Using additional baselines
The new baseline feature release will help our customers analyze in-line in Signal some of their most common questions:
- What is our rate as a percentage of Medicare?
- What is our inpatient base rate?
- What is our anesthesia conversion factor?
Default option
Overview
By default in Signal, you will see the following CMS-baseline columns if you click 'all columns' and scroll all the way to the right:
Baseline rate - This is effectively our best guess on what Medicare would pay for any given row of data (absent any override). See more notes on default CMS logic below on specifically how we bring this in.
Baseline schedule - This lets you know where we pulled what Medicare would pay (e.g., for hospital outpatient facility fees, we use the national outpatient prospective payment systems or OPPS payment amounts).
Relative to base - This is the rate posted in the row of data divided by the baseline rate.
Here's a quick video overview:
More notes on default CMS logic
Overall methodology:
Baseline rates in Serif Health TiC datasets are designed to be 1) consistent across rows taking
into account the billing code / code type, modifier, billing_class, and place of service code, and
2) derived from external, verifiable payment schedules from CMS.
When a row exists in the TiC data with billing metadata that does not align with a published
CMS schedule, the baseline value and baseline schedule fields are left blank.
Inpatient DRG > IPPS:
Medicare Inpatient payment rates are set per-facility and take into account many different
variables. This is at odds with the design for our ‘baseline’ rate field, as it would need to change
for every row of the data.
Instead, we use a single, national proxy value for each DRG derived from 2024 CMS tables that
only includes the adjusted labor and non labor operating amounts:
1. Sum the national adjusted operating standardized amounts for labor and non labor
portions from https://www.cms.gov/files/zip/fy2024-ipps-fr-table-1a-1e.zip to get a
national payment rate unit amount of $6497.77.
2. Multiply this rate times the 2024 DRG weight, obtained from
https://www.cms.gov/files/zip/fy2024-ipps-fr-table-5.zip, to get the baseline value for
each DRG.
Example: DRG 565 has a weight of .99994.
Our calculated baseline amount would be $6497.77 * .99994 = $6,493.87
Going through the Medicare PC pricer for CCN 360134, one day length of stay, with a covered
charge amount of $15,000, we see the sum of federal specific portions is 461.08 + 6007.91 =
6468.99, which is quite close to our baseline value.
However, as the PC pricer shows for this facility, uncompensated care amounts, medical
education subsidies, disproportionate share payments, and other adjustments would lead to an
expected payment amount for this claim at $8,819.19. As such, our baseline amount will tend to
skew lower than real-world payment amounts.
Outpatient Facility > OPPS:
Similar to inpatient, real-world outpatient payment rates for facilities are calculated by taking a
base payment amount, multiplying by a relative weight for the given APC or HCPCS code and
applying some scaling factors (both geographic and per-facility) to get to a calculated payment
value.
Serif Health only considers the national calculated payment amount for our baselines. We
gather national payment rate values directly from the 2024 OPPS Final Rule Addendum B.
https://www.cms.gov/license/ama?file=/files/zip/january-2024-opps-addendum-b-.zip
Whenever a TiC data row has a CPT or HCPCS code, billing_class = ‘institutional’, and a priced
OPPS amount is available in the table, it is carried through to the baseline rate field.
Example:
CPT/HCPCS code 10021 has a 2024 OPPS national payment amount of $379.92. This value is
directly used in any row with billing_code = ’10021’ and billing_class = ‘institutional’.
Outpatient Professional > PFS:
Professional fees are baselined to the CMS Physician Fee Schedule (PFS). PFS rates are published in a single payment amounts file, and are not further adjusted by any scaling factors other than site of service (facility vs. non-facility) and Medicare Administrative Contractor (MAC) locality.
For TiC data rows with CPT or HCPCS billing codes whose billing_class field is ‘professional’, the following baseline amount logic is used to set the baseline_rate and baseline_schedule fields:
1. The place_of_service_list field is used to determine whether nonfacility (POS code 11) or facility (POS codes 22, 21, 19) designation should apply. If codes for both place of service are listed in the data row, non-facility is assumed to be the correct designation.
2. If the data row has a populated npi_list, each NPI is crosswalked to its zip5 value using the latest release of NPPES, and each Zip5 is crosswalked to a MAC using the 2024 Zip5 to carrier locality file. The most common MAC value is considered to be the locality for the row. If a MAC locality cannot be determined, the national payment amount for locality 000000 is used.
3. The baseline_schedule will be set to PFS__S_<POS Value>_<Locality Value>, and the appropriate PFS schedule amount is entered in the baseline_rate field.
If no PFS payment amount exists for a given POS and Locality value, the baseline rate and baseline schedule fields will be left blank.
Examples: For a data row with CPT/HCPCS code 10021, site of service code 11 and no NPI list, the baseline will be reported as the 2024 national amount of $101.19 with schedule PFS_NONFACILITY_NPA. For data rows with CPT/HCPCS code 10021, site of service 11 that can be crosswalked to a MAC location of Indiana (0810200), the baseline amount will be reported as $93.94, schedule PFS_NONFACILITY_0810200. For data rows with CPT/HCPCS code 10021, site of service code 21 and no NPI list, the baseline will be reported as $54.26 with schedule PFS_FACILITY_NPA. For data rows with CPT/HCPCS code 10021, site of service 21 that can be crosswalked to a MAC location of Indiana (0810200), the baseline amount will be reported as $50.66, schedule PFS_FACILITY_0810200.
Overrides
Overview
If you need to adjust a CMS baseline for a specific analysis because the default logic offered does not meet your needs, we offer several options in Signal to choose from including:
Selecting any of these options re-sets the 'default' data that is presented in the baseline rate, baseline schedule, and relative to baseline columns to match whatever you chose.