A framework for longitudinal latent factor modelling of treatment response in clinical trials with applications to Psoriatic Arthritis and Rheumatoid Arthritis by Falck, F, Zhu, X, Ghalebikesabi, S, Kormaksson, M, Vandemeulebroecke, M, Zhang, C, Martin, M, Gardiner, S, Hei Kwok, C, West, D, Santos, L, Tian, C, Readie, A, Ligozio, G, Gandhi, K, Nichols, T, Mallon, A-M, Kelly, L, Ohlssen, D, Nicholson, G