Physician Profile
Unclaimed ProfileAbout WILLIAMSON
Based in Houston, TX, Mark A Williamson, MD is listed in the NPI registry under psychiatry. Mark graduated from University of Texas Medical Branch at Galveston in 1984. Mark is also listed as specialising in child & adolescent psychiatry.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Areas of Expertise
Common questions
What is Dr. Williamson's specialty?
Dr. Williamson is a psychiatry in Houston, TX. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “PSYCHIATRY”.
NPI registry
Where can I find Dr. Williamson?
Dr. Williamson is listed at 5901 LONG DR, Houston, TX 77087. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How do I contact Dr. Williamson?
The number on file is (713) 970-7000. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Williamson's NPI number?
Dr. Williamson's National Provider Identifier is 1760591028. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
What is Dr. Williamson's medical education?
Dr. Williamson attended University of Texas Medical Branch at Galveston, graduating in 1984. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Williamson been practising?
Dr. Williamson has 42 years experience. Calculated from a graduation year of 1984, reported in the CMS National Downloadable File.
CMS public data
What is Dr. Williamson known for?
According to Medicare billing data, Dr. Williamson the Medicare record under this individual NPI shows mainly office visits and diagnostic testing. Hospital-based physicians usually have their procedural work billed by the facility rather than under their own number, so this is a floor on their practice, not a description of it. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Williamson confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Williamson. If this is you, claiming it is free.
Guide.md
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (713) 970-7000
- Email not available
Practice Locations
5901 LONG DR
Houston, TX 77087
Procedures Most Often Billed to Medicare
51 services · 14 patients · 1 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
51 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
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Claim this profileRelated providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other psychiatry specialists at this location 4
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 8
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 24 related providers in 3 groups
Other psychiatry specialists in Houston 8
Same specialty, same city.
Trained at University of Texas Medical Branch at Galveston 8
Other providers in the same specialty who trained at the same institution.
Class of 1984 at University of Texas Medical Branch at Galveston 8
Providers who graduated from the same medical school in the same year.
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.