Related Experiment Video
Updated: Aug 15, 2026

Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
Published on: August 30, 2013
Phase-wise comparison of positioning time between novices and experts in mammography: A pilot study
A Yagahara1, M Kawai2, H Yamashina3
1Department of Radiological Technology, Hokkaido University of Science, 7-Jo 15-4-1 Maeda, Teine, Sapporo, 006-8585, Japan; Faculty of Health Sciences, Hokkaido University, N12-W5, Kitaku, Sapporo, 060-0812, Japan.
Introduction:
High-quality mammography depends on radiological technologists' technique. However, key procedural know-how is often tacit and difficult to articulate, making it challenging for novices to reproduce expert performance. This pilot study quantified timing differences between novice and expert operators during mediolateral oblique (MLO) mammography positioning.
Methods:
Left MLO positioning was performed on a mammography unit by three expert technologists and two novice students. Five volunteers without mammography experience acted as simulated patients. The procedure was recorded using three cameras. Two raters identified phase boundaries and extracted time from breast lifting and pulling to completion of compression. The procedure was divided into four phases: (1) breast lifting and pulling, (2) breast holding, (3) breast flattening, and (4) breast compression. Results are presented as individual values and medians (range). Effect sizes were expressed as median differences and ratios with 95% bootstrap intervals.
Results:
Total positioning time was shorter for novices than experts (median 5.8 s vs 15.6 s), with a median difference of 9.8 s (95% bootstrap interval 2.3-11.7) and a median ratio of 2.7 (1.3-4.0). Phase-wise analysis showed no consistent difference in phase (1) (median difference -0.5 s; -1.6 to 2.1). Experts spent longer in phases (2)-(4): breast holding, 1.8 s (0.8-2.2); flattening, 3.6 s (2.5-3.9); and compression, 2.8 s (0.6-5.7).
Conclusion:
Experts spent longer than novices during MLO positioning, particularly during breast holding, breast flattening, and breast compression. Timing analysis may support training and clarify how novices develop proficiency.
Implications For Practice:
Shorter procedural time may reflect reduced checking behavior or immature attentional allocation rather than easier performance. Instruction should target these phases and make goals, checking behaviors, and movement strategies explicit.

