title: Productivity growth, case mix and optimal size of hospitals. A 16-year study of the Norwegian hospital sector.
abstract: OBJECTIVE
  This paper analyses productivity growth in the Norwegian hospital sector over a period of 16 years, 1999-2014. This period was characterized by a large ownership reform with subsequent hospital reorganizations and mergers. We describe how technological change, technical productivity, scale efficiency and the estimated optimal size of hospitals have evolved during this period.
  
  
  METHODS
  Hospital admissions were grouped into diagnosis-related groups using a fixed-grouper logic. Four composite outputs were defined and inputs were measured as operating costs. Productivity and efficiency were estimated with bootstrapped data envelopment analyses.
  
  
  RESULTS
  Mean productivity increased by 24.6% points from 1999 to 2014, an average annual change of 1.5%. There was a substantial growth in productivity and hospital size following the ownership reform. After the reform (2003-2014), average annual growth was <0.5%. There was no evidence of technical change. Estimated optimal size was smaller than the actual size of most hospitals, yet scale efficiency was high even after hospital mergers. However, the later hospital mergers have not been followed by similar productivity growth as around time of the reform.
  
  
  CONCLUSIONS
  This study addresses the issues of both cross-sectional and longitudinal comparability of case mix between hospitals, and thus provides a framework for future studies. The study adds to the discussion on optimal hospital size.
authors.affiliation: Norwegian University of Science and Technology, Department of Public Health and Nursing, PO Box 8905, 7491 Trondheim, Norway; SINTEF Technology and Society, Department of Health Research, PO Box 4760, Sluppen, 7465 Trondheim, Norway. Electronic address: kjartan.s.anthun@sintef.no.
authors.forename: Kjartan Sarheim
authors.initials: KS
authors.lastname: Anthun
authors.affiliation: The Ragnar Frisch Centre for Economic Research, Gaustadalléen 21, 0349 Oslo, Norway. Electronic address: sverre.kittelsen@frisch.uio.no.
authors.forename: Sverre Andreas Campbell
authors.initials: SA
authors.lastname: Kittelsen
authors.affiliation: Norwegian University of Science and Technology, Department of Public Health and Nursing, PO Box 8905, 7491 Trondheim, Norway. Electronic address: jon.magnussen@ntnu.no.
authors.forename: Jon
authors.initials: J
authors.lastname: Magnussen
mesh_terms: D003430:Cross-Sectional Studies; D003953:Diagnosis-Related Groups / Q000191:economics*; D017598:Efficiency, Organizational / Q000706:statistics & numerical data*; D006276:Health Facility Size / Q000191:economics*; D006302:Health Services Research; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D062069:Inventions / Q000706:statistics & numerical data; D009664:Norway; D010067:Ownership; D013222:State Medicine / Q000191:economics
keywords: Diagnosis-related groups; Health care reform; Health services research; Healthcare financing; Hospital economics; Organizational efficiency