Warren Chang, M.D.
NPI 1902888662 · Ophthalmology Physician · Bloomington, IN
Enrolled with Medicare as Practitioner - Ophthalmology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Warren Chang, M.D. is a Ophthalmology Physician provider in Bloomington, IN (NPI 1902888662).
Provider details
- NPI number
- 1902888662
- Entity type
- Individual
- Primary specialty
- Ophthalmology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- IN01052241 (IN)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
4,550 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Measurement of Corneal Curvature and Depth of Eye92136 | 732 | $37 |
| Injection of Drug Into Eye67028 | 707 | $109 |
| Removal of Cataract With Insertion of Prosthetic Lens66984 | 700 | $452 |
| Imaging of Retina92134 | 525 | $38 |
| Removal of Recurring Cataract in Lens Capsule Using a Laser66821 | 314 | $266 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 284 | $120 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 24 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Erythromycin Basebrand: Erythromycin | 272 | 193 |
| Latanoprost | 224 | 65 |
| Timolol Maleate | 135 | 36 |
| Tobramycin/Dexamethasonebrand: Tobramycin-Dexamethasone | 92 | 83 |
| Brimonidine Tartrate | 74 | 19 |
| Bimatoprostbrand: Lumigan | 66 | 23 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$777 across 27 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2005-11-17
- Last updated
- 2012-02-14
Frequently asked questions
- What is Warren Chang's NPI number?
- Warren Chang's National Provider Identifier (NPI) is 1902888662, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Warren Chang's specialty?
- Warren Chang is listed in the NPPES registry with a primary specialty of Ophthalmology Physician (Allopathic & Osteopathic Physicians).
- Where is Warren Chang located?
- Warren Chang's practice location on file with NPPES is 1011 W 2nd St, Bloomington, IN 47403-2216.
- What is Warren Chang's phone number?
- The practice phone number listed in the NPPES registry for Warren Chang is (812) 334-1213.
- Does Warren Chang accept Medicare?
- Warren Chang is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Warren Chang's NPI active?
- Yes — Warren Chang's NPI (1902888662) is active in the NPPES registry as of the last update on 2012-02-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.