Participant characteristics in the Health in Vegetarians Consortium: a collaborative analysis of 11 prospective studies od Dunneram, Y, Lee, JY, Watling, CZ, Fraser, GE, Miles, F, Prabhakaran, D, Shridhar, K, Kondal, D, Mohan, V, Ali, MK, Narayan, KMV, Tandon, N, Tong, TYN, Chiu, THT, Greenwood, DC, Du, H, Chen, Z, Kakkoura, MG, Reeves, GK, Papier, K, Floud, S, Sinha, R, Liao, L, Loftfield, E, Cade, JE, Key, TJ, Perez-Cornago, A