Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Joan Threlfall

Individual provider Anesthesiology Physician · NPI 1043210966

Joan Threlfall is registered under Certified Registered Nurse Anesthetist (CRNA) in Washington, District of Columbia. Qualified in 1984, 42 years ago. Practices with Medstar Medical Group II LLC, a 3,717-clinician group and accepts Medicare assignment. Licensed in District of Columbia.

Years since qualifying
42
Licensed in
DC
In the registry since
2005
Specialties on file
2
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Practice location Address checks out

3800 Reservoir Rd NW
Washington, DC 20007-2113 Not confirmed with CMS for 13 years — call before visiting
Phone: (202) 444-8640
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Certified Registered Nurse Anesthetist (primary) Taxonomy 367500000X · Licence RN61761 (DC)
Anesthesiology Physician Taxonomy 207L00000X · Licence 7601061761 (DC)

Record details

NPI number1043210966
Entity typeIndividual (Type 1)
GenderFemale
Sole proprietorNo
NPI enumeratedJuly 22, 2005
Last updated in NPPESApril 11, 2013

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCERTIFIED REGISTERED NURSE ANESTHETIST (CRNA)
Medical schoolOTHER
Graduated 1984 (42 years in practice)
Group practice Medstar Medical Group Ii Llc — 3717 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients98
Services billed 106 a service is one billed item, such as a visit, a test or a procedure
Average patient age68

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $193 2 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Medstar Medical Group II LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 3717 clinicians in the practice; 12 are shown here.

Other providers in Washington