NPI registry status
Active
2026 NPPES data Nephrology Physician NPI 1588847362 M.D.
Verify on CMS → Michael Yap, M.D.
Nephrology Physician in Orange, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 10,806 in Nephrology 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
425
Medicare Part D claims · 79 beneficiaries · Nephrology Physician avg: 2K
Generic prescribing
77%
generic claims · 23% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$102.04
5 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Michael Yap, M.D. filed 425 Medicare Part D claims in 2024 as a Nephrology Physician in Orange, California, prescribing 77% generic.
- 425
- Part D claims, 2024
- 77%
- generic prescribing
- $102.04
- industry payments (Sunshine Act)
- ≥61st
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about Michael Yap, M.D.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1588847362), first enumerated 12/14/2007.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 425 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Practices in an ABMS-board-eligible specialty; board certification not confirmed in federal records.
- Reported
Industry payment transparency
$102.04 in reported industry payments (5 transfers) in 2024 under the federal Sunshine Act — disclosed transfers of value, not a quality rating.
Source: CMS Open Payments
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not Michael Yap, M.D.'s individual license status. Verify directly with the state medical board.
Source: MBC annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1588847362 · Nephrology Physician
NPI-10 · ENUM-MID · TAX-MID · RX-LIGHT · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1588847362
- ENUM-MID 2007
- TAX-MID 11K Nephrology Physician
- RX-LIGHT 425
- BOOK-LIGHT 1,165 in California
- PHOTO-ENUM Michael Lattanzio, D… · 2007
Michael Yap, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
425 ≥ 61st percentile 61% of 1,416,883 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
◑
Board-eligible specialty (heuristic, not verified)
Michael Yap, M.D. 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 Michael Yap, M.D.?
Quality data not reportedPrimary specialty
Nephrology Physician
Medicare Part D claims
425 72% vs specialty avg
Specialty distribution in California
How Nephrology Physician compares to other specialties among California 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 Nephrology 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).
Practice Address
Provider Details
| NPI | 1588847362 |
|---|---|
| Specialty | Nephrology Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 12/14/2007 |
Industry payments received (2024) - CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for Michael Yap, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$102
Largest payer
OPKO Pharmaceuticals, LLC
Most common payment type
Food and Beverage
Industry payments are not necessarily indicators of bias, they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Michael Yap, M.D.. To verify Michael Yap, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Typical
Michael Yap, M.D. - brand share 23.0%
Nephrology Physician average
23% brand-name claims vs 77% generic, on 425 2024 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 2024.
425
Total Claims
$312K
Total Drug Cost
79
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 759.433
- Total Day Supply
- 21,785
- Brand vs Generic
- 23% brand / 77% generic
- Brand Drug Cost
- $147K
- Generic Drug Cost
- $165K
Patient Demographics
- Average Patient Age
- 70.4 years
- Avg HCC Risk Score
- 4.49
- Gender Split
- 41% female / 59% male
- Age Distribution
- <65: 20, 65-74: 25, 75-84: 19, 85+: 15
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Michael Yap, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Nifedipine Er
Nifedipine Er
41 claims
- Tolvaptan
Tolvaptan
36 claims
- Bumetanide
Bumetanide
33 claims
- Valsartan
Valsartan
29 claims
- Auryxia
Auryxia
18 claims
- Prosol
Prosol
18 claims
- Amlodipine Besylate
Amlodipine Besylate
17 claims
- Furosemide
Furosemide
17 claims
| Drug | Claims |
|---|---|
| Nifedipine Er Nifedipine | 41 |
| Tolvaptan | 36 |
| Bumetanide | 33 |
| Valsartan | 29 |
| Auryxia Ferric Citrate | 18 |
| Prosol Parenteral Amino Acid 20% No.1 | 18 |
| Amlodipine Besylate | 17 |
| Furosemide | 17 |
| Calcitriol | 15 |
| Clinolipid Fat Emulsion/Olive/Soy/Phospho | 12 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Nephrology Physician Overview
How Michael Yap, M.D. fits within the Nephrology Physician landscape nationally.
10,806
Nephrology Physician Providers in US
55
States with Nephrology Physician
1,511
Avg Claims per Provider
Michael Yap, M.D.'s 425 claims are below the specialty average of 1,511.
Nationwide Nephrology Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Yap, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2007)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Nephrology Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Yap.
One of 1,165 Nephrology Physician providers enrolled in California, 5 are shown here.
Dr. Antoine Abcar
MD
Los Angeles, CA
Dr. Basmah Abdalla
M.D.
Los Angeles, CA
Dr. Omaran Abdeen
M.D.
Mission Hills, CA
Dr. Anas Abou-Ismail
MD
Palm Springs, CA
Dr. Sreedhar Adapa
M.D.
Visalia, CA
Compare Nephrology Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Michael Yap, M.D.'s specialty? ▼
Michael Yap, M.D. specializes in Nephrology Physician and practices in Orange, California. Credentials: M.D..
How much does Michael Yap, M.D. prescribe under Medicare Part D? ▼
In 2024, Michael Yap, M.D. wrote 425 Medicare Part D claims totaling $312K in drug costs for 79 beneficiaries.
Where is Michael Yap, M.D. located? ▼
Michael Yap, M.D. is located at 500 S MAIN ST STE 101, Orange, CA, 92868. Phone: (657) 231-2099.
What is Michael Yap, M.D.'s NPI number? ▼
Michael Yap, M.D.'s National Provider Identifier (NPI) is 1588847362, issued on 12/14/2007.
Does Michael Yap, M.D. prescribe more brand-name or generic drugs? ▼
Michael Yap, M.D.'s prescribing is 23% brand-name and 77% generic drugs by claim count, with $147K in brand drug costs.
How many Nephrology Physician providers are there in the US? ▼
There are 10,806 Nephrology Physician providers across 55 states in the US. The average Nephrology Physician provider writes 1,511 Medicare Part D claims per year.
What drugs does Michael Yap, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Michael Yap, M.D.'s most frequently prescribed drugs include Nifedipine Er, Tolvaptan, Bumetanide. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Michael Yap, M.D. accept Medicare? ▼
Michael Yap, M.D. appears in CMS Medicare data with 425 Part D claims and 79 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Michael Yap, M.D.'s credentials? ▼
Michael Yap, M.D.'s NPI is 1588847362 with credentials M.D.. 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 (2024). 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 August 2026 (NPPES) / 2024 (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
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 August 2026.