J Korean Soc Radiol.  2010 Oct;63(4):383-389.

Interobserver Variability in the Interpretation of Microcalcifications in Digital Magnification Mammographies

• Jeon SJ
• Kim MJ
• Kim EK
• Son EJ
• Youk JH
• Kwak JY
• Choi SH

Abstract

PURPOSE
To analyze the interobserver variability of radiologists in their description and final assessment categories of microcalcifications in digital magnification mammographies.
MATERIALS AND METHODS
From 2005 to 2006, five radiologists analyzed 66 lesion microcalcifications in 65 patients on digital magnification mammographies using a blind method and including 40 benign and 26 malignant lesions. Each observer evaluated the microcalfication morphology, distribution, and BIRADS(R) category. Using the kappa value, the degree of interobserver agreement was calculated and the rate of malignancy was assessed.
RESULTS
The mean kappa value for microcalcification morphology was 0.19, which was considered to be moderate agreement for the microcalcification distribution (k: 0.54). The overall rate of malignancy was 39% for microcalcification morphology and distribution. Among them, amorphous microcalcifications showed the lowest rate of malignancy (17%). The mean kappa value for the final assessment categories of BI-RADS(R) was 0.29 and the mean rate of malignancy was 39%.
CONCLUSION
Although there was slight interobserver variability, according to each of the descriptors, the general interobserver agreement in interpretation of microcalcification on digital magnification mammogram was slight to moderate. To improve interobserver agreement for the interpretation of microcalcifications, proper image quality control, standardization of criteria, and proper training of radiologists are needed.

MeSH Terms

Calcinosis
Humans
Mammography
Observer Variation
Quality Control
Subject Headings

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