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Physician Assistant

Sierra R. Robertson, PA

Works at hospitals in Dayton, WA · Walla Walla, WA · Washington

Summary

Sierra R. Robertson, PA is a physician assistant at 380 Chase Ave, Walla Walla, WA 99362. Phone: (509) 897-3333. Accepts Medicare assignment. In 2024, Sierra R. Robertson had 208 Original Medicare patients and 389 services. NPI 1457937724. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Sierra R. Robertson, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Sierra R. Robertson accept Medicare assignment?
Yes. Medicare's clinician data says Sierra R. Robertson 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 Sierra R. Robertson see?
In 2024, CMS data shows 208 Original Medicare patients and 389 services for Sierra R. Robertson. This counts Original Medicare only and measures volume, not quality.
What is Sierra R. Robertson's NPI number?
1457937724. 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 Sierra R. Robertson, 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 patients208
Services billed to Medicare389
Different services or procedures16
Participating Medicare providerYes
Average age of these patients78

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)232 services
  2. Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)46 services
  3. Programming of dual lead pacemaker system (93280)20 services
  4. Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)13 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 blood pressure75%
  • High cholesterol75%
  • Ischemic heart disease54%
  • Arthritis51%
  • Atrial fibrillation49%
  • Heart failure38%

Hospitals where Sierra R. Robertson works

Medicare's Facility Affiliation Data lists Sierra R. Robertson at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Sierra R. Robertson is enrolled with Medicare (CMS data updated October 2, 2026).

  • 380 Chase AveWalla Walla, WA 99362 (509) 897‑3333
  • 401 W Poplar StWalla Walla, WA 99362

Group practices

Medicare enrollment lists Sierra R. Robertson as a member of this group (CMS data updated October 2, 2026).

  • Providence Health and Services - Washington270 clinicians in the group

Specialties

Find other clinicians: Physician Assistant, Washington →

Other physician assistants in Walla Walla

Clinicians with the same Medicare primary specialty in Walla Walla, WA — not a recommendation.

All physician assistants in Walla Walla →

Other clinicians in Providence Health and Services - Washington

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialPA
Graduation year2020
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1457937724
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians