-identified diagnostic mammographic cases that were previously assessed as BI-RADS 4 or 5 with subsequent pathologic diagnosis by percutaneous or surgical biopsy. Each radiologist assessed the presence of the following suspicious mammographic findings: mass, asymmetry (one view), focal asymmetry (two views), architectural distortion, and calcifications. For any identified calcifications, the radiologist also described the morphology and distribution. Inter-observer agreement was determined with Fleiss kappa statistic. Agreement was also calculated by years of experience.
  
  
  
  Of the 250 lesions, 156 (62%) were benign and 94 (38%) were malignant. Agreement among the 10 readers was strongest for recognizing the presence of calcifications (k = 0.82). There was substantial agreement among the readers for the identification of a mass (k = 0.67), whereas agreement was fair for the presence of a focal asymmetry (k = 0.21) or architectural distortion (k = 0.28). Agreement for asymmetries (one view) was slight (k = 0.09). Among the categories of calcification morphology and distribution, reader agreement was moderate (k = 0.51 and k = 0.60, respectively). Readers with more experience (10 or more years in clinical practice) did not demonstrate higher levels of agreement compared to those with less experience.
  
  
  
  Strength of agreement varies widely for different types of mammographic findings, even among dedicated academic breast radiologists. More subtle findings such as asymmetries and architectural distortion demonstrated the weakest agreement. Studies that seek to evaluate the predictive value of certain mammographic features for malignancy should take into consideration the inherent interpretive variability for these findings.
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115. Electronic address: amie.lee2@ucsf.edu.
authors: Amie Y
authors: AY
authors: Lee
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115.
authors: Dorota J
authors: DJ
authors: Wisner
authors: Department of Radiology, University of California, Davis, California.
authors: Shadi
authors: S
authors: Aminololama-Shakeri
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115.
authors: Vignesh A
authors: VA
authors: Arasu
authors: Department of Radiological Sciences, University of California, Irvine, California.
authors: Stephen A
authors: SA
authors: Feig
authors: Department of Radiology, University of California, Davis, California.
authors: Jonathan
authors: J
authors: Hargreaves
authors: Department of Radiology, University of California, San Diego, California.
authors: Haydee
authors: H
authors: Ojeda-Fournier
authors: Breast Imaging Section, Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California.
authors: Lawrence W
authors: LW
authors: Bassett
authors: Breast Imaging Section, Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, California.
authors: Colin J
authors: CJ
authors: Wells
authors: Department of Radiology, University of California, San Diego, California.
authors: Jade
authors: J
authors: De Guzman
authors: Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California.
authors: Chris I
authors: CI
authors: Flowers
authors: Department of Radiological Sciences, University of California, Irvine, California.
authors: Joan E
authors: JE
authors: Campbell
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115.
authors: Sarah L
authors: SL
authors: Elson
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115.
authors: Hanna
authors: H
authors: Retallack
authors: Department of Radiology and Biomedical Imaging, University of California, 1600 Divisadero Street, Room C250, Box 1667, San Francisco, CA 94115.
authors: Bonnie N
authors: BN
authors: Joe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000473:pathology*; D002983:Clinical Competence / Q000592:standards; D005260:Female; D006268:Health Facilities; D006801:Humans; D008327:Mammography / Q000592:standards*; D008875:Middle Aged; D015588:Observer Variation; D000072177:Radiologists / Q000592:standards*; D012189:Retrospective Studies
keywords: BI-RADS; Breast Imaging; Mammography