title: Markers of good performance in mammography depend on number of annual readings.
abstract: OBJECTIVE
  To explore relationships between reader performance and reader characteristics in mammography for specific radiologist groupings on the basis of annual number of readings.
  
  
  METHODS
  The institutional review board approved the study and waived the need for patient consent to use all images. Readers gave informed consent. One hundred sixteen radiologists independently reviewed 60 mammographic cases: 20 cases with cancer and 40 cases with normal findings. Readers located any visualized cancer, and levels of confidence were scored from 1 to 5. A jackknifing free response operating characteristic (JAFROC) method was used, and figures of merit along with sensitivity and specificity were correlated with reader characteristics by using Spearman techniques and standard multiple regressions.
  
  
  RESULTS
  Reader performance was positively correlated with number of years since qualification as a radiologist (P ≤ .01), number of years reading mammograms (P ≤ .03), and number of readings per year (P ≤ .0001). The number of years since qualification as a radiologist (P ≤ .004) and number of years of reading mammograms (P ≤ .002) were negatively related to JAFROC values for radiologists with annual volumes of less than 1000 mammographic readings. For individuals with more than 5000 mammographic readings per year, JAFROC values were positively related to the number of years that the reader was qualified as a radiologist (P ≤ .01), number of years of reading mammograms (P ≤ .002), and number of hours per week of reading mammograms (P ≤ .003). Number of mammographic readings per year was positively related with JAFROC scores for readers with an annual volume between 1000 and 5000 readings (P ≤ .03). Differences in JAFROC scores appear to be more related to specificity than location sensitivity, with the former demonstrating significant relationships with four of the five characteristics analyzed, whereas no relationships were shown for the latter.
  
  
  CONCLUSIONS
  Radiologists' determinants of performance are associated with annual reading volumes. Ability to recognize normal images is a discriminating factor in individuals with a high volume of mammographic readings.
authors.affiliation: Medical Image Optimisation and Perception Group, Medical Imaging and Radiation Sciences, Faculty Research Group, Faculty of Health Sciences, the University of Sydney, Cumberland Campus, 75 East St, Lidcombe, NSW 2141, Australia.
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Rawashdeh
authors.forename: Warwick B
authors.initials: WB
authors.lastname: Lee
authors.forename: Roger M
authors.initials: RM
authors.lastname: Bourne
authors.forename: Elaine A
authors.initials: EA
authors.lastname: Ryan
authors.forename: Mariusz W
authors.initials: MW
authors.lastname: Pietrzyk
authors.forename: Warren M
authors.initials: WM
authors.lastname: Reed
authors.forename: Robert C
authors.initials: RC
authors.lastname: Heard
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Black
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Brennan
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008327:Mammography / Q000706:statistics & numerical data*; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D015588:Observer Variation; D015995:Prevalence; D011361:Professional Competence / Q000706:statistics & numerical data*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014463:Ultrasonography