Can software reach the system holding your record?

Where the chain breaks

Each step is a subset of the one above it. The candidate row sits outside the chain on purpose and is never added into coverage.

1. Active practitioners with an NPI

   227,917100%

   Everyone the NDH lists as practising in this state.

2. Has an active PractitionerRole

   100,37944%

   Without a role there is no organization, so no path to an endpoint at any confidence. This is the binding constraint. See the finding

   −127,538 lost at this step

3. Role names an organization that resolves

   93,30340.9%

   The reference points at an Organization that exists. See the finding

   −7,076 lost at this step

4. Organization carries an NPI

   93,30340.9%

   An organization NPI is what lets the org be joined to any other federal or vendor source.

5. Role names a location

   90,91839.9%

   The site the patient actually visited. No NDH Location carries an endpoint or a parent, so the place layer stops here.

   −2,385 lost at this step

6. Reaches a FHIR endpoint

   50,81222.3%

   Of these, 6,555 are deterministic (the NDH, or a vendor NPI on a URL listing 10 or fewer). Includes 14,656 reachable only after the vendor-published NPI fill (8,967 of them only through a URL whose vendor lists more than 10 NPIs, which is not deterministic), 26,173 only after name or brand resolution, and 8,076 only via the practitioner's CMS-enrolled group, of which 595 carry no PractitionerRole at all. The NDH alone reaches 1,907. See the finding

   −40,106 lost at this step

7. Name-matched endpoint candidate (not a linkage)outside the chain

   1,6930.7%

   An endpoint is published against an organization name that matches, but nothing deterministic connects them. This is where the large health systems land: the vendor names the brand, the NDH holds the practitioners under separate legal entities, and the NDH carries no hierarchy to bridge them. Triage material, not a directory linkage. See the finding

8. Endpoint attributed to an EHR vendor

   49,45621.7%

   The vendor is derived from the endpoint host and cross-checked against the file that published the URL. See the finding

Where the chain breaks, geographically

The same practitioners as the funnel above, placed by postal code. Colour is always a rate and never a count, so the map does not simply redraw where people live. Switch layers to change the encoding; the geometry stays put.

What established each link

Bands describe method, not quality. Green means the NDH itself carries the whole chain. Yellow means the last link came from a vendor-published NPI that matches an NDH organization: deterministic, but not the directory's own statement; since FHI-73 only on a URL listing 10 or fewer NPIs. Vendor list means the vendor publishes the organization's NPI beside a URL together with more than 10 other NPIs (a practice-wide or brand-wide list), so the NPI is published but the URL is not shown to serve that organization: counted as reaching an endpoint, not as deterministic. Resolved means the organization was matched to a vendor brand by curated alias, name or brand prefix plus state (H53); a curated alias outranks a vendor list, a name or brand match does not (resolved_by_tier splits it). Enrolled means only the practitioner's CMS-enrolled group reaches an endpoint. Red means the practitioner reaches an organization and stops. None means no organization at all. Candidate is weaker than red on evidence and is never counted as connectivity: an endpoint exists under a matching name, with nothing deterministic tying it to this organization.

Deterministic

1,907

Vendor NPI

4,648

Vendor NPI list

8,967

Alias, name or brand resolved

27,214

CMS-enrolled group

8,076

Name candidate

1,693

Stops at organization

41,588

No organization

133,824

Which EHR the reachable practitioners sit behind

Vendor is derived from the endpoint host and cross-checked against the file that published the URL. It covers only the 49,456 practitioners who reach an endpoint at all, so it describes the connected minority, not Pennsylvania’s EHR market.

The web, and the holes in it

The 50 largest systems, the endpoints any of their members reach, and the EHR vendor behind each endpoint. A system is filled only when the NDH or a vendor-published NPI reaches it (connected_deterministic); one reached only through a vendor NPI on a URL listing more than 10 NPIs, alias, name or brand match, or CMS enrollment is hollow with a blue ring and its links are dashed (tier on each link). Systems with no edge are the finding: they hold practitioners and nothing public connects them to a system that serves records. Since FHI-73 connected_deterministic excludes a system reached only through a vendor NPI list (see field_notes).

Health systems, and how we know

Health systems, best evidence first. `cms-ownership` groups come from CMS enrollment ownership data, which states ownership and names holding companies explicitly, but covers hospitals only. `nppes-parent` groups come from NPPES is_organization_subpart plus parent_organization_lbn: real, but sparse, sometimes stale, and sometimes a program rather than an owner. `brand-name` groups are inferred from the organization name and cover the rest. The directory's own OrganizationAffiliation resource was tried and rejected: see affiliation_graph below. Since FHI-73 each system's reach is reported per tier and per distinct clinician; see tiers and corrections.

A system reaching an endpoint is not a routing answer. Large systems publish several: UPMC has an Epic endpoint for its physicians and separate athenahealth endpoints for individual surgery centres. Every endpoint found in a system is listed with the member that carries it, and none of them is presented as the one serving a given practitioner.

Each system's reach is counted per distinct clinician at the strongest tier among the member organizations they hold roles at. ndh: the NDH attributes the endpoint to the member. vendor-npi: an EHR vendor publishes the member's NPI beside the endpoint, on a URL listing 10 or fewer NPIs. Both are deterministic. vendor-npi-list: the vendor publishes the member's NPI beside a URL listing more than 10 NPIs, a practice-wide or brand-wide list (athenahealth attaches one practice list to every department), so the URL is not shown to serve that member; inference, ranked below alias. alias: a curated, sourced legal-name-to-brand link (analysis/org_aliases.json); it outranks a vendor NPI list because it names this member, while a list names everyone in a practice. name-state and brand-state: the member's name or brand prefix matches a vendor brand in the same state (H53). Those three are inference. cms-enrollment-own-endpoint: the clinician's CMS-enrolled group resolves to an endpoint this system already reaches, or one on the system's own domain; enrollment that lands on another system's endpoint is not counted for this one. systems_reaching_an_endpoint and practitioners_in_a_system_that_reaches_an_endpoint count every tier; the _deterministic keys count the NDH and vendor-npi tiers only, and since FHI-73 vendor-npi means a URL listing 10 or fewer NPIs, so they are narrower than in earlier files (see field_notes). Counts marked * are inference: reached by a curated alias, vendor NPI on a practice-wide list, name or brand match, or CMS enrollment, not by the NDH or a vendor NPI on a URL listing 10 or fewer.

The work queue: who to fix first

Organizations with 25 or more practitioners that no method reaches: not by the NDH's own attribution, not by a vendor-published NPI, not by an exact name match. This is the work queue. Every row carries an NPPES link so each one can be checked against the primary source.

These 100 organizations hold 108,455 practitioners between them. For several of them a FHIR endpoint is already published by their EHR vendor, under the brand name rather than the legal entity name the directory carries. Nothing public connects the two.

Largest organizations, and what reaches them

Ranked by how many Pennsylvania practitioners name them. Each row shows its strongest route; an endpoint marked * is inference (a curated alias, a vendor NPI on a practice-wide list, or a name or brand match), not the NDH or a vendor NPI on a URL listing 10 or fewer. A candidate endpoint is shown in grey so it cannot be read as a resolved one.

Hospitals

Facility-level connectivity comes from the separate hospital audit, which starts from the CMS hospital list rather than from the directory. See the full hospital view.