Dr. Mark Janzen, MD
What this data tells you about Dr. Janzen
Dr. Mark Janzen is a surgery specialist in Riverside, CA, with 18 years of NPI registration. Based on federal Medicare data, Dr. Janzen performed 691 Medicare services across 560 unique beneficiaries.
Between the years covered by Open Payments, Dr. Janzen received a total of $10,887 from 11 pharmaceutical and/or device companies across 42 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in surgery. The majority of payments are for speaking programs and promotional activities, reflecting participation in industry-sponsored events. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Janzen is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
Medicare Practice Summary
Medicare Utilization ↗Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
188 | $76 | $253 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
106 | $51 | $154 |
| Ultrasound guidance for blood vessel access Use of ultrasound imaging to help locate and access a blood vessel. This guidance assists healthcare providers in performing procedures such as inserting IV lines or drawing blood. |
59 | $11 | $92 |
| Sedation by physician, initial 15 minutes Administration of a drug to induce depression of consciousness by the physician performing a procedure. This code covers the initial 15 minutes of sedation for patients aged 5 years or older. |
42 | $10 | $28 |
| Initial hospital admission, moderate complexity Initial hospital inpatient or observation care for a new patient involving moderate-level medical decision making, with at least 55 minutes total time on the date of the encounter. |
39 | $102 | $274 |
| Radiologist review of arm or leg artery image A radiologist reviews images of the arteries in the arm or leg. This process involves analyzing the visual data to assess the blood vessels. |
36 | $64 | $180 |
| Initial hospital admission, high complexity Initial hospital inpatient or observation care for a new patient involving high-level medical decision making, with at least 75 minutes total time on the date of the encounter. |
33 | $134 | $377 |
| Hospital follow-up visit, low complexity Follow-up hospital visit for an established patient with straightforward or low-level medical decision making. The visit requires at least 25 minutes of time spent on the day of service. |
32 | $39 | $110 |
| Hospital follow-up visit, moderate complexity Follow-up hospital visit for an existing patient involving moderate medical decision making. The visit requires at least 35 minutes of time spent on the date of service. |
30 | $60 | $177 |
| Office visit, established patient (10-19 min) An office visit for an existing patient lasting 10 to 19 minutes. The visit involves medical evaluation and management of the patient's condition. |
28 | $28 | $80 |
| Hospital follow-up visit, high complexity Subsequent hospital inpatient or observation care for an existing patient involving high-level medical decision making, with at least 50 minutes total time on the date of the encounter. |
22 | $95 | $266 |
| Radiologist review of abdominal aorta image A radiologist reviews images of the abdominal aorta to evaluate the blood vessel. |
20 | $52 | $146 |
| Arterial thrombectomy, chest, neck, or brain A procedure to remove a blood clot and part of an artery in the chest, neck, or brain. |
17 | $571 | $1,739 |
| New patient office visit (30-44 min) An initial office visit for a new patient lasting between 30 and 44 minutes. This code is used when the total time spent on the date of the encounter falls within this range. |
13 | $55 | $184 |
| New patient office visit (45-59 min) An initial office visit for a new patient lasting between 45 and 59 minutes. This code covers the total time spent by the physician or qualified healthcare professional on the date of the encounter. |
13 | $90 | $297 |
| Office visit, established patient, complex (40-54 min) An office or outpatient visit for an existing patient lasting between 40 and 54 minutes. This level of service is determined by the total time spent on the date of the encounter. |
13 | $114 | $346 |
Industry Payment Transparency
Open Payments through 2024 ↗Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
Payments by company (2024)
All-time payments by company (2018-2024) ›
Associated products mentioned in payments ›
The majority of payments (76%) are for speaking programs and promotional activities, which reflect participation in industry-sponsored educational or marketing events. This is common in surgery and does not inherently indicate bias, but patients may wish to be aware.
Geographic Context
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Janzen is a clinical cardiology specialist, with above-average Medicare volume (top 13% in CA), with speaking/promotional industry engagement, with 18 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Janzen experienced with office visit, established patient (30-39 min)?
Does Dr. Janzen receive payments from pharmaceutical companies?
How do Dr. Janzen's costs compare to other surgerists in Riverside?
What does Data Coverage mean?
Is this data up to date?
Explore related providers
All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
Provider corrections: Provider portal · Privacy questions: Privacy Policy · Terms: Terms of Use · Methodology: Methodology