Over the past 25 years much effort has been put into the research of the relationship between neuropsychiatric disorders and the concentrations of CSF-monoamine metabolites. Most of this research has beenfocused on the relation between CSF-concentrations of 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) and specific symptomatological entities, particularly schizophrenia, Alzheimer's dementia and endogenous depression. It appeared that specific relations between diseases and CSF-concentrations of monoamine metabolites cannot be longer maintained and that a more functional psychopathology should be considered as the future research strategy.

Objectives: Excessive use of laboratory diagnostics has been common. This study aimed to evaluate whether clinical decision rules for the use of liquor diagnostics would enable cost containment without affecting medical care.

Methods: This was a single-center, retrospective, cost-minimization study based on the records of all 16,319 patients hospitalized and discharged at a Neurology Clinic in Austria between 2004 and 2006. Cost of liquor diagnostics, discharge diagnosis, duration of hospital stay, and mortality were compared along the line before, during, and after implementation of decision rules in mid-2005.

Results: There were no significant changes in patient characteristics over time, not in the diagnoses at discharge, nor in the percentage of patients undergoing liquor diagnostics. The average number of tests per patient significantly decreased. Standard tests largely replaced serological tests for infections, regardless of diagnosis. Annual costs for liquor diagnostics decreased by 32.9 percent. Overall, the duration of hospital stay and mortality significantly decreased as well; however, differences were not significant for any single diagnosis-related group.

Conclusions: Diagnostic algorithms may allow cost containment without affecting medical care.