[A DRG/PPS simulation in the medical care of tuberculosis].

Purpose: To study the expected usefulness of the introduction of the DRG-PPS (Diagnosis-Related Group/Prospective Payment System, in which an insurer pays a fixed medical fee per hospitalization) into the current medical care of tuberculosis (TB) in Japan.

Method: The medical fees were reviewed for all TB inpatients at 19 hospitals under the National Hospital Organization who were discharged in either June 2007 or February 2008. The sum of the fixed fee by the DRG was assumed based on the bivariate regression analysis of each patient's hospital days and his or her total actual fees during the hospital stay under the current (fee for care) system, since it was difficult to directly calculate the daily fees for every patient that would be the basis of DRG-PPS.

Results: Linear regression analysis estimated that the medical fees (including fees for the medical examinations and the treatments) for a hospital stay of 60 days, which is the standard for TB treatment, was 1,192,470 yen (19,870 yen per person per day) in June 2007, and 1,167,600 yen (19,460 yen per person per day) in February 2008.

Discussion: If we assume an average medical fee of about Y1.1-1.2 million yen for the standard hospital care of TB, the economic balance of the hospitals is negative, with a deficit of 0.6-0.7 million yen, given the estimated expenses of 1.8 million yen (i.e., 30,000 yen per person per day x 60 days).

Conclusion: If the DRG-PPS is to be implemented based on the current medical fee rating system, the hospital administrators could not accept its introduction to the TB medical care service as it is, because it may undermine the economic management of hospitals.