Findings
Pre-registered audit findings on the CMS National Provider Directory.
Each finding lists its null hypothesis, denominator, and data source before results drop. Methodology: /methodology.
Resources processed
27.2M
NPIs flagged
0.0%
Endpoints live
85.4%
Findings
6 pub · 0 WIP · 0 pre-reg
Endpoint liveness
Full crawl of 2,974 distinct FHIR-REST hosts in the NDH: 93.3% answered HTTP, 85.4% served a parseable CapabilityStatement, 81.6% published valid SMART well-known, 90.3% answered an unauthenticated Practitioner?_count=1 with 200/401. Across the full NDH endpoint population: 5,043,524 endpoints total (74.2% FHIR-REST, 25.8% Direct Project); 98.7% of Organizations carry zero Endpoint references.
NPI and taxonomy correctness
95.72% of 10.9M NDH NPIs clear NPPES (0.79% ghost, 3.49% deactivated). Practitioner name agreement: 94.9% exact → 95.3% normalized → 97.9% Jaro-Winkler ≥0.85. Organization name: 56.3% exact → 88.0% normalized → 98.8% Jaro-Winkler ≥0.85 (closes the 44-point exact-match gap to 1pp). NDH carries NUCC on Practitioner.qualification (99.83% valid) AND Medicare Specialty codes on PractitionerRole.specialty (99.98% valid against the CMS-published crosswalk). Internal cross-system consistency: 85.8% of 3.3M Practitioner↔Role pairs agree via the crosswalk. External NUCC agreement NDH↔NPPES: 93.7% match NPPES's switch='Y' TRUE primary, 99.7% match any of the 15 slots, 6.0% match only a secondary. Slot_1 is NOT always the true primary (14.93% of rows).
Temporal staleness
100.0% of NPD resources carry a meta.lastUpdated value on the release day (2026-04-09). Distinct meta.lastUpdated values range from 1 to 5 across the 6 resource types — meta.lastUpdated on the NPD bulk public-use files is a bulk-export stamp, not a per-resource freshness signal.
Referential integrity
Referential integrity is clean but coverage is sparse. 0.000% of 17.0M declared cross-resource references actually dangle (target missing). But only 3.0% of Endpoints carry a managingOrganization (149,080 of 5,043,524) and only 76.0% of Locations do (2,654,922 of 3,494,239). H8: the NPD bulk export does not ship HealthcareService (NDH IG defines 10 resources; NPD ships 6).
Duplicate detection
Practitioner dedup is clean — 0 excess rows across 7,441,212 NPIs (H14). But Organizations multiply: 70.5% of the 1,999,118 unique Org NPIs map to more than one Organization resource (1,415,777 excess rows; max 5 resources per one NPI). By normalized (name, state, city), 70.3% of keys repeat. Downstream consumers assuming one Organization resource = one real-world entity will be wrong roughly two out of three times.
Network adequacy gauge
Empirical FHIR endpoint liveness vs the 85% Medicare Advantage network-adequacy implied ceiling: L7 unauthenticated-read 90.3% (ABOVE), L5 CapabilityStatement conformance 85.4% (AT), L6 SMART well-known 81.6% (BELOW). Gauge sampled across 2,974 distinct FHIR-REST hosts in the NDH.