Statistical analysis plan for the PRO B study: open-label, superiority randomised controlled trial of alarm-based patient-reported outcome monitoring in patients with metastatic breast cancer.

"Declarations Ethics approval and consent to participateThe study is conducted in accordance with the Helsinki Declaration and ICH guidelines to Good Clinical Practice (GCP). The PRO B study has been approved by the institutional review board of Charité—Universitätsmedizin Berlin (application number: EA1/318/20) and has been individually adapted for all participating study sites. Participation is voluntary, and written informed consent is mandatory prior to enrollment. It will be obtained by the treating physician during routine clinical visits. Consent for publicationNot applicable. Competing interestsThe authors declare that they have no competing interests. Competing interests The authors declare that they have no competing interests."

"Funding Open Access funding enabled and organized by Projekt DEAL. The study is funded by a public grant from the Innovation Committee of the Federal Joint Committee (“Innovationsauschuss des Gemeinsamen Bundesausschusses”, grant number 01NVF19013). The funder has no further role in the writing of this statistical analysis plan."

"Trial registration DRKS (German Clinical Trials Register) DRKS00024015. Registered on February 15, 2021."