Note: Funding Information: The SYMPHONY consortium, which aims to orchestrate personalized treatment in patients with bleeding disorders, is a unique collaboration between patients, health care professionals and translational and fundamental researchers specialized in inherited bleeding disorders, as well as experts from multiple disciplines. SYMPHONY aims to identify best treatment choice for each individual based on bleeding phenotype. In order to achieve this goal, workpackages have been organized according to three themes e.g. Diagnostics (workpackage 3&4), Treatment (workpackages 5–9) and Fundamental Research (workpackages 10–12). This research received funding from the Netherlands Organization for Scientific Research (NWO) in the framework of the NWA-ORC Call grant agreement NWA.1160.18.038. Principal investigator: Dr M.H. Cnossen. Beneficiaries of the SYMPHONY consortium: Erasmus MC – Sophia Children's Hospital, University Medical Center Rotterdam, project leadership and coordination; Sanquin Diagnostics; Sanquin Research; Amsterdam University Medical Centers; University Medical Center Groningen; University Medical Center Utrecht; Leiden University Medical Center; Radboud University Medical Center; Netherlands Society of Hemophilia Patients (NVHP); Netherlands Society for Thrombosis and Hemostasis (NVTH); Bayer B.V., CSL Behring B.V., Swedish Orphan Biovitrum (Belgium) BVBA/SPRL. The Dutch research group for PROMIS implementation in inherited bleeding disorders aims to research the feasibility, reliability and validity of Dutch PROMIS item banks in children and adults with inherited bleeding disorders. We would like to thank our colleagues Marjolein Peters, Michiel Coppens, Hester F. Lingsma, Marieke J.H.A. Kruip, Lize F.D. van Vulpen & Tessa C.M. van Gastel for their contribution to the Dutch research group for PROMIS implementation in inherited bleeding disorders. Funding Information: The SYMPHONY consortium, which aims to orchestrate personalized treatment in patients with bleeding disorders, is a unique collaboration between patients, health care professionals and translational and fundamental researchers specialized in inherited bleeding disorders, as well as experts from multiple disciplines. SYMPHONY aims to identify best treatment choice for each individual based on bleeding phenotype. In order to achieve this goal, workpackages have been organized according to three themes e.g. Diagnostics (workpackage 3&4), Treatment (workpackages 5–9) and Fundamental Research (workpackages 10–12). This research received funding from the Netherlands Organization for Scientific Research (NWO) in the framework of the NWA‐ORC Call grant agreement NWA.1160.18.038. Principal investigator: Dr M.H. Cnossen. Beneficiaries of the SYMPHONY consortium: Erasmus MC – Sophia Children's Hospital, University Medical Center Rotterdam, project leadership and coordination; Sanquin Diagnostics; Sanquin Research; Amsterdam University Medical Centers; University Medical Center Groningen; University Medical Center Utrecht; Leiden University Medical Center; Radboud University Medical Center; Netherlands Society of Hemophilia Patients (NVHP); Netherlands Society for Thrombosis and Hemostasis (NVTH); Bayer B.V., CSL Behring B.V., Swedish Orphan Biovitrum (Belgium) BVBA/SPRL.