Geographic Matching

Payers are paired with providers via geographic matching. A payer-provider pair only enters the ROS if they have geographic overlap — or if either is "national."

Matching Logic

rate_object_space.sql — geographic join predicate

-- Payer-provider pairs are included when ANY of these conditions holds:
INNER JOIN ref_payers p
      ON (
  -- 1. Payer covers all states (national network)
  CONTAINS(p.network_state, 'NATIONAL')

  -- 2. Payer's state list includes the provider's state
  OR CONTAINS(p.network_state, pr.state)

  -- 3. Provider's CBSA falls within a state the payer covers
  OR pr.cbsa IN (
      SELECT cbsa_id
      FROM state_cbsa sc
      WHERE CONTAINS(p.network_state, sc.state_abbreviation)
  )

  -- 4. Provider explicitly accepts all national payers
  OR pr.national_payer_coverage = True
)

network_state is an ARRAY of state abbreviations (e.g., ['IL', 'WI', 'MN']) or ['NATIONAL']. CONTAINS checks whether the array includes the given string.

Matching Scenarios

Scenario	Matching rule	Example
National payer	CONTAINS(network_state, 'NATIONAL')	UHC, Aetna, Cigna
State-specific payer	CONTAINS(network_state, provider.state)	BCBS IL matches only IL providers
CBSA overlap	Provider's CBSA maps to a state the payer covers	Kaiser CA — provider's CBSA in CA, payer covers CA
National-coverage provider	national_payer_coverage = True	Quest Diagnostics, LabCorp
Exchange networks	Hospital only (except NYC Essential Plan)	ACA marketplace plans

Walkthrough — BCBS IL vs. UHC

How geographic matching differs for state vs. national payers

BCBS IL (state-specific): network_state = ['IL']. A provider in Springfield, IL (state = 'IL') passes the CONTAINS check. A provider in Indianapolis, IN fails — no ROID is minted for that pair.

UHC Choice Plus (national): network_state = ['NATIONAL']. The CONTAINS(network_state, 'NATIONAL') check passes for every provider regardless of state. All provider-payer combinations enter the ROS.

Quest Diagnostics (national-coverage provider): national_payer_coverage = True. Quest accepts all national payers. Even a state-specific payer whose state list doesn't include Quest's lab location will still be paired with Quest.

Geographic matching is the first and largest reduction step in ROS construction — typically eliminating ~80% of potential payer-provider pairs before code plausibility even runs.

note

network_state comes from network_mappings.py. When defining a state-specific network, set states explicitly:

('643', ['CHOICE PLUS STATE'], 'UHC Choice Plus IL', ['IL'])

National networks use [None] (which the pipeline converts to ['NATIONAL']).