Dr. William Bryan Rivera , MD
Surgery • Apple Valley, CA
18144 Us Hwy 18 Suite 130
Apple Valley, CA 92307
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
-
NPI assigned on January 21, 2009; this date does not establish years in practice.
-
Published CMS data list 1,000 Original Medicare Part B services in 2024.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Published rows only; this is not a quality measure.
-
Published Part B service records, 2024:
- 99232 — Subsequent hospital care with moderate levelof medical decision making: 631 service units.
- 99223 — Initial hospital care with moderate level of medical decision making: 134 service units.
- 99204 — New patient outpatient office visit: 79 service units.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Units differ by code; these are not visits or a measure of quality.
CPT® only copyright 2023 American Medical Association. All rights reserved. Service names are shortened from CPT Consumer Friendly Descriptors (CMS data, 2024). CPT notice
See all 6 records in the table · Guide: How to read Medicare Part B data
-
Published CMS data list 178 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Published rows only; this is not a quality measure.
-
Published Part D records, 2024:
- Hydrocodone-Acetaminophen (Hydrocodone/Acetaminophen) — 74 prescription fills, including refills.
- Naloxone Hcl — 58 prescription fills, including refills.
- Acetaminophen-Codeine (Acetaminophen With Codeine) — 33 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See all 4 records in the table · Guide: How to read Medicare Part D prescriber data
-
More Medicare Part B services than 90% of clinicians listed under Surgery in California (2024, 1,346 clinicians with data). Median for this group: 213. Middle half: 101 to 404.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024. Billing and prescribing volume is not a quality rating.
-
Medicare Part B services went from 737 in 2020 to 1,000 in 2024.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2020–2024.
Practice Location & Contact Primary Location
18144 Us Hwy 18 Suite 130
Apple Valley, CA 92307
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
Medicare Profile & Education
Source: CMS Doctors and Clinicians National Downloadable File
New York Medical College
2003
What Public CMS Data Show
Surgery: NPPES taxonomy is a reported classification, not proof of board certification.
Medicare patients
249 people with Original Medicare in 2024
It gives a sense of how many people with Medicare this clinician treated that year.
Source: CMS, Medicare Physician & Other Practitioners – by Provider, 2024.
Medicare-allowed amount
About $102,083 in 2024
The total amount Medicare approved for these services in 2024. It includes what Medicare paid and what patients or their other insurance owed, such as the deductible and coinsurance.
It shows the total cost of this clinician's Original Medicare services under Medicare's fee rules.
What this does not show: Medicare-allowed amount
This is not the clinician's income. Part of it can go to a clinic or group practice, staff, equipment or drugs. It is not the price you will pay.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024.
Paid by Medicare
About $77,274 in 2024
The part of the Medicare-allowed amount that Medicare itself paid in 2024, after patients' deductibles and coinsurance.
The gap between the allowed amount and this number is roughly what patients and their other insurance paid.
What this does not show: Paid by Medicare
This is not the clinician's income and not a measure of quality.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2024.
30-day fills
178 standardized 30-day fills in 2024
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$3,935 in 2024
The total cost of these prescriptions in 2024, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024.
Open Payments general payments, program year 2025
All general payments: $238.80 across 2 records.
By nature of payment
- Food and Beverage: $238.80 across 2 records.
Reporting-company totals
- Madrigal Pharmaceuticals: $146.83 across 1 record.
- Elucent Medical: $91.97 across 1 record.
A reported payment does not necessarily mean the financial relationship is improper and is not a measure of care quality. Clinicians can review and dispute these records.
Source: Calculated by T-MedInfo from CMS Open Payments general-payment records for program year 2025 (published June 30, 2026).
Years since graduation
23 years (graduated 2003)
CMS Doctors and Clinicians data list 2003 as the year this clinician finished professional school.
It tells you roughly how long ago the clinician finished school.
What this does not show: Years since graduation
It is not the number of years in practice, and more years does not mean better care.
Source: CMS Doctors and Clinicians National Downloadable File.
NPI first issued
2009
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Accepts Medicare assignment
CMS data list this clinician as accepting Medicare assignment. This means agreeing to take the Medicare-approved amount as full payment for covered services.
With Original Medicare, you usually pay only your deductible and coinsurance, and the office sends the claim to Medicare for you.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, “Does your provider accept Medicare as full payment?”
No telehealth indicator
CMS shows this indicator only when recent Medicare claims include telehealth services. The clinician may still offer telehealth; ask the office.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Enrolled in Medicare (PECOS)
Dr. Rivera has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists Dr. Rivera as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Apple Valley and California
Billing and prescribing volume is not a quality rating.
Medicare Part B services
More Medicare Part B services than 90% of clinicians listed under Surgery in California (2024, 1,346 clinicians with data). Median for this group: 213. Middle half: 101 to 404.
Too few clinicians listed under Surgery in Apple Valley have Medicare Part B data for 2024 to compare.
Medicare-allowed amount
A higher Medicare-allowed amount than 85% of clinicians listed under Surgery in California (2024, 1,346 clinicians with data). Median for this group: $32,453. Middle half: $13,159 to $66,109.
Too few clinicians listed under Surgery in Apple Valley have Medicare Part B data for 2024 to compare.
Paid by Medicare
A higher Medicare payment amount than 85% of clinicians listed under Surgery in California (2024, 1,346 clinicians with data). Median for this group: $24,935. Middle half: $10,148 to $50,637.
Too few clinicians listed under Surgery in Apple Valley have Medicare Part B data for 2024 to compare.
Medicare Part D prescriptions
More Part D prescriptions than 85% of clinicians listed under Surgery in California (2024, 1,327 clinicians with data). Median for this group: 54. Middle half: 26 to 105.
Too few clinicians listed under Surgery in Apple Valley have Medicare Part D data for 2024 to compare.
Part D drug cost
A higher Part D drug cost than 85% of clinicians listed under Surgery in California (2024, 1,327 clinicians with data). Median for this group: $346. Middle half: $126 to $1,126.
Too few clinicians listed under Surgery in Apple Valley have Medicare Part D data for 2024 to compare.
13 active clinicians are listed under Surgery with a practice address in Apple Valley, CA (3,120 in California).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Apple Valley
7.7% of these 13 clinicians have the CMS telehealth indicator.
76.9% of these 13 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
-
Medicare Part B services
Medicare Part B services increased 36% from 737 in 2020 to 1,000 in 2024.
- 2020: 737
- 2021: 944
- 2022: 809
- 2023: 833
- 2024: 1,000
-
Medicare-allowed amount
Medicare-allowed amount stayed about the same: $107,153 in 2020 and $102,083 in 2024.
- 2020: $107,153
- 2021: $115,950
- 2022: $101,041
- 2023: $100,034
- 2024: $102,083
-
Paid by Medicare
Paid by Medicare stayed about the same: $84,352 in 2020 and $77,274 in 2024.
- 2020: $84,352
- 2021: $91,802
- 2022: $78,195
- 2023: $78,277
- 2024: $77,274
-
Medicare Part D prescriptions
Medicare Part D prescriptions increased 14% from 156 in 2020 to 178 in 2024.
- 2020: 156
- 2021: 214
- 2022: 209
- 2023: 234
- 2024: 178
-
30-day fills
30-day fills increased 13% from 158 in 2020 to 178 in 2024.
- 2020: 158
- 2021: 215
- 2022: 209
- 2023: 234
- 2024: 178
-
Part D drug cost
Part D drug cost decreased 52% from $8,115 in 2020 to $3,935 in 2024.
- 2020: $8,115
- 2021: $11,018
- 2022: $7,435
- 2023: $8,541
- 2024: $3,935
-
Industry payments (Open Payments)
Industry payments (Open Payments) went from $19.10 in 2019 to $238.80 in 2025.
- 2019: $19.10
- 2020: $97.74
- 2021: $67.88
- 2022: $18.09
- 2025: $238.80
Sources: CMS Medicare Physician & Other Practitioners (2024), CMS Medicare Part D Prescribers (2024), CMS Open Payments (2025), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo · Report an error.
Pharma & Medical Device Financial Disclosures
Payments and other transfers of value that drug and medical device companies reported to CMS Open Payments
Program year 2025 (payments made January 1 – December 31, 2025): fewer than 11 records totaling $238.80.
| Manufacturer | Payment Nature | Product | Type | Amount ($) |
|---|---|---|---|---|
| Madrigal Pharmaceuticals |
Food and Beverage
In-kind items and services
|
REZDIFFRA | General | $146.83 |
| Elucent Medical |
Food and Beverage
Cash or cash equivalent
|
— | General | $91.97 |
Source: CMS Open Payments, program year 2025, released June 30, 2026.
Performed Procedures & Service Volume
CPT® is a registered trademark of the American Medical Association. CPT codes, descriptions and other data only are copyright 2016–2023 American Medical Association. All rights reserved. Applicable FARS/HHSARS apply. Descriptions of CPT codes are the AMA's CPT Consumer Friendly Descriptors as published by CMS in the Medicare Physician & Other Practitioners – by Provider and Service data, 2017–2024; they are plain-language summaries, not for clinical coding or documentation. HCPCS Level II codes and descriptions are from CMS. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.
| HCPCS Code | Services | Patients | Submitted Charge | Medicare Allowed |
|---|---|---|---|---|
|
99232
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes
|
631 | 103 | $157.74 | $72.56 |
|
99223
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes
|
134 | 114 | $346.38 | $159.52 |
|
99204
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more
|
79 | 79 | $342.79 | $160.92 |
|
99291
Critical care, first 30-74 minutes
|
69 | 19 | $556.71 | $195.50 |
|
99213
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more
|
55 | 43 | $187.46 | $86.63 |
|
99214
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more
|
32 | 30 | $264.07 | $123.59 |
Source: CMS Part B by Provider and Service, 2024; services under 11 beneficiaries omitted by CMS. Privacy limits
Submitted charges are billed amounts, not a price quote for your visit.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Hydrocodone-Acetaminophen | Hydrocodone/Acetaminophen | 74 | 538 | $629.73 | 72 |
| Naloxone Hcl | Naloxone Hcl | 58 | 823 | $3,016.26 | 58 |
| Acetaminophen-Codeine | Acetaminophen With Codeine | 33 | 137 | $156.08 | 30 |
| Amoxicillin-Clavulanate Potass | Amoxicillin/Potassium Clav | 13 | 147 | $133.38 | 12 |
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
Self-certified to NPPES: 2024-03-22NUCC Taxonomy Code: 208600000X
A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of surgical conditions in the following areas: alimentary tract; abdomen; breast, skin and soft tissue; endocrine system; head and neck surgery; pediatric surgery; surgical critical care; surgical oncology; trauma and burns; and vascular surgery. General surgeons increasingly provide care through the use of minimally invasive and endoscopic techniques. Many general surgeons also possess expertise in transplantation surgery, plastic surgery and cardiothoracic surgery.
NUCC Taxonomy Code: 282N00000X
An acute general hospital is an institution whose primary function is to provide inpatient diagnostic and therapeutic services for a variety of medical conditions, both surgical and non-surgical, to a wide population group. The hospital treats patients in an acute phase of illness or injury, characterized by a single episode or a fairly short duration, from which the patient returns to his or her normal or previous level of activity.
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - COLORECTAL SURGERY (PROCTOLOGY)
I20100915000192
CA
8820113855
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
Career & Practice History Timeline
Changes recorded in monthly NPPES data files: addresses, names, credentials, specialties and NPI status
Registered at 18144 US HWY 18 SUITE 130, APPLE VALLEY, CA 92307 (Tel: 7602789477)
Registered at 12277 APPLE VALLEY RD #450, APPLE VALLEY, CA 92308 (Tel: 7602789477)
Recorded as WILLIAM RIVERA, M.D
General Acute Care Hospital
NPI status registered as active in NPPES database
Registered at 19341 BEAR VALLEY RD, SUITE 105 SAINT MARY SPECIALTY CLINIC, APPLE VALLEY, CA 923085151 (Tel: 7602476444)
Registered at 19341 BEAR VALLEY RD, SUITE 105 SAINT MARY SPECIALTY CLINIC, APPLE VALLEY, CA 923085151 (Tel: 7602476444)
Recorded as WILLIAM RIVERA, MD
Surgery (license number reported to NPPES: CA A 111003)
First registered as active Individual Practitioner in NPPES Database.
NPI Administrative Meta
Other Surgery Specialists in Apple Valley
- Dr. Nathan Chung, MD
- Peter Fischl, MAL
- Dr. James Hartleroad, MD
- Dr. Brian Patterson, MD, MPH
- Dr. Chris Okwuosa, MD
- Dr. Tracy Taggart, MD
Mailing Address
12277 Apple Valley Rd #450
Apple Valley, CA 92308
Phone: 7602789477