Quick answers
- Does Karen P. Diaz accept Medicare assignment?
- Yes. Medicare's clinician data says Karen P. Diaz 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 Karen P. Diaz see?
- In 2024, CMS data shows 283 Original Medicare patients and 793 services for Karen P. Diaz. This counts Original Medicare only and measures volume, not quality.
- What is Karen P. Diaz's NPI number?
- 1639602147. 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 Karen P. Diaz, 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 | 283 |
|---|---|
| Services billed to Medicare | 793 |
| Different services or procedures | 64 |
| Participating Medicare provider | Yes |
| Average age of these patients | 72 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)121 services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)81 services
- X-ray of chest, 2 views (71046)50 services
- Automated urinalysis test (81003)48 services
- Albuterol, inhalation solution, fda-approved final product, non-compounded, administered through dme, unit dose, 1 mg (J7613)43 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 cholesterol73%
- High blood pressure65%
- Arthritis46%
- Anxiety25%
- Depression24%
- Diabetes21%
Practice locations
Addresses where Karen P. Diaz is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 13; the Medicare profile lists all.
- 11915 Georgia AveWheaton, MD 20902 (301) 942‑4505
- 12111 Darnestown RdGaithersburg, MD 20878 (301) 926‑3095
- 12220 Rockville PikeRockville, MD 20852 (301) 881‑0103
- 19777 Frederick RdGermantown, MD 20876 (240) 388‑9314
- 20 University Blvd ESilver Spring, MD 20901 (240) 863‑2720
Group practices
Medicare enrollment lists Karen P. Diaz as a member of this group (CMS data updated October 2, 2026).
- MedStar Urgent Care LLC300 clinicians in the group
Specialties
- Physician Assistantprimary
Other physician assistants in Wheaton
Clinicians with the same Medicare primary specialty in Wheaton, MD — not a recommendation.
Other clinicians in MedStar Urgent Care LLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Graduation year | 2016 |
|---|---|
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1639602147 |
| 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