A retrospective cohort study comparing differences in 30-day mortality among critically ill patients aged ? 70 years treated in European tax-based healthcare systems (THS) versus social health insurance systems - Wernly, Bernhard; Flaatten, Hans; Beil, Michael; Fjølner, Jesper; Bruno, Raphael Romano; Artigas, Antonio; Pinto, Bernardo Bollen; Schefold, Joerg C.; Kelm, Malte; Sigal, Sviri; van Heerden, Peter Vernon; Szczeklik, Wojciech; et al. (2022)