Mark A Sierra, MD

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

• McLaren Bay Region Hospital · Bay City, MI
• McLaren Central Michigan Hospital · Mount Pleasant, MI
• Mymichigan Medical Center West Branch Hospital · West Branch, MI

Colleagues at McLaren Bay Region

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 111 clinicians in the practice; 12 are shown here.

• Miss. Bridget Marie Cashin, RN Gerontology Nurse Practitioner · Lansing, MI
• Melissa Duchene, FNP-BC Family Nurse Practitioner · West Branch, MI
• Everett Russell Kalcec, DO Family Medicine Physician · Midland, MI
• Ujwala Koduru, MD Internal Medicine Physician · Lansing, MI
• Dr. Paul Lazar, MD Family Medicine Physician · Flint, MI
• Jacob Kameron Leroux Family Medicine Physician · Bay City, MI
• Andrea Lieber, NP Family Nurse Practitioner · Bay City, MI
• Mrs. Madison Loruss, PA-C Physician Assistant · Bay City, MI
• Jennifer Schlitzkus Physician Assistant · Harrison, MI
• Marilyn Staines, DO Family Medicine Physician · Saginaw, MI
• Dr. Allison Leigh Wood, DOMPH Gastroenterology Physician · Lansing, MI
• Mr. Matthew Zamora, PA-C Internal Medicine Physician · Bay City, MI

Other providers in West Branch

• Aliya Frances Browne, DO

  Individual Cardiovascular Disease Physician · NPI 1154361400

  2431 S M 30, West Branch, MI 48661-9312 · (989) 343-3130