Does the strength of the gist signal predict the difficulty of breast cancer detection in usual presentation and reporting mechanisms?

摘要

This study measured the correlation between the magnitude of the presence of theabnormality gist and case difficulty based on standard presentation and reporting mechanisms for80 cases. Half of the cases contained biopsy-proven cancer while the remainder were normal andconfirmed to be cancer-free for at least two years of follow-up. In the gist experiment, seventeenbreast radiologists and physicians gave an abnormality score on a scale from 0 (confident normal)to 100 (confident abnormal) to unilateral CC mammograms following a very brief, 500 millisecondpresentation of the image. Independently, each mammogram was assessed by a separate sampleof at least 40 radiologists using standard presentation and reporting mechanisms, with thesereaders asked to locate any cancers present. All readers reported at least 1000 cases annually. Foreach case and each category, the percentage of correct reports served as an objective measure ofcase difficulty (lower rate of correct report shows a more difficult case). For each of the 17 readers,the association between the abnormality scores from the gist study and detection rates from theearlier reports was examined using Spearman correlation. None of the coefficients weresignificantly different from zero (p>0.05). For the normal cases, the correlation coefficient betweenabnormality scores and detection rates for the 17 readers ranged from -0.262 to 0.258, and forcancer -0.180 to 0.309. The results suggest that the gist signal may indicate the presence ofcancer, using mechanisms other than those employed in usual reporting, and might be exploited toimprove breast cancer detection.