This is an abridged version of the Classic Article by E.A. Codman, A Study in Hospital Efficiency: As Demonstrated by the Case Report of the First Five Years of a Private Hospital. The full article is available as supplemental material for the abridged version in the online version of CORR (R). An accompanying biographical sketch of E.A. Codman is available at DOI 10.1007/s11999-012-2750-4. The Classic Article is A (c) 1918 and is reprinted courtesy of Thomas Todd Co. from E.A. Codman. A Study in Hospital Efficiency: As Demonstrated by the Case Report of the First Five Years of a Private Hospital. Boston: Thomas Todd Co.; 1918: 4-10,108,162.