Stefan Sien, D.O.
Pulmonary Disease Physician · Murrieta, CA
Stefan Sien, D.O. is a pulmonary disease physician with a practice address in Murrieta, California, and NPI 1932319464, issued on May 23, 2007. Check the license (California 20A12378, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Stefan Sien
- Credential
- D.O.
- Primary taxonomy
- Pulmonary Disease Physician 207RP1001X
- License number
- 20A12378 CA
Self-reported in NPPES; status is on the state search - Practice location
- 28078 Baxter RD Ste 324, Murrieta, CA 92563
- Phone
- (951) 566-5646
- Enumerated
- May 23, 2007
- Record last updated
- Jun 9, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (951) 566-5670
- Medicare enrollment
- Enrolled (PECOS I20121115000243); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest pulmonary disease physician records → All 1,443 in California → Look up another NPI →
Verify Stefan Sien in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A12378Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2.5 times the Medicare Part D claims of the average pulmonary disease physician in 2024
3,565 Medicare Part D claims for 528 beneficiaries, against an average of 1,425 among the 11,596 providers of this specialty who prescribed in Part D. Brand-name drugs were 65% of claims.
Most prescribed
- Trelegy Ellipta543 claims
- Albuterol Sulfate Hfa430 claims
- Prednisone275 claims
- Breo Ellipta256 claims
- Breztri Aerosphere202 claims
- Anoro Ellipta192 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): 13.3 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).
Industry payments in 2024: $4,942.40
120 payments; by number, the most common kind was food and beverage; the largest payer was Intuitive Surgical, Inc. The 8,806 providers of this specialty with any payment received $5,159.88 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Inspire Pulmonary And Sleep Medicine SpecialistMurrieta, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Stefan Sien among 1,443 pulmonary disease physician records in California
Stefan Sien, D.O. is one of 1,443 pulmonary disease physician records with a practice address in California. 84% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 49% of them.
- NPI issued2007 · 49% of these records are older, 40% newer
- In a Medicare fileYes · 84% of these records are
- In the CMS Doctors and Clinicians fileYes · 74% of these records are
- Graduated2005 · median 2002 among the 1,061 with a school on file
- Record last updated2021 · 55% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RP1001X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Pulmonary Disease Physician providers in California
There are 1,443 pulmonary disease physician records in California.
All 1,443 in California → Every provider in Murrieta → Pulmonary Disease Physician nationwide →
The 8 pulmonary disease physician records with the nearest ZIP codes
- Munif Salek, M.D.Murrieta, CA 925631891890901
- Ramiz Fargo, M.D.Moreno Valley, CA 925551699705509
- Walter Klein, M.D.Moreno Valley, CA 925551366645491
- Aarti Mittal, D.O.Moreno Valley, CA 925551194035691
- Elaine NguyenMoreno Valley, CA 925551386092815
- Suman Thapamagar, M.D.Moreno Valley, CA 925551538484936
- Destry Washburn, D.O.Moreno Valley, CA 925551992021463
- Elizabeth Chuy, M.D.San Jacinto, CA 925831033415773
Common questions
What is Stefan Sien, D.O.'s NPI number?
Stefan Sien, D.O.'s National Provider Identifier (NPI) is 1932319464, issued on May 23, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Stefan Sien, D.O. located?
The NPPES record lists a practice address at 28078 Baxter RD Ste 324, Murrieta, CA, 92563. Phone: (951) 566-5646. Providers update this record themselves, so call before visiting.
How can I verify Stefan Sien, D.O.'s license?
NPPES lists California license number 20A12378, 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 Stefan Sien, D.O. prescribe under Medicare Part D?
In 2024, Stefan Sien, D.O. had 3,565 Medicare Part D claims for 528 beneficiaries; the average among pulmonary disease physician prescribers was 1,425. Part D covers Medicare prescriptions only.
What is Stefan Sien, D.O.'s MIPS final score?
The 2023 MIPS final score is 13.3 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.