Potter 2020.

Study characteristics
Methods	Prospective multi‐centre cohort July to December 2016 (iBRA), September 2016 to June 2017 (TeaM) Centres invovled in iBRA‐2 and TeaM trials, UK 2916 participants
Participants	Inclusion: Patients with invasive/in situ breast cancer undergoing therapeutic mammoplasty in participating centres of the TeaM study Only the subgroup of patients offered TM to avoid mastectomy was included in the present study Patients with invasive/in situ breast cancer undergoing mastectomy with or without breast reconstruction in participating centres of the iBRA
Interventions	Intervention: Volume displacement ‐ theraputic mammoplasty, (n = 376) Control: 1) Mastectomy, (n = 1532) 2) Mastectomy plus reconstruction, (n = 1008)
Outcomes	Primaryoutcomes: No outcomes of interest Secondaryoutcomes: Complications Time to adjuvant therapy Otheroutcomes: Margins and re‐excision only mentioned for the intervention group therefore not extracted
Notes	S.P. is a National Institute for Health Research (NIHR) Clinician Scientist (CS‐2016‐16‐019). T.R. has received support from the NIHR through a Doctoral Research Fellowship (DRF‐2014‐07‐079) and Academic Clinical Lectureship The TeaM study was funded by an Association of Breast Surgery research grant. This work was undertaken with the support of the NIHR Biomedical Research Centre at University Hospitals Bristol NHS Foundation Trust and the University of Bristol. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.