DR. WARREN LEWIS FIELDS M.D.
NPI 1821083999
Internal Medicine in Mystic, CT

Q: What is Warren Fields's NPI number?

The NPI number for Warren Fields is 1821083999. It was assigned to this individual provider in the NPPES registry on September 15, 2005.

Q: What is Warren Fields's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Warren Fields was last updated on December 22, 2009. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since September 15, 2005PECOS EnrolledAccepts Medicare Assignment

93.56/100

CMS Quality Rating

200 SANDY HOLLOW RD, MYSTIC, CT 06355(860) 572-8911(860) 572-7758 Get Directions Write a Review

NPPES record last updated: December 22, 2009. Verified against the NPPES registry weekly; last sync: October 25, 2026.

On this page

About Dr. Warren Lewis Fields M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. WARREN LEWIS FIELDS M.D. (NPI 1821083999) is an individual internal medicine provider in Mystic, Connecticut, licensed in Connecticut (035098) and active in the NPI registry since September 2005. He is enrolled in Medicare PECOS, is affiliated with Westerly Hospital, and is a graduate of University Of Connecticut School Of Medicine (1991).

NPPES Registry Identity

NPI1821083999

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameDR. WARREN LEWIS FIELDSCredential: M.D.

Location Address200 SANDY HOLLOW RDMystic, CT 06355-1720

Mailing Address200 Sandy Hollow RdMystic, CT 06355-1720 · (860) 572-8911 · Fax (860) 572-7758

Phone(860) 572-8911

Fax(860) 572-7758

Sole ProprietorNo

Medical School CMSUniversity Of Connecticut School Of MedicineGraduated 1991

Enumeration DateSeptember 15, 2005

Last NPPES UpdateDecember 22, 2009

✔ NPI 1821083999 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in CT · 035098

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

200 SANDY HOLLOW RD, Mystic, CT 06355

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Other Identifiers 2

Medicare UPIN110006231CT

Medicare UPING38241CT

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Warren Lewis Fields M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID6608916788

PECOS Enrollment IDI20091222000080

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show Warren Fields reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Hartford Healthcare Medical Group, Inc

41 mi

Surgery

1290 SILAS DEANE HWY, ATTN: LINDA STRAKA
Wethersfield, CT 06109

Reassigned Medicare billing, Connecticut enrollment
747 clinicians in this Medicare group

NPI 1043561301 (860) 972-9033

Ipc Hospitalists Of New England, P.C.

61 mi

Internal Medicine

819 WORCESTER ST, SUITE 3
Springfield, MA 01151

Reassigned Medicare billing, Connecticut enrollment
Medicare enrollment name: Ipc Hospitalists Of New England PC
88 clinicians in this Medicare group

NPI 1659555266 (413) 543-6820

Hospital Medicine Associates LLC

1,301 mi

Hospitalist

17000 MEDICAL CENTER DR
Baton Rouge, LA 70816

Reassigned Medicare billing, Connecticut enrollment
127 clinicians in this Medicare group

NPI 1093758781 (225) 752-2470

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 15

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

688 services291 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

386 services205 patients

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

203 services136 patients

Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit G0439

An annual wellness visit is a yearly appointment with your primary care provider to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's a subsequent visit, meaning it follows an initial assessment.

133 services133 patients

Hemoglobin a1c level 83036

Hemoglobin A1c (HbA1c) is a test that measures your average blood sugar level over the past 2-3 months. It's used to monitor how well diabetes is being controlled. High levels may indicate that your diabetes treatment plan needs adjustment.

89 services57 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

84 services83 patients

Administration of influenza virus vaccine G0008

The administration of the influenza virus vaccine, also known as the flu shot, is a simple procedure to protect against the flu. A healthcare provider injects a small dose of the vaccine into your arm. This stimulates your immune system to produce antibodies, which will help your body fight off the flu if exposed.

80 services80 patients

Influenza vaccine split virus, preservative free 90662

The Influenza Vaccine Split Virus, preservative-free, is a flu shot to protect against the influenza virus. It is made from parts of inactivated flu viruses and doesn't contain preservatives, reducing potential side effects. It helps your body develop immunity to the flu.

68 services68 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233

Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.

37 services28 patients

Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000

An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.

29 services28 patients

Transitional care management services for problem of at least moderate complexity 99495

Transitional care management services focus on coordinating and managing your care after you leave the hospital. For moderate complexity problems, this involves managing your medications, arranging further treatments, and ensuring you have the necessary follow-ups.

22 services21 patients

Urinalysis, manual test 81002

A urinalysis is a simple, non-invasive test that checks the urine for various elements such as sugar, protein, and signs of infection. It can help detect many common conditions, including kidney disease and diabetes. The manual test involves a lab technician examining a urine sample.

20 services18 patients

Physician or allowed practitioner re-certification for medicare-covered home health services under a home health plan of care (patient not present), including contacts with home health agency and review of reports of patient status required by physicians a G0179

This procedure involves a doctor or approved practitioner reviewing your health status and re-certifying your need for Medicare-covered home health services. It includes communication with the home health agency and assessment of your health reports, even when you're not physically present.

18 services14 patients

Pneumococcal conjugate vaccine, 20 valent (pcv20), for intramuscular use 90677

The Pneumococcal Conjugate Vaccine (PCV20) is a shot given to protect against 20 types of bacteria that can cause serious infections like pneumonia and meningitis. It's administered through a muscle, usually in the arm. It's important for overall health.

14 services14 patients

Administration of pneumococcal vaccine G0009

The pneumococcal vaccine helps protect against pneumococcal bacteria, which can cause severe infections like pneumonia and meningitis. The vaccine is given as an injection, typically in the arm. It's recommended for infants, older adults, and those with certain health conditions.

14 services14 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Westerly Hospital

Acute Care Hospitals · Westerly, RI

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number410013

Location25 Wells StreetWesterly, RI 02891 · Washington County

Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 06355 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$138.84 typical visit price

range $60.82 – $183.10

Typical copayment $34.71 (range $15.20 – $45.77)

Most-billed visit code 99204

Established Patient

$106.68 typical visit price

range $19.76 – $149.26

Typical copayment $26.67 (range $4.94 – $37.31)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

93.56/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored through an Alternative Payment Model

Quality

78.51

Promoting Interoperability

100

Improvement Activities

Reported Quality Measures

Care Plan

Percentage of patients aged 65 years and older who have an advance care plan or surrogate decision maker documented in the medical record that an advance care plan was discussed but the patient did not wish or was not able to name a surrogate decision maker…

99%317 patients4/55-star benchmark: 100%

Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

Referred Medical Equipment & Supplies CMS DME claims 8

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253

DME-Other DME · category DE017N

9 suppliers12 claims36 services$4.85 avg. paid by Medicare

Portable gaseous oxygen system, rental; includes portable container, regulator, flowmeter, humidifier, cannula or mask, and tubing E0431

DME-Oxygen and Supplies · category DC000N

2 suppliers28 claims28 services$16.34 avg. paid by Medicare

Wheelchair accessory, headrest, cushioned, any type, including fixed mounting hardware, each E0955

DME-Wheelchairs · category DD021N

1 supplier12 claims12 services$13.34 avg. paid by Medicare

Wheelchair accessory, manual swingaway, retractable or removable mounting hardware for joystick, other control interface or positioning accessory E1028

DME-Wheelchairs · category DD021N

1 supplier12 claims36 services$13.62 avg. paid by Medicare

Manual adult size wheelchair, includes tilt in space E1161

DME-Wheelchairs · category DD000N

1 supplier12 claims12 services$181.16 avg. paid by Medicare

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390

DME-Oxygen and Supplies · category DC002N

2 suppliers29 claims29 services$87.14 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 7

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. THOMAS MARCH BLUM M.D.

Internal Medicine