Registration and randomisation pathway
DCIS
Enrolment to LORIS was a two-step process; registration followed by randomisation (see Fig. Registration and randomisation pathwayWomen were eligible for randomisation into LORIS if a diagnosis of low-risk DICS was confirmed by central review. Those eligible for LORIS were consented and randomised 1:1 to either surgery, the contemporary standard treatment for DCIS, or active monitoring, i.e. annual mammograms for 10 years. Women who declined randomisation were invited to complete the Clinical Trials Questionnaire (CTQ), a widely used validated measure of reasons why patients agree or decline entry into RCTs [