John James Walker , MPAS, DSC, APA-C
Physician Assistant • Winchester, VA
1870 Amherst St Ste C
Winchester, VA 226012841
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
-
NPI assigned on September 25, 2006; this date does not establish years in practice.
-
Published CMS data list 159 Original Medicare Part B services in 2024.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Published rows only; this is not a quality measure.
-
Published Part B service records, 2024:
- 99213 — Established patient outpatient office visit: 75 service units.
- 99222 — Initial hospital care with straightforward or low-level medical decision making: 41 service units.
- 99221 — Initial hospital care with straightforward or low level of medical decision making, per day: 28 service units.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Units differ by code; these are not visits or a measure of quality.
CPT® only copyright 2023 American Medical Association. All rights reserved. Service names are shortened from CPT Consumer Friendly Descriptors (CMS data, 2024). CPT notice
See all 4 records in the table · Guide: How to read Medicare Part B data
-
Published CMS data list 14 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Published rows only; this is not a quality measure.
-
Published Part D records, 2024:
- Hydrocodone-Acetaminophen (Hydrocodone/Acetaminophen) — 14 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See the full table · Guide: How to read Medicare Part D prescriber data
-
Fewer Medicare Part B services than 65% of clinicians listed under Physician Assistant in Winchester, VA (2024, 84 clinicians with data). Median for this group: 365. Middle half: 116 to 848.
Fewer Medicare Part B services than 65% of clinicians listed under Physician Assistant in Virginia (2024, 2,247 clinicians with data). Median for this group: 288. Middle half: 107 to 693.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Billing and prescribing volume is not a quality rating.
-
Medicare Part B services went from 203 in 2020 to 159 in 2024.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2020–2024.
Practice Location & Contact Primary Location
1870 Amherst St Ste C
Winchester, VA 226012841
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
What Public CMS Data Show
Physician Assistant: NPPES taxonomy is a reported classification, not proof of board certification.
Medicare patients
170 people with Original Medicare in 2024
It gives a sense of how many people with Medicare this clinician treated that year.
Source: CMS, Medicare Physician & Other Practitioners – by Provider, 2024.
Medicare-allowed amount
About $13,817 in 2024
The total amount Medicare approved for these services in 2024. It includes what Medicare paid and what patients or their other insurance owed, such as the deductible and coinsurance.
It shows the total cost of this clinician's Original Medicare services under Medicare's fee rules.
What this does not show: Medicare-allowed amount
This is not the clinician's income. Part of it can go to a clinic or group practice, staff, equipment or drugs. It is not the price you will pay.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024.
Paid by Medicare
About $10,072 in 2024
The part of the Medicare-allowed amount that Medicare itself paid in 2024, after patients' deductibles and coinsurance.
The gap between the allowed amount and this number is roughly what patients and their other insurance paid.
What this does not show: Paid by Medicare
This is not the clinician's income and not a measure of quality.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024.
30-day fills
14 standardized 30-day fills in 2024
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$113 in 2024
The total cost of these prescriptions in 2024, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024.
Open Payments general payments, program year 2025
All general payments: $108.35 across 3 records.
By nature of payment
- Food and Beverage: $108.35 across 3 records.
Reporting-company totals
- Boston Scientific Corporation: $88.82 across 2 records.
- Astellas Pharma US Inc: $19.53 across 1 record.
A reported payment does not necessarily mean the financial relationship is improper and is not a measure of care quality. Clinicians can review and dispute these records.
Source: Calculated by T-MedInfo from CMS Open Payments general-payment records for program year 2025 (published June 30, 2026).
NPI first issued
2006
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Medicare assignment not listed
CMS data do not show whether this clinician accepts Medicare assignment. This does not mean they do not accept Medicare. Ask the office.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, “Does your provider accept Medicare as full payment?”
No telehealth indicator
CMS shows this indicator only when recent Medicare claims include telehealth services. The clinician may still offer telehealth; ask the office.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Enrolled in Medicare (PECOS)
John Walker has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists John Walker as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Winchester and Virginia
Billing and prescribing volume is not a quality rating.
Medicare Part B services
Fewer Medicare Part B services than 65% of clinicians listed under Physician Assistant in Winchester, VA (2024, 84 clinicians with data). Median for this group: 365. Middle half: 116 to 848.
Fewer Medicare Part B services than 65% of clinicians listed under Physician Assistant in Virginia (2024, 2,247 clinicians with data). Median for this group: 288. Middle half: 107 to 693.
Medicare-allowed amount
A lower Medicare-allowed amount than 65% of clinicians listed under Physician Assistant in Winchester, VA (2024, 84 clinicians with data). Median for this group: $29,009. Middle half: $12,231 to $56,353.
A lower Medicare-allowed amount than 65% of clinicians listed under Physician Assistant in Virginia (2024, 2,247 clinicians with data). Median for this group: $23,153. Middle half: $9,003 to $44,800.
Paid by Medicare
A lower Medicare payment amount than 70% of clinicians listed under Physician Assistant in Winchester, VA (2024, 84 clinicians with data). Median for this group: $21,928. Middle half: $9,190 to $38,454.
A lower Medicare payment amount than 65% of clinicians listed under Physician Assistant in Virginia (2024, 2,247 clinicians with data). Median for this group: $17,218. Middle half: $6,803 to $32,639.
Medicare Part D prescriptions
Fewer Part D prescriptions than 95% of clinicians listed under Physician Assistant in Winchester, VA (2024, 88 clinicians with data). Median for this group: 328. Middle half: 92 to 756.
Fewer Part D prescriptions than 95% of clinicians listed under Physician Assistant in Virginia (2024, 2,256 clinicians with data). Median for this group: 247. Middle half: 75 to 708.
Part D drug cost
A lower Part D drug cost than 95% of clinicians listed under Physician Assistant in Winchester, VA (2024, 88 clinicians with data). Median for this group: $4,201. Middle half: $790 to $70,596.
A lower Part D drug cost than 90% of clinicians listed under Physician Assistant in Virginia (2024, 2,256 clinicians with data). Median for this group: $3,441. Middle half: $640 to $57,211.
217 active clinicians are listed under Physician Assistant with a practice address in Winchester, VA (4,411 in Virginia).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Winchester
10.6% of these 217 clinicians have the CMS telehealth indicator.
53% of these 217 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
-
Medicare Part B services
Medicare Part B services decreased 22% from 203 in 2020 to 159 in 2024.
- 2020: 203
- 2021: 149
- 2022: 103
- 2023: 173
- 2024: 159
-
Medicare-allowed amount
Medicare-allowed amount decreased 11% from $15,453 in 2020 to $13,817 in 2024.
- 2020: $15,453
- 2021: $13,164
- 2022: $9,564
- 2023: $15,779
- 2024: $13,817
-
Paid by Medicare
Paid by Medicare decreased 13% from $11,531 in 2020 to $10,072 in 2024.
- 2020: $11,531
- 2021: $8,882
- 2022: $6,513
- 2023: $12,123
- 2024: $10,072
-
Medicare Part D prescriptions
Medicare Part D prescriptions went from 14 in 2020 to 14 in 2024.
- 2020: 14
- 2021: 20
- 2022: 17
- 2023: 21
- 2024: 14
-
30-day fills
30-day fills went from 14 in 2020 to 14 in 2024.
- 2020: 14
- 2021: 20
- 2022: 17
- 2023: 21
- 2024: 14
-
Part D drug cost
Part D drug cost went from $133 in 2020 to $113 in 2024.
- 2020: $133
- 2021: $139
- 2022: $171
- 2023: $185
- 2024: $113
-
Industry payments (Open Payments)
Industry payments (Open Payments) went from $14.68 in 2022 to $108.35 in 2025.
- 2022: $14.68
- 2023: $129.40
- 2024: $69.24
- 2025: $108.35
Sources: CMS Medicare Physician & Other Practitioners (2024), CMS Medicare Part D Prescribers (2024), CMS Open Payments (2025), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo · Report an error.
Pharma & Medical Device Financial Disclosures
Payments and other transfers of value that drug and medical device companies reported to CMS Open Payments
Program year 2025 (payments made January 1 – December 31, 2025): fewer than 11 records totaling $108.35.
| Manufacturer | Payment Nature | Product | Type | Amount ($) |
|---|---|---|---|---|
| Boston Scientific Corporation |
Food and Beverage
In-kind items and services
|
TheraSphere Y90 Glass Microspheres 10 GBq | General | $47.73 |
| Boston Scientific Corporation |
Food and Beverage
In-kind items and services
|
TheraSphere Y90 Glass Microspheres 10 GBq | General | $41.09 |
| Astellas Pharma US Inc |
Food and Beverage
In-kind items and services
|
Veozah | General | $19.53 |
Source: CMS Open Payments, program year 2025, released June 30, 2026.
Performed Procedures & Service Volume
CPT® is a registered trademark of the American Medical Association. CPT codes, descriptions and other data only are copyright 2016–2023 American Medical Association. All rights reserved. Applicable FARS/HHSARS apply. Descriptions of CPT codes are the AMA's CPT Consumer Friendly Descriptors as published by CMS in the Medicare Physician & Other Practitioners – by Provider and Service data, 2017–2024; they are plain-language summaries, not for clinical coding or documentation. HCPCS Level II codes and descriptions are from CMS. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.
| HCPCS Code | Services | Patients | Submitted Charge | Medicare Allowed |
|---|---|---|---|---|
|
99213
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more
|
75 | 65 | $244.00 | $75.09 |
|
99222
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes
|
41 | 41 | $367.00 | $103.46 |
|
99221
Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes
|
28 | 28 | $273.00 | $67.00 |
|
99204
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more
|
15 | 15 | $438.40 | $137.83 |
Source: CMS Part B by Provider and Service, 2024; services under 11 beneficiaries omitted by CMS. Privacy limits
Submitted charges are billed amounts, not a price quote for your visit.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Hydrocodone-Acetaminophen | Hydrocodone/Acetaminophen | 14 | 99 | $113.46 | 13 |
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
Self-certified to NPPES: 2024-04-24NUCC Taxonomy Code: 363A00000X
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - PHYSICIAN ASSISTANT
I20161130002406
VA
7315077062
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
Clinicians Sharing This Practice Address or Phone
Clinicians sharing this NPPES address, phone or fax; a shared contact does not mean they work together.
Orthopaedic Surgery
Doctor of Medicine (M.D.)
Orthopaedic Surgery
Doctor of Medicine (M.D.)
Physician Assistant - Medical
Career & Practice History Timeline
Changes recorded in monthly NPPES data files: addresses, names, credentials, specialties and NPI status
Registered at 220 CAMPUS BLVD STE 210, WINCHESTER, VA 226012889 (Tel: 5405365100)
Physician Assistant (license number reported to NPPES: VA 0110005462)
Registered at 1870 AMHERST ST STE C, WINCHESTER, VA 226012841 (Tel: 5405360153)
Registered at 220 CAMPUS BLVD STE 100, WINCHESTER, VA 226012888 (Tel: 5405365100)
Registered at 3918 CENTREVILLE RD, CHANTILLY, VA 201513224 (Tel: 7036576925)
Registered at 5000 COX RD, GLEN ALLEN, VA 230609263 (Tel: 8049685700)
NPI status registered as active in NPPES database
Registered at 5000 COX RD, GLEN ALLEN, VA 230609263 (Tel: 7855642820)
Registered at 24149 STATESBORO PL, ASHBURN, VA 201481775 (Tel: 7855642820)
Recorded as JOHN WALKER, MPAS, DSC, APA-C
Physician Assistant (license number reported to NPPES: VA 0110005462)
First registered as active Individual Practitioner in NPPES Database.
NPI Administrative Meta
Other Physician Assistants in Winchester
- Ava Danier, PA
- Hannah Vanrooyen, PA-C
- Megan Collins, PA-C
- Victoria Rohrer
- Laura Scheller, PA
- Shannon Wuerthele
Mailing Address
220 Campus Blvd Ste 210
Winchester, VA 226012889
Phone: 5405365100