Africa South of the SaharaAnemia, Iron-DeficiencyGastrointestinal Neoplasms
Dr. Dirk Jacob Van Leeuwen, MD, PhD
NPI1205941309
- Medicare services, 2023
- 45
- Medicare patients, 2024
- 29
- Part D claims, 2024
- 40
- Publications
- 11
- Hospital affiliations
- 1
- Practice address
- 855 N Westhaven Drive, Oshkosh, WI 54904
- Practice phone
- Call (920) 456-6000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Van Leeuwen's professional email, personal email and mobile number
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Dr. Dirk Jacob Van Leeuwen is a gastroenterologist in Oshkosh, Wisconsin
Dr. Van Leeuwen practices at Aurora Medical Center - Oshkosh in Oshkosh, Wisconsin, part of Advocate Health.
Dr. Van Leeuwen's NPI, 1205941309, was assigned on August 20, 2006. Dr. Van Leeuwen holds Oregon license CP206793.
NPI and contact details
- NPI
- 1205941309NPI Registry (opens in a new tab)
- NPI enumeration date
- August 20, 2006
- NPI status
- Active
- Practice phone
- (920) 456-6000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 73
- Medical school graduation
- 1979
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Dirk Jacob Van Leeuwen practices at Aurora Medical Center - Oshkosh in Oshkosh, Wisconsin
Dr. Van Leeuwen's primary practice is Aurora Medical Center - Oshkosh, at 855 N Westhaven Drive, Oshkosh, WI 54904 in Winnebago County. The practice phone is (920) 456-6000.
- Aurora Medical Center - Oshkosh855 N Westhaven Drive, Oshkosh, WI 54904 · Winnebago CountyPhone(920) 456-6000
Sources: Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Dirk Jacob Van Leeuwen is affiliated with 3 sites of care and 3 medical groups
Dr. Van Leeuwen's primary practice is Aurora Medical Center - Oshkosh in Oshkosh, Wisconsin, part of Advocate Health. The medical group on file is Aurora Medical Group. Dmand AI also links Dr. Van Leeuwen to 2 more group practices and clinics and 2 medical groups, each named with a free account.
Aurora Medical Group2 group practices and clinicsNames with a free account2 medical groupsNames with a free account
See all 6 affiliations for Dr. Van LeeuwenSources: Dmand AI Affiliation Data; Doctors and Clinicians National Downloadable File (CMS); and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Dirk Jacob Van Leeuwen's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Van Leeuwen practices, 3 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Aurora Medical Center - Oshkosh | Available with a free account |
| +2 more sites and 2 medical groups | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Dirk Jacob Van Leeuwen is one of 277 gastroenterologists in Wisconsin
Gastroenterology is Dr. Van Leeuwen's primary specialty in the NPI Registry, under taxonomy code 207RG0100X. Dmand AI has Dr. Van Leeuwen's licenses on file in 2 states: Oregon and Kentucky.
Specialties and state licenses
- Gastroenterology, OregonPrimary
- Kentucky license
Gastroenterologists near Dr. Van Leeuwen
Counts of gastroenterologists with a Dmand AI profile, by place and practice. Each opens the list.
277gastroenterologists in Wisconsin
7gastroenterologists in Oshkosh
5gastroenterologists at Aurora Medical Center - OshkoshSources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Dirk Jacob Van Leeuwen billed Medicare for 45 services in 2023
CMS data shows 45 Medicare services from Dr. Van Leeuwen across 4 procedure codes in 2023, for 29 Medicare patients. Medicare paid $3,493 for them.
Medicare services, 202345
Medicare patients29
Paid by Medicare$3,493
Procedure codes4
Dr. Van Leeuwen's Medicare services by type, 2021 to 2023
- 2021
- 2023
- Office and hospital visits
- 2021: 542023: 2357%
- Surgery
- 2021: 02023: 22
Where Dr. Van Leeuwen's Medicare services took place, 2023
- In an office1124%
- In a facility3476%
Dr. Van Leeuwen compared with the Wisconsin median for gastroenterologists, 2023
- Dr. Van Leeuwen
- Wisconsin median
- Medicare services
- 45vs 32986% below
- Medicare patients
- 29vs 25889% below
- Part D claims
- 15vs 42997% below
Medians across 278 gastroenterologists in Wisconsin with Dmand AI profiles that report each measure.
Dr. Van Leeuwen's most billed Medicare procedure codes, 2023
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
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Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Van Leeuwen and other gastroenterologists in Wisconsin.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Dirk Jacob Van Leeuwen treated 29 Medicare patients in 2024, average age 74
CMS counts 29 Medicare patients who saw Dr. Van Leeuwen in 2024. The largest group is 75 to 84, with 13 patients. 75% of them have high blood pressure, and 75% have high cholesterol. Their average risk score is 2.18, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.
Across all payers, Dmand AI patient panel data puts Dr. Van Leeuwen's median patient age at 68, with 50% women.
Medicare patients, 202429
Average age74
Average risk score2.18
Dr. Van Leeuwen's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Van Leeuwen's Medicare patients by sex, 2024
- Women1448%
- Men1552%
Chronic conditions among Dr. Van Leeuwen's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Arthritis59%
- Ischemic heart disease55%
- Chronic kidney disease48%
- Diabetes41%
Share of Medicare patients with each condition. A patient can have several.
Dr. Van Leeuwen's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 68
Patient panel by sex, all payers
- Women50%
- Men50%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Dirk Jacob Van Leeuwen wrote 40 Medicare Part D claims in 2024
In 2024, Dr. Van Leeuwen wrote 40 Medicare Part D claims for 14 patients. 88% of them were for generic drugs. CMS names the drug for 15 of them, across 1 drug with 11 or more claims each, at $70 in total drug cost. In 2023, CMS named 16 claims across 1 drug.
Part D claims, 202440
Drugs named by CMS1
Total drug cost$70
Part D patients14
Dr. Van Leeuwen's Part D claims by kind of drug, 2024
- Generic35 claims88%
- Brand-name and other5 claims13%
Dr. Van Leeuwen's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 162024: 156%
Drugs named by CMS: 1 in 2024, 1 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
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Dr. Dirk Jacob Van Leeuwen has 11 publications on record
Dmand AI links 11 papers to Dr. Van Leeuwen, published from 2013 to 2021. 2018 was the busiest year, with 2. The most frequent topics are Hypertension, Portal and Liver. Dr. Van Leeuwen's most frequent co-authors are James M. Crawford, MD, PhD, Ryan Michael Gill, MD, PhD and Saeed Hamid, MD.
Papers11
Years published2013 to 2021
Dr. Van Leeuwen's papers by year, 2013 to 2021
Topics Dr. Van Leeuwen writes about most
- Hypertension, Portal
- Liver
Dr. Van Leeuwen's most frequent co-authors
- James M. Crawford, MD, PhD5 shared papers
- Ryan Michael Gill, MD, PhD2 shared papers
- Saeed Hamid, MD1 shared paper
Recent publications by Dr. Van Leeuwen
Hypertension, PortalLiver
Expert Rev Gastroenterol Hepatol
Acute-On-Chronic Liver FailureBiopsyDiagnosis, Differential
See who Dr. Van Leeuwen researches with
Physician Network Discovery turns co-authorship, shared hospitals and shared groups into a map of who Dr. Van Leeuwen works with, so you can find a warm path to the right gastroenterologists.
Sources: PubMed (National Library of Medicine); and Dmand AI Research Linkage
Sources for Dr. Dirk Jacob Van Leeuwen's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation DataDoctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDoctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Dmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| Publications, topics and co-authors | PubMed (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Dirk Jacob Van Leeuwen
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Dirk Jacob Van Leeuwen's NPI number?
Dr. Dirk Jacob Van Leeuwen's NPI number is 1205941309. It was assigned on August 20, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Dirk Jacob Van Leeuwen?
Dr. Dirk Jacob Van Leeuwen is a gastroenterologist in Oshkosh, Wisconsin. The primary specialty in the NPI Registry is Gastroenterology Physician (taxonomy code 207RG0100X).
Where does Dr. Dirk Jacob Van Leeuwen practice?
Dr. Van Leeuwen practices at 855 N Westhaven Drive, Oshkosh, WI 54904. Dr. Van Leeuwen's primary practice is Aurora Medical Center - Oshkosh in Oshkosh, Wisconsin, part of Advocate Health. Dmand AI also links Dr. Van Leeuwen to 2 group practices and clinics and 2 medical groups.
What is Dr. Dirk Jacob Van Leeuwen's office phone number?
The practice phone on file for Dr. Van Leeuwen is (920) 456-6000.
What is Dr. Dirk Jacob Van Leeuwen's medical license number?
Dr. Van Leeuwen holds Oregon license CP206793, one of the licenses on file in 2 states.
Which states has Dr. Dirk Jacob Van Leeuwen been licensed in?
Dmand AI has state licenses on file for Dr. Van Leeuwen in Oregon and Kentucky.
Which hospitals is Dr. Dirk Jacob Van Leeuwen affiliated with?
Dr. Van Leeuwen practices at Aurora Medical Center - Oshkosh in Oshkosh, Wisconsin.
What medical group is Dr. Dirk Jacob Van Leeuwen part of?
Dr. Van Leeuwen is linked to Aurora Medical Group. Dmand AI links Dr. Van Leeuwen to 2 more medical groups.
Does Dr. Dirk Jacob Van Leeuwen accept Medicare?
Yes. CMS data shows Dr. Van Leeuwen billed Medicare for 45 services in 2023.
How many Medicare patients does Dr. Dirk Jacob Van Leeuwen see?
CMS counts 29 Medicare patients who saw Dr. Van Leeuwen in 2024, with an average age of 74.
Show 5 more questionsShow fewer questions
What services does Dr. Dirk Jacob Van Leeuwen bill to Medicare?
In 2023, Dr. Van Leeuwen's most billed Medicare services were hospital inpatient care (99221), surgery: digestive system (43235) and surgery: digestive system (43239).
What drugs does Dr. Dirk Jacob Van Leeuwen prescribe most?
In 2024 Medicare Part D data, Dr. Van Leeuwen's most prescribed drugs by claims were Pantoprazole Sodium.
How long has Dr. Dirk Jacob Van Leeuwen been practicing?
Dr. Van Leeuwen graduated from medical school in 1979, 47 years ago.
Does Dr. Dirk Jacob Van Leeuwen do research?
Dmand AI links 11 publications to Dr. Van Leeuwen, published from 2013 to 2021.
Who does Dr. Dirk Jacob Van Leeuwen publish with?
Dr. Van Leeuwen's most frequent co-authors are James M. Crawford, MD, PhD (5 shared papers), Ryan Michael Gill, MD, PhD (2 shared papers) and Saeed Hamid, MD (1 shared paper).
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