[The correct mammographic positioning in breast cancer screening]

To compare the positioning quality of mammograms produced by new (NRs) versus experienced (ERs) screening radiographers in the Dutch breast cancer screening programme.

Retrospective study.

NRs must successfully complete an education programme before being allowed to start work in Dutch screening practice. This education programme consists of a theoretical component, a practical component and a final practical examination, including a portfolio review. Furthermore, each unit undergoes an audit once every three years. During the audit, mammograms produced by ERs in the unit are assessed on the basis of criteria relating to the positioning of the breast. In this retrospective study, we analysed 13,520 images from portfolios (NRs) and 14,896 images from audits (ERs) on the basis of pre-specified quality criteria, e.g. depiction of the pectoral muscle.

Positioning quality was significantly better by NRs than ERs (CC views: 97% versus 86% adequate, p<0.01; MLO views: 92% versus 84% adequate, p<0.01). NRs scored better for most of the CC criteria but had more difficulty with for example the inframammary angle in MLO views than ERs. Overall, the mammograms from NRs were more often considered adequate, because their errors were less serious.

NRs perform better than ERs in terms of quality of positioning technique. These results stress the need for continuous monitoring of and feedback into the Dutch breast cancer screening programme to maintain high-quality screening mammography.