Quick answers
- Does Mariaelena O. Williams accept Medicare assignment?
- Yes. Medicare's clinician data says Mariaelena O. Williams accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Mariaelena O. Williams see?
- In 2024, CMS data shows 98 Original Medicare patients and 242 services for Mariaelena O. Williams. This counts Original Medicare only and measures volume, not quality.
- What is Mariaelena O. Williams's NPI number?
- 1710415237. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Mariaelena O. Williams, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 98 |
|---|---|
| Services billed to Medicare | 242 |
| Different services or procedures | 31 |
| Participating Medicare provider | Yes |
| Average age of these patients | 71 |
Most frequent services
- Injection, propofol, 10 mg (J2704)87 services
- Injection of anesthetic agent and/or steroid into thigh nerve (femoral nerve) (64447)25 services
- Anesthesia for procedure for total knee joint replacement (01402)22 services
- Anesthesia for exam of uterus using an endoscope (00952)17 services
- Infusion, normal saline solution , 1000 cc (J7030)11 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol75%
- Arthritis75%
- High blood pressure65%
- Depression22%
- Anxiety21%
- Diabetes20%
Practice locations
Addresses where Mariaelena O. Williams is enrolled with Medicare (CMS data updated October 2, 2026).
- 4605 E Elwood St, Suite 500Phoenix, AZ 85040 (602) 200‑9021
Group practices
Medicare enrollment lists Mariaelena O. Williams as a member of this group (CMS data updated October 2, 2026).
- Anesthesia Partners of Arizona LLC84 clinicians in the group
Specialties
- Anesthesiologyprimary
Other anesthesiologists in Phoenix
Clinicians with the same Medicare primary specialty in Phoenix, AZ — not a recommendation.
Other clinicians in Anesthesia Partners of Arizona LLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Colorado School Of Medicine, Aurora |
| Graduation year | 2017 (9 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1710415237 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians