[Effects of contemporaneous control of DRG-relevant coding by physicians].

Objective: In a prospective study we analysed the quality of ICD-coding in clinical everyday life of a department for internal medicine.

Methods: A skilled intern--the so-called DRG assistant--was temporarily released from clinical work. Over nine weeks he had to control all diagnoses contemporaneously that were ICD-coded by his colleagues on admission and discharge of their patients. The DRG-assistant had to ask for missing or correct implausible diagnoses, or inappropriate ICD-coding and with it also train his colleagues in appropriate coding. The effects of the DRG-assistant's correction of coding, on DRG-consistent grouping and on the potential financial loss or benefit generated by his work were recorded. After stoppage of this control in a subsequent phase of the study the effect of the absence of the DRG-assistant, the absence of reminders and coding control and the changes of the clinic's revenue were determined.

Results: Corrections of ICD-coding by the DRG-assistant alone caused a remarkable increase in case-mix-index (CMI). CMI's mean value increased from 1.76 to 1.84 and the clinic's revenue increased by 180 Euro per patient (a total of about 80,000 Euro in nine weeks). After the end of the control, the case-mix-index dropped within three weeks down to 1.14, corresponding with a potential loss of 1200 Euro per patient (assuming that patients' morbidity was the same over the time of the study). Coding corrections could not improve CMI in this situation.

Conclusion: Contemporaneous control of ICD-coding by physicians seems to be essential in DRG based accounting.