> ## Documentation Index
> Fetch the complete documentation index at: https://docs.rcintell.com/llms.txt
> Use this file to discover all available pages before exploring further.

# L1: Physical location

> Resolve geographic and regulatory context from a CCN — GPCI values, MAC jurisdiction, Medicaid program, and timely filing rules

Layer 1 extracts the state code from the first two digits of a CCN and resolves all location-dependent billing context. This is the foundation layer — every other layer builds on it.

## How it works

A CCN's first two digits encode the state:

```
CCN: 170001
      ^^
      17 → Kansas (KS)
```

From the state, L1 resolves geographic adjustments (GPCI), the Medicare Administrative Contractor (MAC) that processes claims, the state Medicaid program, and filing deadlines.

## Request

```bash theme={null}
curl https://api-dev.rcintell.com/v1/knowledge/layers/170001/l1 \
  -H "X-API-Key: $RCI_API_KEY"
```

## Response

```json theme={null}
{
  "layer": "l1_location",
  "data": {
    "ccn": "170001",
    "state_code": "17",
    "state": "KS",
    "facility_type_code": "00",
    "facility_type": "Short-Term Acute Care Hospital",
    "gpci": {
      "pw_gpci": 1.0,
      "pe_gpci": 0.904,
      "mp_gpci": 0.504
    },
    "government_alignment": {
      "ab_mac": "Jurisdiction 5 (J5)",
      "ab_mac_contractor": "Wisconsin Physicians Service (WPS)",
      "contractor_id": "05202",
      "dme_mac": "Jurisdiction D (JD) - Noridian",
      "hh_mac": "Jurisdiction 15 (J15) - CGS Administrators"
    },
    "medicaid": {
      "program_name": "KanCare",
      "url": "https://portal.kmap-state-ks.us"
    },
    "timely_filing": "12 months from DOS",
    "balance_billing": "Follows No Surprises Act (federal)"
  }
}
```

## What L1 resolves

| Field                  | Description                                                                    | Used by                   |
| ---------------------- | ------------------------------------------------------------------------------ | ------------------------- |
| `gpci`                 | Geographic Practice Cost Index — adjusts Work, PE, and MP RVUs for local costs | L6 payment calculation    |
| `government_alignment` | MAC jurisdiction, contractor, and DME MAC assignments                          | Claim submission routing  |
| `medicaid`             | State Medicaid program name and portal URL                                     | L4 when payer is Medicaid |
| `timely_filing`        | Deadline for submitting claims to the state's payers                           | Billing teams             |
| `balance_billing`      | Whether balance billing is permitted                                           | Patient billing           |

## GPCI values explained

The Geographic Practice Cost Index adjusts Medicare's national RVU values for local cost differences:

| GPCI Component           | Measures                                           | Floor                   |
| ------------------------ | -------------------------------------------------- | ----------------------- |
| **Work GPCI** (pw\_gpci) | Physician labor costs relative to national average | 1.000 (cannot go below) |
| **PE GPCI** (pe\_gpci)   | Practice expense — rent, staff wages, equipment    | None                    |
| **MP GPCI** (mp\_gpci)   | Malpractice insurance premiums                     | None                    |

A GPCI of 1.0 means equal to the national average. Kansas has a Work GPCI floor of 1.000, a PE GPCI of 0.904 (9.6% below average), and a very low MP GPCI of 0.504 (malpractice is cheap in Kansas).

<Note>
  GPCI values are updated annually by CMS from the Physician Fee Schedule Relative Value Files. L6 uses these values automatically when calculating payment.
</Note>

## MAC jurisdictions

The Medicare Administrative Contractor (MAC) determines where claims are submitted and which LCD/NCD policies apply:

| MAC type    | Purpose                                                           |
| ----------- | ----------------------------------------------------------------- |
| **A/B MAC** | Processes Part A (institutional) and Part B (professional) claims |
| **DME MAC** | Processes Durable Medical Equipment claims                        |
| **HH MAC**  | Processes Home Health claims                                      |

Knowing your MAC matters because Local Coverage Determinations (LCDs) vary by jurisdiction. A service covered under one MAC may have different documentation requirements under another.

## State code reference

Common state codes used in CCNs:

| Code | State | Code | State | Code | State |
| ---- | ----- | ---- | ----- | ---- | ----- |
| 05   | CA    | 17   | KS    | 33   | NY    |
| 10   | FL    | 21   | MD    | 39   | PA    |
| 14   | IL    | 22   | MA    | 44   | TN    |
| 15   | IN    | 23   | MI    | 45   | TX    |

<Warning>
  State codes in CCNs are not the same as FIPS codes or postal abbreviations. State code `17` is Kansas (not Illinois). Always use the CCN parser to decode — don't assume.
</Warning>