Primary care referral to a commercial provider for weight loss treatment versus standard care: a randomised controlled trial. by Jebb, SA, Ahern, A, Olson, A, Aston, L, Holzapfel, C, Stoll, J, Amann-Gassner, U, Simpson, A, Fuller, N, Pearson, S, Lau, N, Mander, A, Hauner, H, Caterson, I