Advancements in the DRG system payment: an optimal volume/procedure mix model for the optimization of the reimbursement in Italian health care organization

In Italy, the reimbursement provided to health care organizations for medical and surgical procedures is based on the Diagnosis Related Group Weight (DRGW), which is an increasing function of the complexity of the procedures. This makes the reimbursement an upper unlimited function. This model does not include the relation of the volume with the complexity. The paper proposes a mathematical model for the optimization of the reimbursement by determining the optimal mix of volume/procedure, considering the relation volume/complexity and DRGW/complexity. The decreasing, linear, and increasing returns to scale have been defined, and the optimal solution found. The comparison of the model with the traditional approach shows that the proposed model helps the health care system to discern the quantity of the reimbursement to provide to health organizations, while the traditional approach, neglecting the relation between the volume and the complexity, can result in an overestimation of the reimbursement.