“…reported that the non‐elective admission rate was higher in very‐low‐volume hospitals than in very‐high‐volume hospitals (51.4% vs 29.7%), and that this discrepancy was possibly associated with a difference in mortality rates (13.0% vs 8.7%). A significant correlation between hospital volume and postoperative mortality was also observed in six studies in the USA 16, 17, 18, 19, 20, 21 and three studies in Europe 22, 23, 24. Among eight other large‐scale studies, only one could not show a significant relationship between higher hospital volume and lower hospital mortality, but the absolute difference in mortality between low‐ and high‐volume hospitals was greater than 1% (8.7% vs 6.9%) 25…”