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Methodology•Download Data
  1. Home
  2. Providers
  3. Sean Wollaston
⚕️
MDIndividual

Sean Wollaston, M.D.

NPI: 1316921075
North Hollywood, CA
10 years of data
Rheumatology
$3.3M
Total Payments
43.7K
Beneficiaries
113.4K
Services
2.7x
Markup Ratio

Peer Comparison

95th
percentile in specialty
This provider$3.3M
Specialty median$352.6K

📋 Key Findings

1Billed $3.3M over 10 years
22.7x markup ratio (above median)
395th percentile in Rheumatology by payments
47 procedures with >3x markup
✓ No flags detected

🔎 Data Analysis

This provider's $3.3M in total Medicare payments ranks in the 95th percentile of Rheumatology providers nationally.

This provider's billing patterns fall within normal ranges for their specialty.

AI-generated analysis based on Medicare payment data.

Annual Medicare Payments

Annual Services Provided

Avg Payment per Service

Markup Ratio Over Time

Submitted Charges vs. Medicare Payments

Average per-service amounts submitted by the provider compared to what Medicare actually paid — the gap represents the markup.

YearAvg SubmittedAvg PaidMarkup RatioGap per ServiceTotal PaymentsServicesBeneficiaries
2014$87.24$35.432.46x$51.81$328.7K13.0K5.4K
2015$91.59$34.322.67x$57.27$295.1K11.8K4.3K
2016$94.35$36.242.60x$58.11$315.4K12.4K4.7K
2017$87.55$35.722.45x$51.83$330.8K13.5K5.3K
2018$97.64$34.392.84x$63.25$316.9K12.8K5.0K
2019$106.61$35.333.02x$71.28$368.3K15.7K6.3K
2020$103.31$32.143.21x$71.17$316.6K14.0K5.2K
2021$104.15$35.132.96x$69.02$309.9K7.8K3.5K
2022$151.38$54.302.79x$97.08$336.4K6.2K2.3K
2023$150.47$52.632.86x$97.84$370.0K6.2K1.9K

Top Procedures (20)

99214Established patient office or other outpatient, visit typically 25 minutes
$1.5M
16.1K services$94.52/svc2.27x markup
99215Established patient office or other outpatient, visit typically 40 minutes
$164.4K
1.3K services$122.57/svc2.16x markup
20611Aspiration and/or injection of major joint or joint capsule with recording and reporting using ultrasound guidance⚠ 3.5x markup
$131.6K
1.6K services$80.41/svc3.45x markup
96401Non-hormonal anti-neoplastic chemotherapy beneath the skin or into muscle
$109.1K
1.7K services$65.04/svc2.75x markup
99204New patient office or other outpatient visit, typically 45 minutes
$105.4K
801 services$131.58/svc2.51x markup
96372Injection beneath the skin or into muscle for therapy, diagnosis, or prevention⚠ 4.0x markup
$88.1K
5.3K services$16.53/svc3.95x markup
96413Infusion of chemotherapy into a vein up to 1 hour
$87.0K
714 services$121.85/svc2.74x markup
99205New patient office or other outpatient visit, typically 60 minutes
$75.7K
450 services$168.21/svc2.42x markup
82306Vitamin D-3 level
$67.2K
1.9K services$36.02/svc2.33x markup
86225Measurement of DNA antibody
$62.3K
3.8K services$16.34/svc2.39x markup
86160Measurement of complement (immune system proteins)
$59.5K
4.1K services$14.40/svc2.95x markup
80053Blood test, comprehensive group of blood chemicals⚠ 3.7x markup
$58.8K
6.0K services$9.79/svc3.72x markup
85025Complete blood cell count (red cells, white blood cell, platelets), automated test
$56.5K
6.0K services$9.45/svc2.87x markup
76942Ultrasonic guidance imaging supervision and interpretation for insertion of needle⚠ 4.1x markup
$49.4K
860 services$57.47/svc4.09x markup
96365Infusion into a vein for therapy, prevention, or diagnosis up to 1 hour⚠ 4.1x markup
$48.5K
757 services$64.08/svc4.08x markup
J0897Injection, denosumab, 1 mg
$46.1K
3.1K services$14.69/svc2.06x markup
83735Magnesium level
$39.5K
4.9K services$8.05/svc2.07x markup
86161Measurement of complement function (immune system proteins)⚠ 3.2x markup
$37.7K
2.4K services$15.73/svc3.18x markup
86140Measurement C-reactive protein for detection of infection or inflammation⚠ 8.7x markup
$33.9K
5.4K services$6.30/svc8.68x markup
99213Established patient office or other outpatient visit, typically 15 minutes
$33.6K
529 services$63.59/svc2.05x markup
Show detailed table ▾
CodeDescriptionServicesPaymentsAvg/ServiceMarkup
99214Established patient office or other outpatient, visit typically 25 minutes16.1K$1.5M$94.522.27x
99215Established patient office or other outpatient, visit typically 40 minutes1.3K$164.4K$122.572.16x
20611Aspiration and/or injection of major joint or joint capsule with recording and reporting using ultrasound guidance1.6K$131.6K$80.413.45x
96401Non-hormonal anti-neoplastic chemotherapy beneath the skin or into muscle1.7K$109.1K$65.042.75x
99204New patient office or other outpatient visit, typically 45 minutes801$105.4K$131.582.51x
96372Injection beneath the skin or into muscle for therapy, diagnosis, or prevention5.3K$88.1K$16.533.95x
96413Infusion of chemotherapy into a vein up to 1 hour714$87.0K$121.852.74x
99205New patient office or other outpatient visit, typically 60 minutes450$75.7K$168.212.42x
82306Vitamin D-3 level1.9K$67.2K$36.022.33x
86225Measurement of DNA antibody3.8K$62.3K$16.342.39x
86160Measurement of complement (immune system proteins)4.1K$59.5K$14.402.95x
80053Blood test, comprehensive group of blood chemicals6.0K$58.8K$9.793.72x
85025Complete blood cell count (red cells, white blood cell, platelets), automated test6.0K$56.5K$9.452.87x
76942Ultrasonic guidance imaging supervision and interpretation for insertion of needle860$49.4K$57.474.09x
96365Infusion into a vein for therapy, prevention, or diagnosis up to 1 hour757$48.5K$64.084.08x
J0897Injection, denosumab, 1 mg3.1K$46.1K$14.692.06x
83735Magnesium level4.9K$39.5K$8.052.07x
86161Measurement of complement function (immune system proteins)2.4K$37.7K$15.733.18x
86140Measurement C-reactive protein for detection of infection or inflammation5.4K$33.9K$6.308.68x
99213Established patient office or other outpatient visit, typically 15 minutes529$33.6K$63.592.05x

Markup Analysis

Charge-to-Payment Ratio

2.7x

This provider submits charges 2.7 times higher than what Medicare actually pays.

What This Means

A markup ratio of 2.7x means for every $100 Medicare pays, this provider initially charges $270. This is higher than the national average.

Location

North Hollywood, CA

Provider Verification

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

Similar Providers

Other Rheumatology providers in CA for peer comparison.

Sean Wollaston (you)
$3.3M
Barry Eibschutz, M.D.
$55.8M
Shariar Cohen-Gadol, M.D.⚠️
$49.5M
Gerald Ho, M.D.
$45.8M
Arash Horizon, M.D.
$45.0M
Daniel Watrous, M.D.
$41.6M
Show detailed table ▾
ProviderLocationTotal PaymentsStatus
Barry Eibschutz, M.D.San Luis Obispo, CA$55.8M✓ Clear
Shariar Cohen-Gadol, M.D.Thousand Oaks, CA$49.5M⚠️ Flagged
Gerald Ho, M.D.La Palma, CA$45.8M✓ Clear
Arash Horizon, M.D.Los Angeles, CA$45.0M✓ Clear
Daniel Watrous, M.D.Visalia, CA$41.6M✓ Clear

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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