Brianna Thiessen
Emergency Medicine Physician · Riverside, CA
Brianna Thiessen is an emergency medicine physician with a practice address in Riverside, California, and NPI 1588018584, issued on Apr 16, 2016. Check the license (California 20A20763, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Brianna Thiessen
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License number
- 20A20763 CA
Self-reported in NPPES; status is on the state search - Practice location
- 10800 Magnolia Ave, Riverside, CA 92505
- Phone
- (833) 574-2273
- Enumerated
- Apr 16, 2016
- Record last updated
- Oct 27, 2023
- Medicare enrollment
- Enrolled (PECOS I20230914001106); accepts Medicare assignment
- Entity
- Type 1 · individual
Also registered at 10800 Magnolia Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Joseph Abapo, MDPediatrics Physician1841348786
- Hussein Abdulrassoul, MDOrthopaedic Surgery Physician1972123891
- Kimberly Adams, PA-CMedical Physician Assistant1053522870
- Alfredo Aguiar, PAPhysician Assistant1043368970
- Michael Aguinaldo, M.D.Pediatrics Physician1851531487
- Maria Aguirre, MDPediatrics Physician1295806255
Verify Brianna Thiessen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A20763Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
About as many Medicare Part D claims as the average emergency medicine physician in 2024
227 Medicare Part D claims for 147 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D. Brand-name drugs were 9% of claims. 28 claims were for opioids.
Most prescribed
- Cefpodoxime Proxetil32 claims
- Oxycodone Hcl25 claims
- Ondansetron Odt14 claims
- Prednisone14 claims
- Doxycycline Monohydrate13 claims
- Amoxicillin-Clavulanate Potass12 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The MIPS final score for 2023 (Medicare payment program): 32.9 of 100
The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Southern California Permanente Medical GroupRiverside, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Emergency Medicine Physician providers in California
There are 7,751 emergency medicine physician records in California.
Other emergency medicine physician records in California
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- Pyra Aarden, MDMartinez, CA1417058199
- Neal Aaron, D.O.Encinitas, CA1114283520
- Eric AaserudeWalnut Creek, CA1811491194
- Nader Abas, MDBarstow, CA1346288305
- Michael Abbo, MDNovato, CA1205819042
- Daniel Abbott, MDFullerton, CA1518907864
- Paul-Andre Abboud, M.D.Oakland, CA1710065503
- Mostafa Abdel-Hamid, MDStanford, CA1457918740
- Ashraf Abdel-KerimChino, CA1396961538
Common questions
What is Brianna Thiessen's NPI number?
Brianna Thiessen's National Provider Identifier (NPI) is 1588018584, issued on Apr 16, 2016. An NPI identifies a provider in billing; it is not a license.
Where is Brianna Thiessen located?
The NPPES record lists a practice address at 10800 Magnolia Ave, Riverside, CA, 92505. Phone: (833) 574-2273. Providers update this record themselves, so call before visiting.
How can I verify Brianna Thiessen's license?
NPPES lists California license number 20A20763, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Brianna Thiessen prescribe under Medicare Part D?
In 2024, Brianna Thiessen had 227 Medicare Part D claims for 147 beneficiaries; the average among emergency medicine physician prescribers was 226. Part D covers Medicare prescriptions only.
What is Brianna Thiessen's MIPS final score?
The 2023 MIPS final score is 32.9 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.