Physician Profile
Tony S. Chang, MD
Unclaimed ProfileAbout Dr. Chang
Tony S. Chang, MD is a healthcare provider in Madison, WI specializing in internal medicine. Tony trained at University of Wisconsin School of Medicine, graduating in 1995. According to Medicare claims data, Tony cared for 822 Medicare patients across 1,064 services. The services billed most often include visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient', insertion of needle into vein for collection of blood sample, and established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it — free, and no identity document with a practice or institutional email.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (608) 287-2440
- Email not available
Practice Locations
20 S PARK ST SUITE 405B
Madison, WI 53715
Conditions Commonly Evaluated or Treated
Within Internal Medicine generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
Cardiometabolic
Digestive and liver
Endocrine, blood, and bone
Infectious disease
Kidney and urinary
Respiratory
Blood & Circulation
Blood disorders
Brain & Nerves
Brain and nerves
Cardiac and vascular
Digestive
Heart & Circulation
Infections
Kidney & Bladder
Lungs & Breathing
Mental Health
Neurologic and behavioral
Pain
Rheumatologic and pain
Procedures & services
Most searched procedures
Preventive and evaluation
Screening and diagnostic testing
Bones & Joints
Brain and nerves
Cancer screening
Digestive
Exams & Consultations
Heart & Circulation
Heart health
Imaging referral
Immunizations
Lab tests
Lungs & Breathing
Metabolic & Weight
Minor procedures
Office procedures
Office Procedures
Pain management
Preventive & Routine Care
Screenings & Diagnostics
Sexual health
Procedures Most Often Billed to Medicare
1,064 services · 822 patients · 12 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Insertion of needle into vein for collection of blood sample | Procedure | 36415 |
242 | More often than most peers in Internal Medicine |
| Sarscov2 vac 50 mcg/0.5ml im | Treatment | 91322 |
37 | More often than most peers in Internal Medicine |
| Admn sarscov2 vacc 1 dose | Treatment | 90480 |
37 | More often than most peers in Internal Medicine |
| Influenza vaccine, inactivated | Treatment | 90653 |
27 | As often as other peers in Internal Medicine |
| Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient' | Billing code | G2211 |
293 | More often than most peers in Internal Medicine |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
160 | As often as other peers in Internal Medicine |
| Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more | Office visit | 99213 |
103 | As often as other peers in Internal Medicine |
| Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more | Office visit | 99215 |
87 | More often than most peers in Internal Medicine |
| Administration of influenza virus vaccine | Billing code | G0008 |
32 | As often as other peers in Internal Medicine |
| Automated urinalysis test | Lab test | 81003 |
17 | Less often than most peers in Internal Medicine |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other internists at this location 2
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 8
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 30 related providers in 4 groups
Other internists in Madison 7
Same specialty, same city.
Trained at University of Wisconsin School of Medicine 7
Other providers in the same specialty who trained at the same institution.
Class of 1995 at University of Wisconsin School of Medicine 8
Providers who graduated from the same medical school in the same year.
Also performs Insertion of needle into vein for collection of blood sample 8
Providers in WI who bill this service to Medicare most often.
Common questions
What kind of doctor is Dr. Chang?
Dr. Chang is an internist in Madison, WI. That is the designation recorded for this NPI in the federal registry, where it is listed as “Internal Medicine”.
NPI registry
What is Dr. Chang's address?
Dr. Chang is listed at 20 S Park St Suite 405B, Madison, WI 53715. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. Chang?
The number on file is (608) 287-2440. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Chang's NPI number?
Dr. Chang's National Provider Identifier is 1831166990. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Chang train?
Dr. Chang attended University of Wisconsin School of Medicine, graduating in 1995. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Chang been practicing?
Dr. Chang has 31 years experience. Calculated from a graduation year of 1995, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. Chang perform?
According to Medicare billing data, Dr. Chang performs procedures including insertion of needle into vein for collection of blood sample; provides treatments such as sarscov2 vac 50 mcg/0.5ml im and admn sarscov2 vacc 1 dose, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Chang confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Chang. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.