John Holder, M.D.
John Holder, M.D. is a Diagnostic Radiology Physician in Little Rock, AR, registered under NPI 1891897120. 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 224 KINGS ROW DR, Little Rock, AR 72207. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| R-2118 | AR | Diagnostic Radiology Physician primary |
This provider holds licence R-2118 issued in AR. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
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 Diagnostic Radiology covers
A radiologist who utilizes x-ray, radionuclides, ultrasound and electromagnetic radiation to diagnose and treat disease. NUCC Health Care Provider Taxonomy, code 2085R0202X
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.
| NPI | 1891897120 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Sep 5, 2006 |
| Last updated | Jun 26, 2008 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
224 KINGS ROW DR Little Rock, AR 72207 (501) 664-4159 |
| Other identifiers |
300030897
· Other (AR) 104173001 · Medicaid (AR) |
Number check
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 | 8 | 9 | 1 | 8 | 9 | 7 | 1 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 9 | 1 | 7 | 9 | 5 | 1 | 4 |
Sum = 70 · next multiple of 10 = 70 · check digit = 0 · actual last digit = 0
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.