OPTIMA: a prospective randomised trial to validate the predictive utility and cost-effectiveness of gene expression test-directed chemotherapy decisions. Issue 11 (November 2016) - Stein, Robert; Makris, Andreas; Hughes-Davies, Luke; Macpherson, Iain; Marshall, Andrea; Campbell, Amy; Hall, Peter; Cameron, David; Earl, Helena; Francis, Adele; Pinder, Sarah; Poole, Christopher; et al.