Case Mix Index
The Case Mix Index (abbreviation CMI, Syn. Case severity index in the DRG system) describes the average severity of patient cases for a certain period of time, measured on a scale that corresponds to the total resource expenditure. It represents a measure of the relative economic resource expenditure of all treated hospital cases. The CMI is particularly important in medical-economic patient classification systems such as Diagnosis Related Groups (DRG).
The case mix index is calculated for a calendar year by adding the relative weights (cost weight, CW) of each patient case [sum = case mix (CM)] and then dividing by the number of cases. The case mix is the sum of the relative weights billed by a hospital in a certain period.
Restriction
The CMI only reflects average ratios and, as a mean value, says nothing about the distribution of the degrees of severity.
The CMI is a relative comparison criterion for the cost structure of a hospital, but not an absolute measure of efficiency.
Individual evidence
- ↑ Bernhard Rochell: Current status of the implementation of § 17 b KHG (2000) . In: www.imbi.uni-freiburg.de, here online ( Memento of the original from June 4, 2008 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. ; last viewed on Jan. 11, 2008
