Why are Medicare and Medicaid shown separately instead of combined?

They come from two different CMS data sources with no shared claim identifier, so they can't be reconciled into one number without double-counting or guessing. Every table and chart on this page keeps them fully separate.

Why is there no private/commercial revenue figure?

Private and commercial payer data comes from Transparency in Coverage files, which only publish negotiated rates — not claims or utilization volume. Without a volume figure, no revenue number can be computed for any provider from that data.

What does "Rank" mean in the Competitive Analysis & Benchmarks tables?

For a given CPT/HCPCS code, it's this provider's position by claims volume among all providers billing that same code at that geography level (State, National, or Indiana for Medicaid) — rank 1 means the highest claims volume for that code.

Why is the Medicaid comparison limited to Indiana only?

Medicaid is administered per-state with no single national fee schedule, so a state or national comparison the way Medicare has one isn't available. Indiana (this provider's own state) is the only grouping that's conceptually meaningful.

Why are the numbers rounded to the nearest 10?

To avoid implying more precision than the underlying data supports at a single-provider level. Ratios are kept precise since they're a relative comparison, not a volume or dollar figure.

How current is this data?

The Medicare and Medicaid tables are both single current snapshots, not refreshed on a recurring schedule yet.

Warren Chang (NPI 1902888662)

Field	Value
Entity Type	Individual
Organization	Warren Chang
Address	1011 W 2nd St
City	Bloomington
State	IN
ZIP	47403
Taxonomy	Ophthalmology Physician
NPI Enumerated	November 17, 2005

Payer Source	Total Paid
Medicare	$1.5M
Medicaid	$0

Key Findings

This provider’s commercial footprint in public payers is effectively single‑payer: lifetime Medicare revenue is $1.5M while there is no Medicaid billing on file, so the practice’s public-pay revenue exposure is concentrated in Medicare patients and fee schedules. That concentration means payer-mix shifts in Medicare policy would have outsized impact given the lack of Medicaid offset.

Medicare revenue is highly concentrated in a small set of ophthalmology services: the precomputed top three Medicare codes account for 84.4% of total Medicare revenue. Specifically, J0178 generates $975.7K (63.4% of Medicare revenue), 66984 generates $262.8K (17.1%), and 67028 generates $59K (3.8%), indicating a narrow set of procedures drive the bulk of income.

The code mix points to a combined retina and cataract surgical practice model: J0178 (aflibercept injection) and 67028 (intravitreal injections) represent anti‑VEGF/retina therapy activity while 66984 reflects standard cataract extraction with intraocular lens insertion. Volume counts reinforce this operational focus — 1.4K claims for J0178, 711 claims for 67028, and 728 claims for 66984 — suggesting routine, recurring injection throughput alongside a stable cataract surgery caseload.

Competitive standing on the top revenue codes looks modest rather than dominant nationally. J0178 ranks #885 of 3204 providers (72th percentile; typical, unremarkable volume), 66984 ranks #2342 of 15965 providers (85th percentile; typical, unremarkable volume), and 67028 ranks #1794 of 4255 providers (58th percentile; typical, unremarkable volume), so the provider is an established participant but not a national outlier in these high‑revenue procedures.

Ancillary diagnostic and procedure lines show pockets of above‑typical intensity that support the surgical and retina workstream: 92136 (biometry) has 756 claims and $21.9K revenue and ranks in the 97th percentile (notably above typical national volume), while 92134 (retinal imaging) has 524 claims and $14.7K revenue and ranks in the 87th percentile (typical, unremarkable volume). These high imaging and measurement volumes are consistent with a practice performing frequent cataract IOL calculations and retinal disease monitoring.

Office visit throughput is also elevated relative to peers, indicating substantial ambulatory clinic activity supporting procedural care: 99213 has 523 claims, $31.9K revenue and ranks in the 95th percentile (notably above typical national volume), and 99214 adds 348 claims with $27.5K revenue (82th percentile; typical, unremarkable volume). High E/M volumes combined with procedural coding suggest ongoing follow‑up and chronic disease management for established Medicare patients.

The provider’s tenure is long‑standing: NPI was enumerated 2005-11-17 (~21 years ago), which supports continuity of practice patterns and an established referral base for both cataract and retinal services. Long enumeration increases the likelihood that observed code mix reflects stable clinical focus rather than a transient billing pattern.

From a business‑risk perspective, the practice’s heavy reliance on a single high‑revenue drug code creates sensitivity to reimbursement or utilization shifts: J0178 alone accounts for $975.7K and 63.4% of Medicare revenue. Coupled with the absence of Medicaid revenue, changes to J0178 reimbursement, utilization, or product availability would materially affect overall Medicare revenue and the provider’s public‑payer stability.

Medicare: Complete Services Breakdown

The CPT/HCPCS codes generating the most Medicare revenue for this provider.

22 rows

CPT/HCPCS Code	Description	Claims	Avg Paid	Revenue
J0178	Injection, aflibercept, 1 mg	1,410	$690	$975.7K
66984	The provider inserts an artificial lens after removing an extracapsular cataract by aspiration or use of ultrasonic waves. This procedure is done without the use of an endoscopic laser probe to…	730	$360	$262.8K
67028	The provider injects a medication into the vitreous chamber of the eye as an isolated procedure or a separate procedure unrelated to any other procedure being performed on the eye.	710	$80	$59K
66821	The provider removes the haziness from the capsule of the eye using a laser for a patient with a secondary membranous cataract.	210	$210	$45.6K
J0585	Injection, onabotulinumtoxina, 1 unit	7,400	$10	$37K
99213	The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a low level of medical decision making, and/or the…	520	$60	$31.9K
99214	The provider sees an established patient for an office visit or other outpatient visit involving evaluation and management. The visit involves a moderate level of medical decision making, and/or the…	350	$80	$27.5K
92136	The provider uses a noninvasive method to measure the patient’s eye or eyes to get information that the provider then uses to calculate the appropriate power for an intraocular lens (IOL). Selecting…	760	$30	$21.9K
92134	The provider performs computerized diagnostic imaging of the retina in the posterior segment (back part) of the eye, interprets the data, and provides a report. The service may be on one or both eyes.	520	$30	$14.7K
67904	The provider repairs a drooping eyelid by tightening the levator muscle that controls eyelid movement to improve cosmetic appearance or remove the obstruction to a patient’s vision. He accesses the…	20	$670	$10K

Showing 1–10 of 22

Medicare: Competitive Analysis & Benchmarks

How this provider's Medicare billing volume and revenue compare to other providers nationally and within its state, across 22 CPT/HCPCS codes.

View: State1 / 2

Claims Volume vs. Indiana Distribution

Warren Chang — 2 of 22 codes billed far more than typical (above p95)

p5–p95 (all providers)p25–p75MedianThis providerOutlier

Rank Distribution — Indiana

Full comparison — all codes billed, vs. state median

22 rows

CPT/HCPCS Code	Rank	Provider Count	Median Claims	Avg Paid	Average Revenue
J0178	19	60	830	$690	$868.8K
66984	31	450	50	$480	$87.5K
67028	36	80	550	$80	$78.6K
J0585	44	80	8,460	$1	$51K
67904	14	20	50	$560	$37.8K
66982	95	120	30	$600	$29.4K
66821	32	240	60	$200	$23.1K
99214	1,904	10,540	110	$80	$15.5K
99213	481	10,820	80	$50	$7.6K
92136	15	160	190	$20	$7.1K

Showing 1–10 of 22

Related Providers

Other providers that share a Tax Identification Number (TIN) with Warren Chang, ranked by combined Medicare and Medicaid revenue.

Provider	State	Taxonomy	Medicare Revenue	Medicaid Revenue
Frank Hrisomalos	IN	Retina Specialist (Ophthalmology) Physician	$2.2M	$0
Integ Health System, P.C.	IN	Ambulatory Surgical Clinic/Center	$1.8M	$403.1K
Joseph Mackey	IN	Ophthalmology Physician	$2M	$0
Andrew Huck	IN	Ophthalmology Physician	$940.5K	$0

Nearby Providers

Other providers in the same ZIP code as Warren Chang, ranked by combined Medicare and Medicaid revenue.

Provider	State	Taxonomy	Medicare Revenue	Medicaid Revenue
Centerstone Of Indiana, Inc.	IN	Mental Health Clinic/Center (Including Community Mental Health Center)	$0	$318.8M
Southern Indiana Pediatrics, LLC	IN	Pediatrics Physician	$0	$10.7M
Limestone Health, LLC	IN	Methadone Clinic	$116.1K	$9M
Prime Healthcare Services - Monroe LLC	IN	General Acute Care Hospital	$0	$5.7M
Hands At Home, LLC	IN	Home Health Agency	$0	$4.1M
Bloomington Pediatric Dentistry L.L.C.	IN	Pediatric Dentistry	$0	$3.1M
Southern Indiana Surgery Center, LLC	IN	Ambulatory Surgical Clinic/Center	$1.4M	$516.1K
Bloomington Advanced Surgery Center, LLC	IN	Ambulatory Surgical Clinic/Center	$1.1M	$0
Bloomington Asc, LLC	IN	Ambulatory Surgical Clinic/Center	$706.5K	$0
Bloomington Endoscopy Center, LLC	IN	Ambulatory Surgical Clinic/Center	$663.6K	$0

Warren Chang — Billing Profile & Reimbursement Data

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Key Findings

Medicare: Total Revenue Breakdown by CPT/HCPCS Code

Medicare: Complete Services Breakdown

Medicare: Competitive Analysis & Benchmarks

Related Providers

Nearby Providers

Frequently Asked Questions

References