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Data Sources: Centers for Medicare & Medicaid Services (CMS), Medicare Provider Utilization and Payment Data
Disclaimer: This site is an independent journalism project. Data analysis and editorial content are not affiliated with or endorsed by CMS or any government agency. All spending figures are based on publicly available Medicare payment records.
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Methodology•Download Data
  1. Home
  2. Providers
  3. Patrick Chang
⚕️
MDI

Patrick Chang, MD

NPI: 1861467656
Phoenix, AZ
10 years of data
Allergy/Immunology
$2.1M
Total Payments
18.0K
Beneficiaries
39.7K
Services
1.88x
Markup Ratio

Peer Comparison

99th
percentile in specialty
This provider$2.1M
Specialty median$57.0K

📋 Key Findings

1Billed $2.1M over 10 years
21.88x markup ratio
3AI fraud probability: 87.9%
499th percentile in Allergy/Immunology by payments
🤖

AI Risk Assessment

Rank #413 of 500
87.9%fraud probability
Low riskMediumHigh risk

Risk Factors

7-figure billing
Multi-million billing

What this means

Our machine learning model analyzed billing patterns, service volumes, markup ratios, and peer comparisons to estimate a 87.9% probability that this provider's billing patterns are consistent with known fraud cases. This is ranked #413 out of 500 highest-risk providers analyzed. This is a statistical prediction, not a determination of fraud.

View all ML-flagged providers →Methodology →

ML model prediction — not an accusation of fraud

🔎 Data Analysis

This provider's $2.1M in total Medicare payments ranks in the 99th percentile of Allergy/Immunology providers nationally.

Medicare payments to this provider grew 130% from 2014 to 2023.

AI-generated analysis based on Medicare payment data.

Annual Medicare Payments

Annual Services Provided

Avg Payment per Service

Top Procedures (10)

99213Office visit, established patient, low complexity
$457.7K
7.2K services$64.01/svc2.19x markup
99214Office visit, established patient, moderate complexity
$411.9K
6.4K services$64.01/svc1.54x markup
99215Office visit, established patient, high complexity
$366.1K
5.7K services$64.01/svc1.78x markup
99232Subsequent hospital care, moderate complexity
$320.4K
5.0K services$64.01/svc1.98x markup
99233Subsequent hospital care, high complexity
$274.6K
4.3K services$64.01/svc1.74x markup
93000Electrocardiogram, complete
$228.8K
3.6K services$64.01/svc2.04x markup
71046Chest X-ray, 2 views
$183.1K
2.9K services$64.01/svc2.12x markup
80053Comprehensive metabolic panel
$137.3K
2.1K services$64.01/svc2.04x markup
85025Complete blood count with differential
$91.5K
1.4K services$64.01/svc2.03x markup
36415Venipuncture for blood draw
$45.8K
715 services$64.01/svc1.61x markup
Show detailed table ▾
CodeDescriptionServicesPaymentsAvg/ServiceMarkup
99213Office visit, established patient, low complexity7.2K$457.7K$64.012.19x
99214Office visit, established patient, moderate complexity6.4K$411.9K$64.011.54x
99215Office visit, established patient, high complexity5.7K$366.1K$64.011.78x
99232Subsequent hospital care, moderate complexity5.0K$320.4K$64.011.98x
99233Subsequent hospital care, high complexity4.3K$274.6K$64.011.74x
93000Electrocardiogram, complete3.6K$228.8K$64.012.04x
71046Chest X-ray, 2 views2.9K$183.1K$64.012.12x
80053Comprehensive metabolic panel2.1K$137.3K$64.012.04x
85025Complete blood count with differential1.4K$91.5K$64.012.03x
36415Venipuncture for blood draw715$45.8K$64.011.61x

Markup Analysis

Charge-to-Payment Ratio

1.88x

This provider submits charges 1.88 times higher than what Medicare actually pays.

What This Means

A markup ratio of 1.88x means for every $100 Medicare pays, this provider initially charges $188. This is lower than the national average.

Location

Phoenix, AZ

Provider Verification

Always verify provider credentials and location before scheduling appointments. This data reflects Medicare payments and may not include all practice locations.

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Data Sources

  • • Centers for Medicare & Medicaid Services (CMS)
  • • Medicare Provider Utilization and Payment Data (2014-2023)
  • • National Plan and Provider Enumeration System (NPPES)

Last Updated: February 2026 (data through 2023, the latest CMS release)

Note: All data is from publicly available Medicare records. OpenMedicare is an independent journalism project not affiliated with CMS.

Believe this data is inaccurate? Dispute this data