Final answer:
The shift from PPS to DRG in inpatient care changed the billing mechanism to a fixed payment system based on diagnosis, promoting cost efficiency but raising quality of care concerns due to potential premature discharges.
Step-by-step explanation:
When inpatient care shifted from the Prospective Payment System (PPS) to Diagnosis-Related Groups (DRG), there was a fundamental change in the mechanism for hospital billing and payments. Under the DRG system, hospitals began receiving a fixed payment amount for inpatient care based on the patient's diagnosis and predetermined rates, rather than being reimbursed for each service provided as it was under the PPS. This shift emphasized cost efficiency and incentivized hospitals to control their inpatient care costs. However, it also raised concerns about quality of care, as hospitals might discharge patients prematurely to minimize costs. DRG implementation was significant in driving hospitals to be more economically responsible, although it was also faced with the challenge of maintaining high-quality patient care.