Quick answers
- Does John G. Hagen accept Medicare assignment?
- Yes. Medicare's clinician data says John G. Hagen accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does John G. Hagen see?
- In 2024, CMS data shows 270 Original Medicare patients and 287 services for John G. Hagen. This counts Original Medicare only and measures volume, not quality.
- What is John G. Hagen's NPI number?
- 1649430026. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for John G. Hagen, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 270 |
|---|---|
| Services billed to Medicare | 287 |
| Different services or procedures | 50 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Anesthesia for other procedure on esophagus, stomach, or upper small bowel using an endoscope (00731)49 services
- Anesthesia for x-ray or radiation therapy (01922)39 services
- Anesthesia for procedure on anus and rectum (00902)14 services
- Anesthesia for other closed procedure on chest (00520)13 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)57%
- Arthritis52%
- Ischemic heart disease35%
- Diabetes34%
Practice locations
Addresses where John G. Hagen is enrolled with Medicare (CMS data updated October 2, 2026).
- 1275 York AveNew York, NY 10065 (212) 639‑2000
- 650 Commack RdCommack, NY 11725 (631) 623‑4034
Group practices
Medicare enrollment lists John G. Hagen as a member of these groups (CMS data updated October 2, 2026).
- Memorial Anesthesiology Group302 clinicians in the group
- MSKCC Regional Network136 clinicians in the group
Specialties
- Anesthesiologyprimary
Other anesthesiologists in New York
Clinicians with the same Medicare primary specialty in New York, NY — not a recommendation.
Other clinicians in Memorial Anesthesiology Group
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | State University Of New York Downstate Medical Center |
| Graduation year | 2007 (19 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1649430026 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians