Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Alan W Chang, MD

Individual provider Specialist · NPI 1912992330

Dr. Alan W Chang, MD practises Gastroenterology in Doylestown, Pennsylvania. Qualified in 1998, 28 years ago. Practices with Via Affiliates, a 194-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Pennsylvania.

Years since qualifying
28
Licensed in
PA
In the registry since
2005
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

599 W State St Ste 200
Doylestown, PA 18901-2567
Phone: (215) 345-6050
Fax: (215) 345-6568
Show map & directions

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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence MD071986L (PA)
Specialist Taxonomy 174400000X · Licence MD071986L (PA)

Record details

NPI number1912992330
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedSeptember 12, 2005
Last updated in NPPESFebruary 28, 2020
Certification dateFebruary 28, 2020

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyGASTROENTEROLOGY
Also practisesINTERNAL MEDICINE
Medical schoolOTHER
Graduated 1998 (28 years in practice)
Group practice Via Affiliates — 194 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations2 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Colonoscopy 303 times · 97th percentile
Upper gastrointestinal (GI) endoscopy for acid reflux 200 times · 90th percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients673
Services billed 7,956 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $552 22 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Via Affiliates

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 194 clinicians in the practice; 12 are shown here.

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