Individual provider

Yingxi Chen, MD, PHD

Research Study Specialist Health Information Specialist/Technologist Public Health or Welfare Agency

Yingxi Chen, MD, PHD is a provider specialising in Public Health or Welfare Agency in Dover, DE, registered under NPI 1649121138. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.

Getting there

The practice address on file is 8 THE GRN # 23699, Dover, DE 19901. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

8 THE GRN # 23699, Dover, DE 19901 Open in Google Maps →

Credentials and Medicare

State licence

NPPES does not list a state licence number for this record. That is not unusual — organizations and some provider types are not required to file one. Verify current licensure with the relevant state board before care.

Medicare (PECOS)

This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.

What Public Health or Welfare covers

Definition to come... NUCC Health Care Provider Taxonomy, code 251K00000X
Agencies Public Health or Welfare

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
1744R1102X Research Study Specialist Research Study
246Y00000X Health Information Specialist/Technologist
251K00000X Public Health or Welfare Agency primary

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1649121138 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateFeb 9, 2026
Last updatedFeb 16, 2026
StatusActive
Sole proprietorYes
GenderFemale
CredentialMD, PHD
Practice address 8 THE GRN # 23699
Dover, DE 19901
(757) 689-7437
This record was updated on Feb 16, 2026, which is recent enough that the contact details are likely still accurate.

Number check

1649121138 passes the NPI check digit test The final digit 8 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 6 4 9 1 2 1 1 3
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 6 8 9 2 2 2 1 6

Sum = 62 · next multiple of 10 = 70 · check digit = 8 · actual last digit = 8

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1649121138?
NPI 1649121138 is the National Provider Identifier assigned to Yingxi Chen, MD, PHD in Dover, DE. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Public Health or Welfare Agency cover?
Definition to come...
How do I contact Yingxi Chen, MD, PHD?
The phone number on file with NPPES is (757) 689-7437, last updated Feb 16, 2026. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Is NPI 1649121138 a valid number?
Yes. 1649121138 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.