Inter-observer variability in mammography screening and effect of type and number of readers on screening outcome

Abstract

We prospectively determined the variability in radiologists' interpretation of screening mammograms and assessed the influence of type and number of readers on screening outcome. Twenty-one screening mammography radiographers and eight screening radiologists participated. A total of 106 093 screening mammograms were double-read by two radiographers and, in turn, by two radiologists. Initially, radiologists were blinded to the referral opinion of the radiographers. A woman was referred if she was considered positive at radiologist double-reading with consensus interpretation or referred after radiologist review of positive cases at radiographer double-reading. During 2-year follow-up, clinical data, breast imaging reports, biopsy results and breast surgery reports were collected of all women with a positive screening result from any reader. Single radiologist reading (I) resulted in a mean cancer detection rate of 4.64 per 1000 screens (95% confidence intervals (CI) ¼ 4.23 -5.05) with individual variations from 3.44 (95% CI ¼ 2.30 -4.58) to 5.04 (95% CI ¼ 3.81 -6.27), and a sensitivity of 63.9% (95% CI ¼ 60.5 -67.3), ranging from 51.5% (95% CI ¼ 39.6 -63.3) to 75.0% (95% CI ¼ 65.3 -84.7). Sensitivity at non-blinded, radiologist double-reading (II), radiologist double-reading followed by radiologist review of positive cases at radiographer double-reading (III), triple reading by one radiologist and two radiographers with referral of all positive readings (IV) and quadruple reading by two radiologists and two radiographers with referral of all positive readings (V) were as follows: 68.6% (95% CI ¼ 65.3 -71.9) (II); 73.2% (95% CI ¼ 70.1 -76.4) (III); 75.2% (95% CI ¼ 72.1 -78.2) (IV), and 76.9% (95% CI ¼ 73.9 -79.9) (V). We conclude that screener performance significantly varied at singlereading. Double-reading increased sensitivity by a relative 7.3%. When there is a shortage of screening radiologists, triple reading by one radiologist and two radiographers may replace radiologist double-reading.

Breast cancer screening programmes: Challenging the coexistence with opportunistic mammography

“…In France, organized mammography screening is a free service offered biannually to asymptomatic women aged 50-74 years old and consists of a clinical examination and a two-view mammography. By associating clinical breast examinations with the double reading of normal mammograms by a second radiologist, organized mammography screening (OrgMS) programmes ensure a higher rate of cancer detection at an earlier stage [2][3][4][5][6][7]. In many developed countries, OrgMS programmes coexist with opportunistic mammography screening (OppMS).…”

Is Confidence of Mammographic Assessment a Good Predictor of Accuracy?

“…Although screening mammography is currently the best way to detect early breast cancer, there continues to be unexplained variability in radiologists’ interpretive performance [1–3]. To better understand this variability, studies examining radiologist characteristics associated with clinical accuracy have focused on interpretive volume [4–6], years of experience [5, 7], fellowship training [2, 7], radiologists’ enjoyment of interpreting mammograms [8], the balance of screening and diagnostic interpretations [4], and the influence of medical malpractice [9].…”

Mammographic Assessment of a Geographically Defined Population at a Mastology Referral Hospital in São Paulo Brazil

“…In a multicenter study, Taplin et al [20] reported a PPV1 of 4.1% and PPV2 of 38.8%. Duijm et al [21] observed a PPV2 of 37.4%. Rosenberg et al [22] observed a PPV1 of 4.8% and a PPV2 of 24.6%.…”