Development of a primary care screening algorithm for the early detection of patients at risk of primary antibody deficiency.

"Declarations Ethics approval and consent to participateEthical approval for this study was received from the Medical Research Ethics Committee Utrecht, protocol number 19-748. Patients with primary antibody deficiency of the University Medical Center Utrecht provided written informed consent. The need for informed consent for the group-level primary care data of the Julius General Practitioner’s Network was waived, as this only concerns meta-level data (e.g. means and medians). Consent for publicationNot applicable. Competing interestsHL and JM received consulting fees for AdBoards with Takeda Pharmaceuticals. RB received personal fees from Takeda Pharmaceuticals. Competing interests HL and JM received consulting fees for AdBoards with Takeda Pharmaceuticals. RB received personal fees from Takeda Pharmaceuticals."

"Funding This study was funded by Takeda Pharmaceuticals."

"Trial registration The consecutive prospective study is registered at clinicaltrials.gov under NCT05310604"