Technical efficiency in the clinical management of critically ill patients.

The purpose of this paper is to obtain empirical measures of performance in the management of critical patients treated in intensive care units (ICUs) and to evaluate the factors associated with performance, in a two stage approach. In the first stage, this paper uses an extended version of Data Envelopment Analysis (non-discretionary and categorical variables, and weight constraints under consideration) to obtain measures of technical efficiency in the treatment of 993 critical care patients in intensive care units in Catalonia (Spain) in 1991-92. The model incorporates accurate individual measures of illness severity from Mortality Probability Models (MPM II0) and quality outcome measures in the input-output set to obtain non-biased efficiency measures. In the second stage, a loglinear regression model is applied to test a number of hypothesis about the role of different environmental factors--such as ownership, market structure, dimension, internal organization, diagnostic, mortality risk, etc.--to explain differences in the efficiency scores.