A CASEMIX FOR MENTAL-HEALTH-SERVICES - THE DEVELOPMENT OF THE MENTAL-HEALTH AND SUBSTANCE-ABUSE COMPONENTS OF THE AUSTRALIAN NATIONAL DIAGNOSIS-RELATED GROUPS

Objective: To describe the development of the mental health and substa nce abuse sections of the version of the Australian casemix system, Au stralian national diagnosis-related groups 3 (AN-DRG 3), released in J uly 1995. Method: The guiding principles and data sources used to cons truct the mental health and substance abuse components of AN-DRG 3 are described by the group who undertook that task, The group used data s ets of patients separating from hospitals throughout Australia, and fr om hospitals in South Australia, to examine the capacity of existing a nd revised diagnosis-related groups (DRGs) to predict patients' length s of hospital stay, They also reviewed the lists of conditions allowed as complicating and comorbid conditions within the AN-DRG system.Resu lts: A variety of recommendations were made including: moving organic mental disorder DRGs to a neuroscience area of the AN-DRG; completely reorganising the mental health section of the casemix; creating a numb er of narrowly defined DRGs covering areas such as schizophrenia, majo r affective disorders, anxiety disorders and eating disorders, while a llowing for a limited number of more heterogenous DRGs; and simplifyin g substance abuse DRGs into groups covering alcohol and other substanc es, and differentiating intoxication and withdrawal from abuse and dep endency. Conclusions: A casemix dialect based on clinical diagnosis, w hich describes mental health and substance abuse problems in terms whi ch should be familiar to clinicians, has been developed, Its applicati ons and limitations are briefly discussed.