NPI registry status
Active
2026 NPPES data Family Medicine Physician NPI 1811282650 M.D.
Verify on CMS → Rainbow Chung-Ou, M.D.
Family Medicine Physician in Chino Hills, 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 150,125 in Family 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
7K
Medicare Part D claims · 459 beneficiaries · Family Medicine Physician avg: 4K
Generic prescribing
90%
generic claims · 9% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$559.95
24 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Rainbow Chung-Ou, M.D. filed 6,889 Medicare Part D claims in 2024 as a Family Medicine Physician in Chino Hills, California, prescribing 90% generic.
- 7K
- Part D claims, 2024
- 90%
- generic prescribing
- $559.95
- industry payments (Sunshine Act)
- ≥96th
- 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 Rainbow Chung-Ou, 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 1811282650), first enumerated 06/09/2011.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 6,889 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
$559.95 in reported industry payments (24 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 Rainbow Chung-Ou, 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 1811282650 · Family Medicine Physician
NPI-10 · ENUM-MID · TAX-MEGA · RX-MID · BOOK-MID · PHOTO-ENUM
- NPI-10 1811282650
- ENUM-MID 2011
- TAX-MEGA 150K Family Medicine
- RX-MID 6,889
- BOOK-MID 16,272 in California
- PHOTO-ENUM Shyam Goverdhana · 2011
Rainbow Chung-Ou, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
6,889 ≥ 96th percentile 96% 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)
Rainbow Chung-Ou, 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 Rainbow Chung-Ou, M.D.?
Quality data not reportedPrimary specialty
Family Medicine Physician
Medicare Part D claims
6,889 96% vs specialty avg
Specialty distribution in California
How Family Medicine 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 Family 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).
Practice Address
Provider Details
| NPI | 1811282650 |
|---|---|
| Specialty | Family Medicine Physician |
| Credentials | M.D. |
| Gender | Female |
| NPI Issued | 06/09/2011 |
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 Rainbow Chung-Ou, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$560
Largest payer
PFIZER INC.
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 Rainbow Chung-Ou, M.D.. To verify Rainbow Chung-Ou, 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 · Generic-heavy
Rainbow Chung-Ou, M.D. - brand share 9.0%
Family Medicine Physician average
9% brand-name claims vs 90% generic, on 6,889 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.
6,889
Total Claims
$509K
Total Drug Cost
459
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 15,079.333
- Total Day Supply
- 441,113
- Brand vs Generic
- 9% brand / 90% generic
- Brand Drug Cost
- $380K
- Generic Drug Cost
- $125K
- Opioid Claims
- 286 (4.2% rate)
- Antibiotic Claims
- 151
Patient Demographics
- Average Patient Age
- 72.8 years
- Avg HCC Risk Score
- 1.17
- Gender Split
- 60% female / 40% male
- Age Distribution
- <65: 29, 65-74: 259, 75-84: 133, 85+: 38
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Rainbow Chung-Ou, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2024
- Atorvastatin Calcium
Atorvastatin Calcium
445 claims
- Amlodipine Besylate
Amlodipine Besylate
256 claims
- Metformin Hcl
Metformin Hcl
252 claims
- Losartan Potassium
Losartan Potassium
219 claims
- Lisinopril
Lisinopril
201 claims
- Simvastatin
Simvastatin
183 claims
- Hydrocodone-Acetam… 176
Hydrocodone-Acetaminophen
176 claims
- Omeprazole 172
Omeprazole
172 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 445 |
| Amlodipine Besylate | 256 |
| Metformin Hcl | 252 |
| Losartan Potassium | 219 |
| Lisinopril | 201 |
| Simvastatin | 183 |
| Hydrocodone-Acetaminophen Hydrocodone/Acetaminophen | 176 |
| Omeprazole | 172 |
| Tamsulosin Hcl | 158 |
| Levothyroxine Sodium | 148 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Family Medicine Physician Overview
How Rainbow Chung-Ou, M.D. fits within the Family Medicine Physician landscape nationally.
150,125
Family Medicine Physician Providers in US
56
States with Family Medicine Physician
3,519
Avg Claims per Provider
Rainbow Chung-Ou, M.D.'s 6,889 claims are above the specialty average of 3,519.
Nationwide Family Medicine Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Chung-Ou, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2011)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Family Medicine Physician Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Chung-Ou.
One of 16,272 Family Medicine Physician providers enrolled in California, 5 are shown here.
Dr. Omer Aba-Omer
MD
Santa Monica, CA
Dr. Michelle Ababa
MD
Wilmington, CA
Dr. Anna Tzeitel Abalos
MD
Roseville, CA
Dr. Adan Abarca
MD
Anaheim, CA
Dr. Vanessa Abarca
DO
Ventura, CA
Compare Family Medicine Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Rainbow Chung-Ou, M.D.'s specialty? ▼
Rainbow Chung-Ou, M.D. specializes in Family Medicine Physician and practices in Chino Hills, California. Credentials: M.D..
How much does Rainbow Chung-Ou, M.D. prescribe under Medicare Part D? ▼
In 2024, Rainbow Chung-Ou, M.D. wrote 6,889 Medicare Part D claims totaling $509K in drug costs for 459 beneficiaries.
Where is Rainbow Chung-Ou, M.D. located? ▼
Rainbow Chung-Ou, M.D. is located at 4195 CHINO HILLS PKWY STE H, Chino Hills, CA, 91709. Phone: (909) 597-7817.
What is Rainbow Chung-Ou, M.D.'s NPI number? ▼
Rainbow Chung-Ou, M.D.'s National Provider Identifier (NPI) is 1811282650, issued on 06/09/2011.
Does Rainbow Chung-Ou, M.D. prescribe more brand-name or generic drugs? ▼
Rainbow Chung-Ou, M.D.'s prescribing is 9% brand-name and 90% generic drugs by claim count, with $380K in brand drug costs.
Does Rainbow Chung-Ou, M.D. prescribe opioids? ▼
Yes, Rainbow Chung-Ou, M.D. had 286 opioid claims in 2024 with an opioid prescribing rate of 4.2%.
How many Family Medicine Physician providers are there in the US? ▼
There are 150,125 Family Medicine Physician providers across 56 states in the US. The average Family Medicine Physician provider writes 3,519 Medicare Part D claims per year.
What drugs does Rainbow Chung-Ou, M.D. prescribe most often? ▼
Based on 2024 Medicare Part D data, Rainbow Chung-Ou, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Metformin Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Rainbow Chung-Ou, M.D. accept Medicare? ▼
Rainbow Chung-Ou, M.D. appears in CMS Medicare data with 6,889 Part D claims and 459 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Rainbow Chung-Ou, M.D.'s credentials? ▼
Rainbow Chung-Ou, M.D.'s NPI is 1811282650 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.