Healthcare Provider Guides
Plain-language guides to help you find and verify healthcare providers, understand medical specialties, and navigate insurance and telehealth options, written for patients and researchers, sourced from federal CMS and NIH data. According to the federal National Provider Identifier Registry (CMS NPPES), PlainDoctor compiles more than 7 million U.S. healthcare-provider records, a registry maintained since May 2007, adding Medicare Part D prescribing from 2023 and CMS MIPS quality scores from 2024 where reported, which you can search and compare; our methodology documents every federal source.
How to Find a Doctor: A Step-by-Step Guide
Use the NPI registry to verify providers, understand credentials like MD, DO, NP, and PA, and ask the right questions before choosing a new doctor.
Medical Specialties Explained: Who Treats What
Understand the difference between primary care and specialists, major specialty categories, sub-specialties, and how NPI taxonomy codes work.
In-Network vs Out-of-Network: Understanding Provider Networks
Learn how insurance networks affect your costs, what balance billing means, your rights under the No Surprises Act, and how to verify network status.
Telehealth Guide: Virtual Care Options in 2026
What conditions are appropriate for telehealth, types of virtual care, how insurance covers it, and how to find telehealth-enabled providers.
How to Verify a Doctor's Credentials and Licenses
Look up NPI numbers, check state medical board licenses, verify board certification through ABMS and AOA, and search disciplinary action databases.
What Medicare Claims Data Tells You About a Provider
How CMS utilization data reveals a provider's practice patterns, procedure volume, prescribing habits, and billing behavior, and how to use it before your next appointment.
Understanding Medicare Part D Prescribing Data
What CMS prescribing data reveals about doctor prescribing patterns, brand-vs-generic ratios, opioid flags, and what the numbers mean for provider quality.
What do these guides cover?
PlainDoctor guides are written to help patients and caregivers understand how the U.S. healthcare provider system works. All information draws on official government data, including the CMS National Plan and Provider Enumeration System (NPPES), the American Board of Medical Specialties (ABMS), and state medical boards. Use our specialty directory and state pages to search providers in your area.
Methodology
Every fact on PlainDoctor traces to a federal data source. Provider records come from the CMS National Plan and Provider Enumeration System (updated monthly), with specialty classifications drawn from the National Uniform Claim Committee Health Care Provider Taxonomy, prescribing statistics from the Medicare Part D Prescriber Public Use File for the 2023 reporting year, quality performance from the Merit-based Incentive Payment System for that same period, and nursing home ratings from the Five-Star Quality Rating System indexed by CMS Certification Number and refreshed monthly through Care Compare. Guides cite these primary federal sources directly rather than paraphrasing secondary summaries.
We do not add proprietary scores, editorial ratings, or user-submitted content; figures are presented exactly as CMS publishes them, with limitations (data self-reporting lag, Part D-only prescribing coverage, CMS suppression of beneficiary cells under 11) called out on every page. See the full data methodology for sourcing, pipeline, coverage, and known limitations.