Breast imaging readers' performance in the PERFORMS test-set based assessment scheme within the MyPeBS international randomised study.

Purpose: A survey conducted by the European Society of Breast Imaging (EUSOBI) in 2023 revealed significant variations in Quality Assurance (QA) practices across Europe. The UK encourages regular performance monitoring for screen readers. This study aimed to assess the variability in diagnostic performance among readers participating in a wider prospective randomised trial across multiple countries.

Method: In this retrospective multinational study, breast imaging readers from the MyPeBS clinical trial examined a test set of 40 challenging breast screening cases using the PERFORMS software, from March 2021 to February 2022. The challenging set, enriched with biopsy-proven cancers, aimed to differentiate readers by their level of diagnostic performance. Cancer detection and correct return to screen rates were calculated for each participant.

Results: A total of 110 readers from 6 countries completed the PERFORMS test set, while 88 also completed an accompanying questionnaire collecting information about their breast screening work and experience. The study revealed variability in cancer detection rates (M = 73.6 %, SD = 19.7 %, range 0.0 %-100.0 %) and correct return to screen rates (M = 79.7 %, SD = 10.5 %, range 46.4 %-100.0 %). Outliers with extremely low cancer detection (2.7 % of participants) and correct return to screen rates (1.8 % of participants) were also identified.

Conclusions: Breast imaging readers' performance in test set-based assessments like PERFORMS can reflect real-world screening proficiency. The presence of outlier readers with low diagnostic performance on the test highlights the need for double reading and for standardised QA protocols to ensure patient safety and service efficiency.