Observer variability in screen-film mammography versus full-field digital mammography with soft-copy reading

Abstract

Full-field digital mammography (FFDM) with soft-copy reading is more complex than screen-film mammography (SFM) with hard-copy reading. The aim of this study was to compare inter- and intraobserver variability in SFM versus FFDM of paired mammograms from a breast cancer screening program. Six radiologists interpreted mammograms of 232 cases obtained with both techniques, including 46 cancers, 88 benign lesions, and 98 normals. Image interpretation included BI-RADS categories. A case consisted of standard two-view mammograms of one breast. Images were scored in two sessions separated by 5 weeks. Observer variability was substantial for SFM as well as for FFDM, but overall there was no significant difference between the observer variability at SFM and FFDM. Mean kappa values were lower, indicating less agreement, for microcalcifications compared with masses. The lower observer agreement for microcalcifications, and especially the low intraobserver concordance between the two imaging techniques for three readers, was noticeable. The level of observer agreement might be an indicator of radiologist performance and could confound studies designed to separate diagnostic differences between the two imaging techniques. The results of our study confirm the need for proper training for radiologists starting FFDM with soft-copy reading in breast cancer screening.

Prospective trial comparing full-field digital mammography (FFDM) versus combined FFDM and tomosynthesis in a population-based screening programme using independent double reading with arbitration

“…The success of screening mammography depends on the detection of small, subtle non-palpable cancers which may be a very difficult task. Consequently, inter-observer and intra-observer variability that may be affected by many factors such as case difficulty, radiologist’s experience, varying practices and others, is a great challenge in mammographic screening and has been shown to be a great problem for SFM as well as FFDM [4, 5]. In a nationwide mammography screening programme using independent double reading, a total of 23 % of the screening-detected cancers had a discordant interpretation, i.e.…”

Predictors of interobserver agreement in breast imaging using the Breast Imaging Reporting and Data System

“…Two studies were written in German with no English translation [24, 25] and thus excluded as well. Two studies evaluated only intraobserver agreement [26, 27], one study compared observer responses to a study-defined gold standard [18], one reported only mean kappas [30], one measured agreement between crainocaudal and mediolateral oblique view ratings [22] and three measured agreement between film screen and digital mammogram ratings [17, 28,29]. Lastly, we excluded two additional studies because agreement was not measured on BI-RADS terminology and/or final assessment categories.…”

The effect of digitising film prior mammograms on radiologists' performance in breast screening: a JAFROC study

“…It is not clear whether this affected their performance. Per Skaane et al 16 found considerable intra and inter observer variation in their examination of screen film reporting and full field digital mammography. They interpret their findings as indicating the need for proper training for soft copy reading.…”