Conflict of interest: C. Macaluso has nothing to disclose. Conflict of interest: J. Maritano Furcada has nothing to disclose. Conflict of interest: O. Alzaher has nothing to disclose. Conflict of interest: R. Chaube has nothing to disclose. Conflict of interest: F. Chua has nothing to disclose. Conflict of interest: A.U. Wells reports speaker's and consultancy fees from Intermune Roche, Boehringer Ingelheim and Bayer. Conflict of interest: T.M. Maher has, via his institution, received industry-academic funding from GlaxoSmithKline R&D and UCB, and has received consultancy or speaker's fees from Apellis, AstraZeneca, aTyr Pharma, Bayer, Biogen Idec, Boehringer Ingelheim, Galapagos, GlaxoSmithKline R&D, ProMetic, Roche, Sanumed and UCB. Conflict of interest: P.M. George reports receiving honoraria and speaker's fees from Roche Pharmaceuticals and Boehringer Ingelheim, outside the submitted work. Conflict of interest: E.A. Renzoni has received speaker's fees from Boehringer Ingelheim, Roche and Mundipharma. Conflict of interest: P.L. Molyneaux has nothing to disclose.