Built on the authoritative federal record
The primary sources, named on every page.
These are the federal agencies whose public datasets Fonteum ingests and attributes — the issuing authorities, not customers or partners. Every figure on the site links back to one of them.
See the full source registry, with license and refresh cadence for each →
Reproducible by design
Every figure traces to its federal source.
14-tuple provenance
Every rendered fact ties to a source URL, dataset ID, snapshot date, row key, and SHA-256 — the full chain-of-custody record.
Reproducible SQL
Each study ships the exact query behind its figures, run against the cited federal snapshot. Re-run it yourself.
Daily reconciliation
Published counts are reconciled against the upstream federal datasets on a daily cadence, with drift logged.
Named medical review
Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.
Two doors
Use the free API and open data
Query providers, facilities, sanctions, and quality scores — each field carrying its federal source. Self-serve, no call to start.
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Managed pilots, enterprise terms, and audit-ready, signed attestation packages for compliance, risk, and research teams.
The substrate, by the numbers
6.71 active ophthalmologists per 100,000 residents — ranked 26 of 51 U.S. states + DC.
Three states whose ophthalmologist per-100k density is closest to South Dakota's — useful for benchmarking.
Plain-text citation block — paste verbatim into a brief, story, or report.
South Dakota has 62 active ophthalmologists (6.71 per 100,000 residents) — ranked 26 of 51 U.S. states + DC. Source: CMS NPPES NPI Registry + U.S. Census Bureau, snapshot 2026-05-06. Threshold for "underserved" in the parent study: 5 per 100,000. Citation: Fonteum Research, /research/ophthalmologist-supply-by-state-2026.