NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1528041621 M.D.
Verify on CMS → Sally Chang, M.D.
Internal Medicine Physician in Kailua, Hawaii.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,737 in Internal 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
1K
Medicare Part D claims · 186 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
86%
generic claims · 13% 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
Sally Chang, M.D. filed 1,396 Medicare Part D claims in 2023 as a Internal Medicine Physician in Kailua, Hawaii, prescribing 86% generic.
- 1K
- Part D claims, 2023
- 86%
- generic prescribing
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.
Sally Chang, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,396 Top 21% higher than 79% 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)
Sally Chang, 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 Sally Chang, M.D.?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
1,396 49% vs specialty avg
Specialty distribution in Hawaii
How Internal Medicine Physician compares to other specialties among Hawaii 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 Internal 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).
Sally Chang, M.D. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding M.D. credentials at 407 ULUNIU ST STE 313, Kailua, HI, 96734, with a listed phone of (808) 261-3364. NPI 1528041621 was issued on 11/22/2005.
Medicare Part D records for calendar year 2023 show 1,396 prescription claims written by this provider, covering 186 Medicare beneficiaries and totaling roughly $220K in drug spend, split 13% brand-name and 86% generic by claim count.
Internal Medicine Physician is a high-volume specialty nationwide, with 172,737 enrolled providers across 56 states and an average of 2,716 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 | 1528041621 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D. |
| Gender | Female |
| NPI Issued | 11/22/2005 |
Brand vs generic prescribing mix · Typical
Sally Chang, M.D. - brand share 13.0%
Internal Medicine Physician average
13% brand-name claims vs 86% generic, on 1,396 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.
1,396
Total Claims
$220K
Total Drug Cost
186
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 3,958
- Total Day Supply
- 117,810
- Brand vs Generic
- 13% brand / 86% generic
- Brand Drug Cost
- $168K
- Generic Drug Cost
- $51K
- Antibiotic Claims
- 14
Patient Demographics
- Average Patient Age
- 78.5 years
- Avg HCC Risk Score
- 1.38
- Gender Split
- 74% female / 26% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Sally Chang, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
175 claims
- Levothyroxine Sodium
Levothyroxine Sodium
91 claims
- Simvastatin
Simvastatin
85 claims
- Irbesartan
Irbesartan
72 claims
- Amlodipine Besylate 69
Amlodipine Besylate
69 claims
- Metformin Hcl 62
Metformin Hcl
62 claims
- Lisinopril 59
Lisinopril
59 claims
- Losartan Potassium 55
Losartan Potassium
55 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 175 |
| Levothyroxine Sodium | 91 |
| Simvastatin | 85 |
| Irbesartan | 72 |
| Amlodipine Besylate | 69 |
| Metformin Hcl | 62 |
| Lisinopril | 59 |
| Losartan Potassium | 55 |
| Ramipril | 51 |
| Hydrochlorothiazide | 34 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Internal Medicine Physician Overview
How Sally Chang, M.D. fits within the Internal Medicine Physician landscape nationally.
172,737
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider
Sally Chang, M.D.'s 1,396 claims are below the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Hawaii
Other clinicians with the same primary specialty enrolled in Hawaii, drawn from the same CMS NPPES roster as Chang.
Dr. Michael Abdo
M.D.
Ewa Beach, HI
Dr. Carlos Abeyta
MD
Hilo, HI
Dr. Harry Acuna
MD
Waipahu, HI
Dr. Dale Adams
MD
Kailua, HI
Dr. Kevin Adams
MD
Honolulu, HI
Compare Internal Medicine 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 Hawaii medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Internal 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.
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Frequently Asked Questions
What is Sally Chang, M.D.'s specialty? ▼
Sally Chang, M.D. specializes in Internal Medicine Physician and practices in Kailua, Hawaii. Credentials: M.D..
How much does Sally Chang, M.D. prescribe under Medicare Part D? ▼
In 2023, Sally Chang, M.D. wrote 1,396 Medicare Part D claims totaling $220K in drug costs for 186 beneficiaries.
Where is Sally Chang, M.D. located? ▼
Sally Chang, M.D. is located at 407 ULUNIU ST STE 313, Kailua, HI, 96734. Phone: (808) 261-3364.
What is Sally Chang, M.D.'s NPI number? ▼
Sally Chang, M.D.'s National Provider Identifier (NPI) is 1528041621, issued on 11/22/2005.
Does Sally Chang, M.D. prescribe more brand-name or generic drugs? ▼
Sally Chang, M.D.'s prescribing is 13% brand-name and 86% generic drugs by claim count, with $168K in brand drug costs.
How many Internal Medicine Physician providers are there in the US? ▼
There are 172,737 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does Sally Chang, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Sally Chang, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Levothyroxine Sodium, Simvastatin. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Sally Chang, M.D. accept Medicare? ▼
Sally Chang, M.D. appears in CMS Medicare data with 1,396 Part D claims and 186 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Sally Chang, M.D.'s credentials? ▼
Sally Chang, M.D.'s NPI is 1528041621 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 (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.