NPI registry status
Active
2026 NPPES data Addiction Medicine (Preventive Medicine) Physician NPI 1427542927
Verify on CMS → William Fox Jr
Addiction Medicine (Preventive Medicine) Physician in Litchfield Park, Arizona.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 325 in Addiction Medicine (Preventive Medicine) Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
97
Medicare Part D claims · 19 beneficiaries · Addiction Medicine (Preventive Medicine) Physician avg: 959
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
William Fox Jr filed 97 Medicare Part D claims in 2023 as a Addiction Medicine (Preventive Medicine) Physician in Litchfield Park, Arizona.
- 97
- Part D claims, 2023
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
William Fox Jr's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
97 0th percentile higher than 0% of 1,370,886 prescribers
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source CMS Medicare Part D Prescriber Public Use File · 2023
◑
Board-eligible specialty (heuristic, not verified)
William Fox Jr practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about William Fox Jr?
Quality data not reportedPrimary specialty
Addiction Medicine (Preventive Medicine) Physician
Medicare Part D claims
97 90% vs specialty avg
Specialty distribution in Arizona
How Addiction Medicine (Preventive Medicine) Physician compares to other specialties among Arizona providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Addiction Medicine (Preventive Medicine) Physician. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
William Fox Jr appears in the CMS NPPES registry as a Addiction Medicine (Preventive Medicine) Physician provider at 19590 W SAN MIGUEL AVE, Litchfield Park, AZ, 85340, with a listed phone of (623) 377-0825. NPI 1427542927 was issued on 06/18/2018.
Medicare Part D records for calendar year 2023 show 97 prescription claims written by this provider, covering 19 Medicare beneficiaries and totaling roughly $3K in drug spend.
Addiction Medicine (Preventive Medicine) Physician is a narrow specialty nationwide, with 325 enrolled providers across 44 states and an average of 959 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline.
Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist, always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.
Practice Address
Provider Details
| NPI | 1427542927 |
|---|---|
| Specialty | Addiction Medicine (Preventive Medicine) Physician |
| Gender | Male |
| NPI Issued | 06/18/2018 |
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
97
Total Claims
$3K
Total Drug Cost
19
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 103
- Total Day Supply
- 2,044
- Generic Drug Cost
- $3K
Patient Demographics
- Average Patient Age
- 56.6 years
- Avg HCC Risk Score
- 1.99
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
| Drug | Claims |
|---|---|
| Buprenorphine-Naloxone Buprenorphine Hcl/Naloxone Hcl | 51 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Addiction Medicine (Preventive Medicine) Physician in AZ →
All providers in Arizona →
Compare specialties →
Addiction Medicine (Preventive Medicine) Physician Overview
How William Fox Jr fits within the Addiction Medicine (Preventive Medicine) Physician landscape nationally.
325
Addiction Medicine (Preventive Medicine) Physician Providers in US
44
States with Addiction Medicine (Preventive Medicine) Physician
959
Avg Claims per Provider
William Fox Jr's 97 claims are below the specialty average of 959.
Nearby Addiction Medicine (Preventive Medicine) Physician Providers in Arizona
Other clinicians with the same primary specialty enrolled in Arizona, drawn from the same CMS NPPES roster as Fox Jr.
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Arizona medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Addiction Medicine (Preventive Medicine) Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
Healthcare Guides
Learn more about finding, verifying, and understanding healthcare providers.
How to Find a Doctor
Step-by-step guide to choosing a provider
Verify Credentials
Check NPI, board certification & license status
Medical Specialties Explained
Who treats what and how specialties differ
Understanding Medicare Claims Data
What prescribing data reveals about a provider
In-Network vs Out-of-Network
How insurance networks affect your costs
Telehealth Guide
Virtual care options and coverage in 2026
Explore Arizona
Frequently Asked Questions
What is William Fox Jr's specialty? ▼
William Fox Jr specializes in Addiction Medicine (Preventive Medicine) Physician and practices in Litchfield Park, Arizona.
How much does William Fox Jr prescribe under Medicare Part D? ▼
In 2023, William Fox Jr wrote 97 Medicare Part D claims totaling $3K in drug costs for 19 beneficiaries.
Where is William Fox Jr located? ▼
William Fox Jr is located at 19590 W SAN MIGUEL AVE, Litchfield Park, AZ, 85340. Phone: (623) 377-0825.
What is William Fox Jr's NPI number? ▼
William Fox Jr's National Provider Identifier (NPI) is 1427542927, issued on 06/18/2018.
How many Addiction Medicine (Preventive Medicine) Physician providers are there in the US? ▼
There are 325 Addiction Medicine (Preventive Medicine) Physician providers across 44 states in the US. The average Addiction Medicine (Preventive Medicine) Physician provider writes 959 Medicare Part D claims per year.
What drugs does William Fox Jr prescribe most often? ▼
Based on 2023 Medicare Part D data, William Fox Jr's most frequently prescribed drugs include Buprenorphine-Naloxone. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does William Fox Jr accept Medicare? ▼
William Fox Jr appears in CMS Medicare data with 97 Part D claims and 19 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify William Fox Jr's credentials? ▼
William Fox Jr's NPI is 1427542927. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Compiled from official public sources by the PlainDoctor editorial team.