This is one component of the total amount that is payable on prospective payment system (PPS) claims, and reflects the DSH (disproportionate share hospital) payments for operating expenses (such as labor) for the claim.
There are two types of DSH amounts that may be payable for many PPS claims; the other type of DSH payment is for the DSH capital amount (variable called CLM_PPS_CPTL_DSPRPRTNT_SHR_AMT).
Both operating and capital DSH payments are components of the PPS, as well as numerous other factors.
Medicare payments are described in detail in a series of Medicare Payment Advisory Commission (MedPAC) documents called “Payment Basics” (see: http://www.medpac.gov/payment_basics.cfm).
Also in the Medicare Learning Network (MLN) “Payment System Fact Sheet Series” (see: http://www.cms.gov/Outreach-and-Education/Medicare-Learning-NetworkMLN/MLNProducts/MLN-Publications.html).
DERIVATION RULES: If there is a value code '18' (i.e., in the Value Code File, if the VAL_CD='18') then this dollar amount (VAL_AMT) is used to populate this field."