PRospective Evaluation of natriuretic peptide-based reFERral of patients with chronic heart failure in primary care (PREFER): a real-world study by Hobbs, FR, Hussain, RI, Vitale, C, Pinto, YM, Bueno, H, Lequeux, B, Pauschinger, M, Obermeier, M, Ferber, PC, Gustafsson, F