Making casemix work for psychiatry.

Providers of mental health and substance abuse care cannot afford to ignore the existence of casemix descriptions of their services. As casemix comes to be the predominant language used to describe the products of hospital care, its use will inevitably impinge upon psychiatric services. The psychiatric components of the Australian national diagnosis-related groups classification 1 and 2 (AN-DRG 1 and 2) do not describe the relevant products with great accuracy. We review some possible reasons for this and the effects on the homogeneity of resource consumption of technical procedures, such as trimming of data sets, in the context of the current casemix system and that proposed for AN-DRG-3. The evolution of a casemix system which does justice to current and future psychiatric services will be a complex process. Some of the crucial areas are discussed. Clinicians involved in mental health and substance abuse care must continue to advocate for the resources and effort needed to improve casemix information in their area.