Utilising primary care electronic health records to deliver the ALABAMA randomised controlled trial of penicillin allergy assessment by Ahmed, S, Fielding, J, Porter, CE, Armitage, KF, Wanat, M, Bates, C, Engonidou, L, West, RM, Yu, L, Galal, U, Howard, P, Butler, CC, Savic, S, Boards, J, Tonkin-Crine, S, Parry, J, Pavitt, SA, Sandoe, JT