Effect of probiotic use on antibiotic administration among care home residents: a randomized clinical trial by Butler, CC, Lau, M, Gillespie, D, Owen-Jones, E, Lown, M, Wootton, M, Calder, PC, Bayer, AJ, Moore, M, Little, P, Davies, J, Edwards, A, Shepherd, V, Hood, K, Hobbs, FDR, Davoudianfar, M, Rutter, H, Stanton, H, Lowe, R, Fuller, R, Francis, NA