This preliminary study determines whether the absolute amount of breast compression in mammography varies between and within practitioners.
Ethics approval was granted. 488 clients met the inclusion criteria. Clients were imaged by 14 practitioners. Collated data included Breast Imaging Reporting and Data System (BI-RADS) density, breast volume, compression and practitioner code.
A highly significant difference in mean compression used by different practitioners (p<0.0001 for each BI-RADS density) was demonstrated. Practitioners applied compression in one of three ways using either low, intermediate or high compression force, with no significant difference in mean compression within each group (p=0.99, p=0.70, p=0.54, respectively). Six practitioners showed a significant correlation (p<0.05) between compression and BI-RADS grade, with a tendency to apply less compression with increasing BI-RADS density. When compression was analysed by breast volume there was a wide variation in compression for a given volume. The general trend was the application of higher compression to larger breast volumes by all three practitioner groups.
This study presents an insight into practitioner variation of compression application in mammography. Three groups of practitioners were identified: those who used low, intermediate and high compression across the BI-RADS density grades. There was wide variation in compression for any given breast volume, with trends of higher compression demonstrated for increasing breast volumes. Collation of further studies will facilitate a new perspective on the analysis of practitioner, client and equipment variables in mammography imaging.
Advances in knowledge:
For the first time, it has been practically demonstrated that practitioners vary in the amount of compression applied to breast tissue during routine mammography.