This page explains exactly where PlainDoctor's data comes from, how we process it, and what limitations apply. Every record on this site is traceable to an official federal data source.

Data Sources

PlainDoctor draws from nine federal (and federally-adjacent) data sources, each maintained and published by U.S. government agencies or the Federation of State Medical Boards:

1. CMS National Plan and Provider Enumeration System (NPPES)

• What it is: The federal registry of all healthcare providers with a National Provider Identifier (NPI), maintained by the Centers for Medicare & Medicaid Services (CMS). Every provider who bills Medicare or Medicaid must be registered.
• What fields we use: NPI number, provider name, credentials (MD, DO, NP, PA, etc.), medical specialty code, practice address, phone number, gender, and enumeration date.
• Update frequency: CMS publishes updated NPPES bulk data files monthly. PlainDoctor refreshes its database from each monthly release.
• Coverage: 7,090,243 active individual healthcare providers (Type 1 NPIs) across all 50 states, D.C., and U.S. territories.
• Official source: download.cms.gov/nppes/NPI_Files.html

2. CMS Five-Star Quality Rating System, Nursing Homes

• What it is: The official CMS quality rating system for Medicare-certified nursing homes, based on health inspections, quality measures, and staffing levels. Ratings range from 1 star (much below average) to 5 stars (much above average).
• What fields we use: Overall rating, health inspection rating, quality measures rating, staffing rating, registered nurse (RN) staffing hours, total deficiencies, complaint-based deficiencies, fines, penalties, bed count, ownership type, and inspection cycle data.
• How ratings are calculated: CMS calculates Five-Star ratings using a combination of on-site health inspections (conducted by trained surveyors), quality measures (clinical outcomes reported by facilities), and staffing data (hours of care per resident per day). The methodology is defined by CMS and is publicly documented.
• Update frequency: CMS updates nursing home ratings monthly based on the most recent survey data.
• Coverage: 14,710 Medicare-certified nursing homes across all 50 states, the District of Columbia, and US territories (Puerto Rico, Guam) - 53 jurisdictions in total.
• Official source: data.cms.gov/provider-data/dataset/4pq5-n9py

3. NUCC Health Care Provider Taxonomy

• What it is: The National Uniform Claim Committee's standardized classification system for healthcare provider types and specialties. It is the industry standard used in Medicare, Medicaid, and commercial insurance billing.
• What fields we use: Taxonomy codes, specialty names, and category groupings. Each NPPES provider record contains a taxonomy code that PlainDoctor resolves to a human-readable specialty name.
• Coverage: 690+ individual provider specialty classifications.
• Official source: nucc.org

4. CMS Medicare Part D Prescriber Data

• What it is: The CMS Medicare Part D Prescriber Public Use File, which contains provider-level data on prescription drug prescribing under Medicare Part D.
• What fields we use: Total claims, total drug cost, beneficiary counts, brand vs. generic breakdown, opioid prescribing rates, and top prescribed drugs per provider.
• Update frequency: CMS publishes this data annually. The current dataset covers calendar year 2023.
• Limitations: Covers Medicare Part D only, does not include commercial insurance, Medicaid, or cash prescriptions. Claims involving fewer than 11 beneficiaries are suppressed by CMS for patient privacy.

5. CMS MIPS Performance Data

• What it is: The Merit-based Incentive Payment System (MIPS) scores published by CMS, measuring provider performance on quality, cost, improvement activities, and promoting interoperability.
• What fields we use: Final MIPS score, quality score, cost score, and promoting interoperability score per provider.
• Update frequency: Published annually by CMS. The current dataset covers the 2023 performance year.

6. CMS Open Payments (Physician Payments Sunshine Act)

• What it is: The federal database of payments and other transfers of value from drug and medical-device manufacturers to physicians, required under the Physician Payments Sunshine Act (part of the Affordable Care Act).
• What fields we use: Total payment amount, payment count, top payer, and payment-nature breakdown per provider, where reported. Shown on individual provider pages.
• Update frequency: CMS publishes Open Payments data annually, by June 30, covering the prior calendar year. The current dataset covers program year 2024.
• Official source: openpaymentsdata.cms.gov

7. State Medical Board Disciplinary Action Annual Reports + FSMB National Rollup

• What it is: Aggregate, statewide disciplinary-action statistics published directly by individual state medical boards in their own public annual reports (e.g. California MBC, New York Health, Florida DOH, Texas TMB, Ohio Medical Board, Illinois IDFPR, Massachusetts BORIM, Michigan LARA, Pennsylvania, Washington), plus a national comparison rollup from the Federation of State Medical Boards' "U.S. Medical Regulatory Trends and Actions" report. These are state-level (or national) counts, never individual-provider disciplinary records.
• What fields we use: Action type, action count, case count, and total licensees per state (or nationally) per year, aggregated into a statewide/national total and rate. Shown on state disciplinary pages and as contextual (non-per-provider) information on individual provider pages.
• Update frequency: Each state board publishes on its own schedule (typically an annual report); FSMB's national report is published roughly every 2 years. There is no single federal release date. PlainDoctor currently covers 10 states (CA, FL, IL, MA, MI, NY, OH, PA, TX, WA) plus the FSMB national rollup, most recently for the 2023 reporting year.
• Limitations: Per-state coverage is limited to the 10 states above; other states are not yet included. Figures are statewide/national aggregates, not individual physician records -- for a specific provider's license or disciplinary status, consult that state's medical board directly (linked on each disciplinary page).

8. CMS Hospital General Information

• What it is: The CMS Care Compare dataset covering facility identity, ownership type, hospital category, emergency-services availability, and the CMS Overall Hospital Quality Star Rating (a composite of mortality, readmission, patient experience, safety, and timely/effective-care measures), published since July 2016.
• What fields we use: Facility name, city, state, overall star rating, hospital type, ownership type, and emergency-services flag. Powers PlainDoctor's hospital profile pages.
• Coverage: 5,432 CMS-tracked hospitals.
• Official source: data.cms.gov/provider-data/dataset/xubh-q36u

9. CMS Doctors and Clinicians National Downloadable File (DAC)

• What it is: CMS's Care Compare dataset linking individual providers (by NPI) to the hospitals/facilities (by CCN) where they report a Medicare billing affiliation.
• What fields we use: Provider-to-facility affiliation links, used to show a provider's hospital affiliations and a hospital's affiliated-clinician count.
• Coverage: 1,760,594 provider-facility affiliation records.
• Limitations: Reflects a reported Medicare billing relationship, not a guarantee that a given provider currently practices at that facility.

Authoritative Verification Sources

PlainDoctor mirrors federal directories. For credential verification or regulatory action checks, consult these authoritative sources directly:

• NPI lookup: CMS NPPES NPI Registry - the official source for active NPI status, last update date, and primary practice address.
• Board certification: ABMS Board Certification - the American Board of Medical Specialties verifies board status across the 24 ABMS Member Boards (Internal Medicine, Surgery, Pediatrics, etc.).
• Federal exclusions: OIG List of Excluded Individuals/Entities - the HHS Office of Inspector General's database of providers excluded from federal health programs (Medicare, Medicaid, etc.).
• Open Payments (industry payments): CMS Open Payments - the federal database of payments and ownership interests from drug and medical device manufacturers to physicians and teaching hospitals.
• Practitioner discipline: National Practitioner Data Bank - the federal repository of medical malpractice payments and adverse actions (access restricted to authorized entities; consumers should contact their state medical board for licensure history).
• State licensure: FSMB State Medical Board Directory - contact information for the state-of-licensure board, which is the official source for current license status and any disciplinary actions.

Data Freshness

Processing Pipeline

Our data processing is designed to present government data accurately without editorial modification:

1. Download: NPPES bulk data files (CSV, ~11 GB) are downloaded from the CMS public data portal with each monthly release. Nursing home data is downloaded from the CMS Provider Data Catalog.
2. Filter: Provider records are filtered to active individual providers (Type 1 NPIs). Organizational providers (Type 2, such as hospitals and clinics) are excluded.
3. Classify: NUCC taxonomy codes are resolved to human-readable specialty names and categories using the official NUCC code set.
4. Normalize: Practice addresses, phone numbers, and credential designations are standardized for consistent display. No data values are altered, only formatting.
5. Index: Providers are indexed by specialty, state, city, and name to enable search and browsing.
6. Aggregate: State-level and specialty-level statistics are computed from the underlying provider records for summary pages.
7. Validate: Record counts are verified against CMS published totals. Any provider with an NPI shown on PlainDoctor can be independently verified at the CMS NPI registry.

What Data We Show

• Provider name and credentials (MD, DO, NP, PA, etc.) as reported in NPPES
• Medical specialty from NUCC taxonomy codes
• Practice address and phone number
• NPI number
• Gender as reported in NPPES
• Enumeration date (when the NPI was assigned)
• Nursing home ratings (official CMS Five-Star scores)
• Medicare Part D prescribing statistics
• MIPS quality performance scores
• Industry payments (CMS Open Payments / Sunshine Act totals, where reported for a provider)
• Statewide disciplinary-action context (aggregate counts from each state medical board's own annual report, for the 10 states currently covered -- never an individual provider's disciplinary record)
• Hospital profiles (CMS Hospital General Information: facility identity, ownership, overall star rating, emergency-services flag)
• Provider-hospital affiliations (CMS Doctors and Clinicians National Downloadable File: which facilities a provider reports a Medicare billing relationship with)

What We Do NOT Show

• Custom quality ratings or proprietary performance scores
• Patient reviews or user-submitted content
• Individual physician malpractice history or personal disciplinary records (only aggregate, statewide disciplinary counts for 10 states -- see above)
• Insurance acceptance information

Coverage

• Providers: 7,090,243 active individual healthcare providers
• Specialties: 690+ medical specialties (NUCC taxonomy)
• Nursing Homes: 14,710 Medicare-certified facilities
• Geographies: All 50 states, D.C., and U.S. territories (56 jurisdictions)
• Open Payments: 979,136 provider-year payment records (program year 2024)
• State Disciplinary Actions: 10 states (CA, FL, IL, MA, MI, NY, OH, PA, TX, WA) plus the FSMB national rollup
• Hospitals: 5,432 CMS-tracked facilities
• Provider-hospital affiliations: 1,760,594 records

Limitations

• Provider information is self-reported to CMS and may not be fully current. Providers are responsible for updating their own NPPES records.
• Not all healthcare providers have NPIs, only those that bill Medicare or Medicaid are required to register.
• Practice address may be an administrative or billing address rather than where the provider sees patients.
• Medicare Part D prescribing data reflects Medicare only and does not include commercial insurance, Medicaid, or cash prescriptions.
• Nursing home ratings reflect a point-in-time assessment and may not capture recent changes in facility quality.
• PlainDoctor is not affiliated with CMS, the Department of Health and Human Services, or any government agency.

Verify Our Data

Every record on PlainDoctor can be independently verified using official government tools:

• Provider NPI: CMS NPI Registry Lookup
• Nursing Home Ratings: Medicare Care Compare
• Raw Data Downloads: CMS Data Portal