NPI registry status
Active
2026 NPPES data Hospitalist Physician NPI 1598227068 MD
Verify on CMS → Carolyn Cao, MD
Hospitalist Physician in Chicago, Illinois.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,825 in Hospitalist 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
266
Medicare Part D claims · 34 beneficiaries · Hospitalist Physician avg: 888
Industry payments
$235.36
2 payments · CMS Open Payments (Sunshine Act)
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Carolyn Cao, MD filed 266 Medicare Part D claims in 2023 as a Hospitalist Physician in Chicago, Illinois.
- 266
- Part D claims, 2023
- 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.
Carolyn Cao, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
266 49th percentile higher than 49% 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)
Carolyn Cao, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - 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 Carolyn Cao, MD?
Quality data not reportedPrimary specialty
Hospitalist Physician
Medicare Part D claims
266 70% vs specialty avg
Specialty distribution in Illinois
How Hospitalist Physician compares to other specialties among Illinois 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 Hospitalist 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).
Carolyn Cao, MD appears in the CMS NPPES registry as a Hospitalist Physician provider holding MD credentials at 539 N DEARBORN ST, Chicago, IL, 60654, with a listed phone of (312) 549-4400. NPI 1598227068 was issued on 04/03/2019.
Medicare Part D records for calendar year 2023 show 266 prescription claims written by this provider, covering 34 Medicare beneficiaries and totaling roughly $24K in drug spend.
Hospitalist Physician is a mid-sized specialty nationwide, with 16,825 enrolled providers across 54 states and an average of 888 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 | 1598227068 |
|---|---|
| Specialty | Hospitalist Physician |
| Credentials | MD |
| Gender | Female |
| NPI Issued | 04/03/2019 |
Hospital and facility affiliations
Facilities where Carolyn Cao, 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.
Rush University Medical Group
Chicago, IL
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
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 Carolyn Cao, MD. Source: openpaymentsdata.cms.gov.
Total received
$235
Largest payer
Novo Nordisk 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 - Illinois IDFPR 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 ~42K Illinois medical licensees in 2023 - they are NOT specific to Carolyn Cao, MD. To verify Carolyn Cao, MD's current license status, search the IDFPR public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
106
Total board actions, Illinois 2023
Across 103 cases
2.52
Actions per 1,000 licensees
Illinois statewide rate
probation
Most common action type
38 cases
IDFPR 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 Illinois disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
266
Total Claims
$24K
Total Drug Cost
34
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 362
- Total Day Supply
- 10,552
- Generic Drug Cost
- $5K
Patient Demographics
- Average Patient Age
- 62.7 years
- Avg HCC Risk Score
- 1.97
- Gender Split
- 44% female / 56% male
- Age Distribution
- <65: 15, 65-74: 14, 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 Carolyn Cao, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
28 claims
- Metformin Hcl
Metformin Hcl
17 claims
- Amlodipine Besylate
Amlodipine Besylate
16 claims
- Lisinopril
Lisinopril
15 claims
- Chlorthalidone
Chlorthalidone
13 claims
- Epinephrine
Epinephrine
13 claims
- Minoxidil
Minoxidil
13 claims
- Carvedilol 11
Carvedilol
11 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 28 |
| Metformin Hcl | 17 |
| Amlodipine Besylate | 16 |
| Lisinopril | 15 |
| Chlorthalidone | 13 |
| Epinephrine | 13 |
| Minoxidil | 13 |
| Carvedilol | 11 |
| Omeprazole | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Hospitalist Physician Overview
How Carolyn Cao, MD fits within the Hospitalist Physician landscape nationally.
16,825
Hospitalist Physician Providers in US
54
States with Hospitalist Physician
888
Avg Claims per Provider
Carolyn Cao, MD's 266 claims are below the specialty average of 888.
Nearby Hospitalist Physician Providers in Illinois
Other clinicians with the same primary specialty enrolled in Illinois, drawn from the same CMS NPPES roster as Cao.
Dr. Osamah Abdallah
M.D.
Maywood, IL
Sufyan Abdulmujeeb
Niles, IL
Dr. Eyad Abdulrazzak
MD
Evanston, IL
Dr. Gina Abraham
MD
Franklin Park, IL
Dr. Rebecca Abraham
PA-C
Chicago, IL
Compare Hospitalist 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 Illinois medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Hospitalist 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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Understanding Medicare Claims Data
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Frequently Asked Questions
What is Carolyn Cao, MD's specialty? ▼
Carolyn Cao, MD specializes in Hospitalist Physician and practices in Chicago, Illinois. Credentials: MD.
How much does Carolyn Cao, MD prescribe under Medicare Part D? ▼
In 2023, Carolyn Cao, MD wrote 266 Medicare Part D claims totaling $24K in drug costs for 34 beneficiaries.
Where is Carolyn Cao, MD located? ▼
Carolyn Cao, MD is located at 539 N DEARBORN ST, Chicago, IL, 60654. Phone: (312) 549-4400.
What is Carolyn Cao, MD's NPI number? ▼
Carolyn Cao, MD's National Provider Identifier (NPI) is 1598227068, issued on 04/03/2019.
How many Hospitalist Physician providers are there in the US? ▼
There are 16,825 Hospitalist Physician providers across 54 states in the US. The average Hospitalist Physician provider writes 888 Medicare Part D claims per year.
What drugs does Carolyn Cao, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Carolyn Cao, MD's most frequently prescribed drugs include Atorvastatin Calcium, Metformin Hcl, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Carolyn Cao, MD accept Medicare? ▼
Carolyn Cao, MD appears in CMS Medicare data with 266 Part D claims and 34 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Carolyn Cao, MD's credentials? ▼
Carolyn Cao, MD's NPI is 1598227068 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.