Doctor profile · Federal record

Dr. Mary Ellen O'Brien, M.D.

Internal Medicine Physician (CMS: Hospitalist) · Providence, RI

  • NPI 1144425000
  • Accepts Medicare
  • MIPS 79.9 / 100 · 2023
  • 19 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
593 Eddy St
Providence, RI 029034923
(401) 444-4083
fax (401) 444-3056

Credentials & registration

NPPES · NUCC
NPI registered
June 2007 — 19 yrs on file
Profile last updated
January 22, 2010
Year of graduation
2007 — 19 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
Rhode Island #LP01243

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1144425000. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
623
Distinct HCPCS
5
Medicare allowed
$107,533
HCPCS Description Services Patients Avg allowed
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 466 454 $184
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 96 96 $137
99221 Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes 33 33 $88
99291 Critical care, first 30-74 minutes 15 15 $225
99235 Initial hospital care with same-day admission and discharge with moderate level of medical decision making, per day, if using time, at least 70 minutes 13 13 $169

In context: peer comparison

Among 103 peers in Providence Internal Medicine Physician, average services per provider: 76. This provider delivers 8.2× the peer median.

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Mary Ellen O'Brien's medical specialty?
Dr. Mary Ellen O'Brien practices Internal Medicine Physician in Providence, RI.
Where does Dr. Mary Ellen O'Brien practice?
Dr. Mary Ellen O'Brien practices at 593 Eddy St, Providence, RI 029034923. Office phone: 4014444083.
What is Dr. Mary Ellen O'Brien's NPI?
Dr. Mary Ellen O'Brien's National Provider Identifier (NPI) is 1144425000, issued by NPPES.
Does Dr. Mary Ellen O'Brien accept Medicare assignment?
Yes. Dr. Mary Ellen O'Brien accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mary Ellen O'Brien commonly perform?
Top Medicare-reported procedures in 2023: Initial hospital care with moderate level of medical decision making (HCPCS 99223); Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222); Initial hospital care with straightforward or low level of medical decision making (HCPCS 99221). Source: CMS Medicare Physician & Other Practitioners file.