NPI registry status
Active
2026 NPPES data Rheumatology Physician NPI 1154364214 MD
Verify on CMS → James Posever, MD
Rheumatology Physician in Phoenix, 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 6,200 in Rheumatology 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
727
Medicare Part D claims · 79 beneficiaries · Rheumatology Physician avg: 2K
Generic prescribing
65%
generic claims · 34% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
James Posever, MD filed 727 Medicare Part D claims in 2023 as a Rheumatology Physician in Phoenix, Arizona, prescribing 65% generic.
- 727
- Part D claims, 2023
- 65%
- generic prescribing
- Likely
- board-certified (heuristic)
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.
James Posever, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
727 Top 29% higher than 71% 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 certification likely (heuristic, not verified)
James Posever, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 2 hospital affiliations - signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about James Posever, MD?
Quality data not reportedPrimary specialty
Rheumatology Physician
Medicare Part D claims
727 65% vs specialty avg
Specialty distribution in Arizona
How Rheumatology 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 Rheumatology 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).
James Posever, MD appears in the CMS NPPES registry as a Rheumatology Physician provider holding MD credentials at 4212 N 16TH ST, Phoenix, AZ, 85016, with a listed phone of (602) 263-1200. NPI 1154364214 was issued on 06/14/2006.
Medicare Part D records for calendar year 2023 show 727 prescription claims written by this provider, covering 79 Medicare beneficiaries and totaling roughly $880K in drug spend, split 34% brand-name and 65% generic by claim count.
Rheumatology Physician is a mid-sized specialty nationwide, with 6,200 enrolled providers across 52 states and an average of 2,054 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 | 1154364214 |
|---|---|
| Specialty | Rheumatology Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 06/14/2006 |
Hospital and facility affiliations
Facilities where James Posever, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Dhew Ind Hlth SV Hlth Svs And Mntl Hlth Adm
Phoenix, AZ
Dhhs Phs Ihs Phoenix Area
Winterhaven, CA
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Brand vs generic prescribing mix · Above average
James Posever, MD - brand share 34.0%
Rheumatology Physician average
34% brand-name claims vs 65% generic, on 727 2023 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
727
Total Claims
$880K
Total Drug Cost
79
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,511
- Total Day Supply
- 44,754
- Brand vs Generic
- 34% brand / 65% generic
- Brand Drug Cost
- $858K
- Generic Drug Cost
- $21K
Patient Demographics
- Average Patient Age
- 65.8 years
- Avg HCC Risk Score
- 2.06
- Age Distribution
- <65: 28, 65-74: 33, 75-84: N/A, 85+: N/A
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What James Posever, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Hydroxychloroquine…
Hydroxychloroquine Sulfate
109 claims
- Enbrel Sureclick
Enbrel Sureclick
65 claims
- Sulfasalazine
Sulfasalazine
55 claims
- Methotrexate
Methotrexate
45 claims
- Meloxicam
Meloxicam
44 claims
- Ibuprofen 32
Ibuprofen
32 claims
- Celecoxib 28
Celecoxib
28 claims
- Rinvoq 21
Rinvoq
21 claims
| Drug | Claims |
|---|---|
| Hydroxychloroquine Sulfate | 109 |
| Enbrel Sureclick Etanercept | 65 |
| Sulfasalazine | 55 |
| Methotrexate Methotrexate Sodium | 45 |
| Meloxicam | 44 |
| Ibuprofen | 32 |
| Celecoxib | 28 |
| Rinvoq Upadacitinib | 21 |
| Mycophenolate Mofetil | 20 |
| Potassium Chloride | 14 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Rheumatology Physician Overview
How James Posever, MD fits within the Rheumatology Physician landscape nationally.
6,200
Rheumatology Physician Providers in US
52
States with Rheumatology Physician
2,054
Avg Claims per Provider
James Posever, MD's 727 claims are below the specialty average of 2,054.
Nearby Rheumatology Physician Providers in Arizona
Other clinicians with the same primary specialty enrolled in Arizona, drawn from the same CMS NPPES roster as Posever.
Dr. Orwah Al-Khalili
MD
Peoria, AZ
Dr. Amer Al-Khoudari
M.D.
Chandler, AZ
Dr. Mona Amin
D.O.
Glendale, AZ
Dr. Madhu Arora
MD
Yuma, AZ
Dr. Jeanne Attrep
M.D.
Phoenix, AZ
Compare Rheumatology Physician nationally: see state-by-state distribution →
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 Rheumatology 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.
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Frequently Asked Questions
What is James Posever, MD's specialty? ▼
James Posever, MD specializes in Rheumatology Physician and practices in Phoenix, Arizona. Credentials: MD.
How much does James Posever, MD prescribe under Medicare Part D? ▼
In 2023, James Posever, MD wrote 727 Medicare Part D claims totaling $880K in drug costs for 79 beneficiaries.
Where is James Posever, MD located? ▼
James Posever, MD is located at 4212 N 16TH ST, Phoenix, AZ, 85016. Phone: (602) 263-1200.
What is James Posever, MD's NPI number? ▼
James Posever, MD's National Provider Identifier (NPI) is 1154364214, issued on 06/14/2006.
Does James Posever, MD prescribe more brand-name or generic drugs? ▼
James Posever, MD's prescribing is 34% brand-name and 65% generic drugs by claim count, with $858K in brand drug costs.
How many Rheumatology Physician providers are there in the US? ▼
There are 6,200 Rheumatology Physician providers across 52 states in the US. The average Rheumatology Physician provider writes 2,054 Medicare Part D claims per year.
What drugs does James Posever, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, James Posever, MD's most frequently prescribed drugs include Hydroxychloroquine Sulfate, Enbrel Sureclick, Sulfasalazine. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does James Posever, MD accept Medicare? ▼
James Posever, MD appears in CMS Medicare data with 727 Part D claims and 79 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify James Posever, MD's credentials? ▼
James Posever, MD's NPI is 1154364214 with credentials MD. 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.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 2026.