Table 5.

Comparison of Total Hospitalization Costs: The DPC System (Actual Billed Amounts) vs. Recalculated Using FFS (Reference Values)

Variables	(1) BMI < 30 (n = 60)	(2) BMI ≥ 30 (n = 42)	(2)—(1)	P
A: DPC (JPY) Mean ± SE	A1	A2	+ 34,142.9 ± 1,663	0.043
95%CI			116–6,713
B: FFC (JPY)a
Mean	B1	B2	+ 36,275.3 ± 1,767	0.040
95%CI			121–7,134
B-A (JPY)
Mean	– 6692.5 ± 19,861.6	– 18,139.5 ± 4242.5	– 11,450 ± 7640	0.137
95%CI			– 2,661—372

Total hospitalization costs in Japanese yen are determined using the Diagnosis Procedure Combination (DPC) and fee-for-service (FFS), a represents an estimated amount recalculated entirely under the FFS system. The actual values of A1, A2, B1, and B2 are confidential information; therefore, only the differences between the two groups are presented in the table. SE standard error, 95%CI 95% Confidence Interval, a represents an estimated amount recalculated entirely under the FFS system