Medical emergency?Emergency? Call 911. Nearest emergency roomsNearest ERs

Internal Medicine

Christina L. Wei, MD

Works at hospitals in W Concord, MA · Lowell, MA · Massachusetts

Summary

Dr. Christina L. Wei, MD is an internal medicine doctor at 228 Billerica Rd, Chelmsford, MA 01824. Phone: (978) 250-6000. Accepts Medicare assignment. In 2024, Christina L. Wei had 179 Original Medicare patients and 1,647 services. NPI 1639167257. 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.

  • Specialty: Internal medicine doctor (Medicare lists Internal Medicine)
  • Address: 228 Billerica Rd, Chelmsford, MA 01824 · Directions
  • Phone: (978) 250‑6000
  • Medicare: Accepts Medicare assignment
  • Hospitals: Emerson Hospital -, Lowell General Hospital
  • Group practice: Atrius Health Inc
  • Medical school: University Of Massachusetts Medical School · graduated 1985 (41 years since medical school)
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Christina L. Wei, 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 Christina L. Wei accept Medicare assignment?
Yes. Medicare's clinician data says Christina L. Wei 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 Christina L. Wei see?
In 2024, CMS data shows 179 Original Medicare patients and 1,647 services for Christina L. Wei. This counts Original Medicare only and measures volume, not quality.
What is Christina L. Wei's NPI number?
1639167257. 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 Christina L. Wei, 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 patients179
Services billed to Medicare1,647
Different services or procedures99
Participating Medicare providerYes
Average age of these patients74

Most frequent services

  1. Insertion of needle into vein for collection of blood sample (36415)258 services
  2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)159 services
  3. Hemoglobin a1c level (83036)109 services
  4. Blood test, lipids (cholesterol and triglycerides) (80061)107 services
  5. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)68 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%
  • High blood pressure66%
  • Arthritis38%
  • Chronic kidney disease32%
  • Diabetes30%
  • Ischemic heart disease22%

Hospitals where Christina L. Wei works

Medicare's Facility Affiliation Data lists Christina L. Wei 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.

  • Emerson Hospital -W Concord, MA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 220084
  • Lowell General HospitalLowell, MA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 220063

Practice locations

Addresses where Christina L. Wei is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Christina L. Wei as a member of this group (CMS data updated October 2, 2026).

  • Atrius Health Inc1,222 clinicians in the group

Specialties

Find other Internal Medicine doctors in Massachusetts →

Other internal medicine doctors in Chelmsford

Clinicians with the same Medicare primary specialty in Chelmsford, MA — not a recommendation.

All internal medicine doctors in Chelmsford →

Other clinicians in Atrius Health Inc

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

Clinician information

CredentialMD
Medical schoolUniversity Of Massachusetts Medical School
Graduation year1985 (41 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1639167257
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