Study protocol for a pragmatic randomised controlled trial of comparing enhanced acceptance and commitment therapy plus (+) added to usual aftercare versus usual aftercare only, in... by Khan, I, Taylor, SJC, Robinson, C, Moschopoulou, E, McCrone, P, Bourke, L, Thaha, M, Bhui, K, Rosario, D, Ridge, D, Donovan, S, Korszun, A, Little, P, Morgan, A, Quentin, O, Roylance, R, White, P, Chalder, T