ASP-RCM Skilled nursing and long-term care billing.

Physical therapy, occupational therapy, speech-language pathology, nursing, and non-therapy ancillary. Each is classified into its own case-mix group and priced separately, then added to a sixth non-case-mix component that covers room, board, and administrative cost. PT has 16 groups, OT has 16, SLP has 12, nursing has 25, and NTA has 6. The five case-mix groups are what the five-character HIPPS code on the claim encodes, with PT and OT sharing the first character and the fifth character identifying the assessment used.

Two components change value as the stay ages. PT and OT are paid at an adjustment factor of 1.00 for days 1 through 20, then the factor steps down by 0.02 every seven days, reaching 0.76 for days 98 through 100. NTA runs the opposite way: an adjustment factor of 3.00 applies to days 1 through 3 to front-load the cost of admission medications and supplies, then drops to 1.00 for days 4 through 100. SLP, nursing, and the non-case-mix component carry no variable per diem adjustment and stay flat for the whole stay.

The 5-day PPS assessment sets the HIPPS code that prices every covered Part A day of the stay unless an Interim Payment Assessment replaces it. One assessment window, with an assessment reference date in the first eight days, determines up to 100 days of payment across five components at once. An understated Section GG function score, a missing swallowing or mechanically altered diet item, an uncoded depression screen, or a comorbidity that never made it out of the chart is not a one-day error. It repeats every day until discharge.

During a covered Part A stay the SNF bundle covers nearly everything, and the exceptions are enumerated at 42 CFR 411.15(p)(2): physicians' professional services and the services of physician assistants, nurse practitioners, clinical nurse specialists, nurse-midwives, qualified psychologists, and certified registered nurse anesthetists, plus dialysis and related supplies and transport, erythropoietin for dialysis patients, hospice care for the terminal condition, ambulance for the initial admission and final discharge, certain chemotherapy items and their administration, radioisotope services, customized prosthetic devices, blood clotting factors, and rural health clinic and federally qualified health center services. CMS also publishes an annual major categories file covering hospital outpatient services that a SNF cannot furnish, including CT, MRI, cardiac catheterization, radiation therapy, and angiography. Therapy is never on the excluded list.

Medicare Part A covers up to 100 days of skilled care in a benefit period. When a resident exhausts those days, or drops below a skilled level of care while remaining in the building, the stay does not stop generating billable services. Therapy and certain ancillary services move to Part B. A facility that only runs a Part A billing workflow stops billing on the day the benefit runs out, and the resident days that follow become invisible. The exhaust date is knowable on the day of admission, so every resident should carry a benefit day count and a projected exhaust date from the first covered day.

An MA plan is not required to pay a PDPM per diem. Most pay a negotiated rate structure, often level-of-care tiers or a flat per diem, and they manage the stay with prior authorization and concurrent review rather than an assessment. That produces two different operating models in the same building: fee-for-service days are won on MDS accuracy, Medicare Advantage days are won on authorization currency. Since the contract year 2024 Medicare Advantage final rule at 88 FR 22120, MA plans must follow traditional Medicare coverage criteria and may use internal criteria only where Medicare criteria are not fully established, which makes the stated basis of a denial an auditable object rather than a matter of plan discretion.