Hospital Community Health Needs Assessment (CHNA) Findings: an open dataset (Hidden Health Data)

Hidden Health Data: U.S. non-profit hospital Community Health Needs Assessments (CHNAs, IRC 501(r)(3)), extracted via Claude claude-haiku-4-5 with a verification layer (grounding, neurosymbolic constraints, ensemble, conformal gate). This release (v0.4.8) — expanded national crawl: 779,502 records from 2,622 source documents (7,238 hospitals): 618,048 identified community health needs, 161,454 implementation strategies. Every record carries full provenance and a quality/trust score; nothing is imputed or dropped. AI-extracted, not yet independently validated — preliminary; filter on the trust score. Public-record documents only; no PHI. Code (Apache-2.0): github.com/sanjaybasu/dark-health-data. CC0-1.0.