Quick answers
- Does Shannen K. Allen accept Medicare assignment?
- Yes. Medicare's clinician data says Shannen K. Allen 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 Shannen K. Allen see?
- In 2024, CMS data shows 815 Original Medicare patients and 1,835 services for Shannen K. Allen. This counts Original Medicare only and measures volume, not quality.
- What is Shannen K. Allen's NPI number?
- 1407876360. 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 Shannen K. Allen, 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 | 815 |
|---|---|
| Services billed to Medicare | 1,835 |
| Different services or procedures | 13 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Established patient complete exam of visual system (92014)951 services
- Photography of the retina (92250)202 services
- Imaging of optic nerve (92133)196 services
- Exam of visual field with extended testing (92083)176 services
- Exam of the internal drainage system of eye (92020)175 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 cholesterol75%
- High blood pressure64%
- Arthritis40%
- Diabetes28%
- Ischemic heart disease22%
- Osteoporosis21%
Practice locations
Addresses where Shannen K. Allen is enrolled with Medicare (CMS data updated October 2, 2026).
- 14955 Shady Grove Rd, Suite 180Rockville, MD 20850 (301) 279‑9696
Group practices
Medicare enrollment lists Shannen K. Allen as a member of this group (CMS data updated October 2, 2026).
- Robert C. Feldman, MD, PA6 clinicians in the group
Specialties
- Ophthalmologyprimary
Other ophthalmologists in Rockville
Clinicians with the same Medicare primary specialty in Rockville, MD — not a recommendation.
Other clinicians in Robert C. Feldman, MD, PA
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Johns Hopkins University School Of Medicine |
| Graduation year | 2002 (24 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1407876360 |
| 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