Mammographic interpretive volume and diagnostic mammogram interpretation performance in community practice

Area of Science:

• Radiology
• Medical Imaging
• Breast Cancer Screening

Background:

• Radiologist interpretive volume is a critical factor in diagnostic accuracy.
• Understanding the relationship between mammography volume and performance is essential for quality assurance.
• Existing regulations may not adequately differentiate between screening and diagnostic mammography volumes.

Purpose of the Study:

• To investigate the association between radiologist interpretive volume and diagnostic mammography performance.
• To analyze how different volume measures (annual diagnostic, screening, total, diagnostic focus) affect sensitivity and false-positive rates.
• To stratify analyses by imaging indication: additional imaging post-screening or evaluation of breast concerns.

Main Methods:

• Retrospective analysis of 117,136 diagnostic mammograms interpreted by 107 radiologists (2002-2006).
• Logistic regression used to assess the impact of four volume measures on sensitivity, false-positive rates, and cancer detection.
• Analyses stratified by indication: post-screening additional imaging versus breast concern evaluation.

Main Results:

• Diagnostic volume showed a significant association with sensitivity, peaking around 1000 mammograms annually.
• Diagnostic focus (percentage of diagnostic mammograms) was linked to false-positive rates, with optimal performance around 20% focus.
• Neither total interpretive volume nor screening volume consistently correlated with diagnostic performance metrics.

Conclusions:

• The relationship between interpretive volume and diagnostic mammography performance is complex and multifaceted.
• Diagnostic interpretive volume appears to be a key factor in establishing abnormality thresholds for diagnostic mammograms.
• Current volume regulations, which do not differentiate between screening and diagnostic mammography, may require revision.