Katherine Hartstern, MD
Family Medicine Physician · Oshkosh, WI
Katherine Hartstern, MD is a family medicine physician with a practice address in Oshkosh, Wisconsin, and NPI 1437773652, issued on Jun 3, 2020. Check the license (Wisconsin 82621, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Katherine Hartstern
- Credential
- MD
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License numbers
- 82621 WI
125076039 IL
Self-reported in NPPES; status is on the state search - Practice location
- 1855 S Koeller St, Oshkosh, WI 54902
- Phone
- (920) 738-2000
- Enumerated
- Jun 3, 2020
- Record last updated
- Mar 19, 2025
- Medicaid ID
- 100253512 WI
- Medicare enrollment
- Enrolled (PECOS I20231103002261); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 3,765 in Wisconsin → Look up another NPI →
Also registered at 1855 S Koeller St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Samantha AdamsFamily Nurse Practitioner1467853622
- Kristian Bastress, DNP, APNP, FNP-BCFamily Nurse Practitioner1154947851
- Angela Beach, NP-CFamily Nurse Practitioner1881197028
- Brenda Brusky, NPAdult Health Nurse Practitioner1760749097
- Steven Cavness, PHDPsychologist1669466421
- David Coleman, MDFamily Medicine Physician1639170301
Verify Katherine Hartstern in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 82621Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
39% fewer Medicare Part D claims than the average family medicine physician in 2024
2,152 Medicare Part D claims for 237 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. 48 claims were for opioids.
Most prescribed
- Atorvastatin Calcium127 claims
- Losartan Potassium95 claims
- Levothyroxine Sodium92 claims
- Omeprazole71 claims
- Lisinopril70 claims
- Pantoprazole Sodium70 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 practice group's MIPS final score for 2023 (Medicare payment program): 77.8 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. 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, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $13.36
1 payment: food and beverage; the largest payer was Novo Nordisk Inc. The 55,478 providers of this specialty with any payment received $902.55 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
- Ascension Medical Group-Fox Valley Wisconsin IncOshkosh, WI
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Katherine Hartstern among 3,765 family medicine physician records in Wisconsin
Katherine Hartstern, MD is one of 3,765 family medicine physician records with a practice address in Wisconsin. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2020, is newer than 89% of them.
- NPI issued2020 · 89% of these records are older, 9% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated2020 · median 2007 among the 2,347 with a school on file
- Record last updated2025 · 56% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a Wisconsin practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
52 family medicine physician records list a practice address in Oshkosh
They are 52 of the 1,527 NPPES records with a practice address in Oshkosh, and 3,765 family medicine physician records in Wisconsin.
All 3,765 in Wisconsin → Every provider in Oshkosh → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- David Coleman, MDOshkosh, WI 549021639170301
- David Maruska, MDOshkosh, WI 549021508848847
- Christal Sakrison, MDOshkosh, WI 549021073508487
- James Smrecek, MDOshkosh, WI 549021063407385
- Glenn Vogelsang, M.D., PHDOshkosh, WI 549021538245642
- Thomas Wex, MDOshkosh, WI 549021508851825
- Sarah Wypiszynski, MDOshkosh, WI 549021568994853
- Bobby Yun, MDOshkosh, WI 549021154399061
Common questions
What is Katherine Hartstern, MD's NPI number?
Katherine Hartstern, MD's National Provider Identifier (NPI) is 1437773652, issued on Jun 3, 2020. An NPI identifies a provider in billing; it is not a license.
Where is Katherine Hartstern, MD located?
The NPPES record lists a practice address at 1855 S Koeller St, Oshkosh, WI, 54902. Phone: (920) 738-2000. Providers update this record themselves, so call before visiting.
How can I verify Katherine Hartstern, MD's license?
NPPES lists Wisconsin license number 82621, as entered by the provider. Search the Wisconsin Medical Examining Board at https://dsps.wi.gov/Pages/BoardsCouncils/MEB/Default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Katherine Hartstern, MD prescribe under Medicare Part D?
In 2024, Katherine Hartstern, MD had 2,152 Medicare Part D claims for 237 beneficiaries; the average among family medicine physician prescribers was 3,544. Part D covers Medicare prescriptions only.
What is Katherine Hartstern, MD's MIPS final score?
The 2023 MIPS final score is 77.8 of 100, reported for the practice group. 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.