2026 NPPES data Hospitalist Physician NPI 1538393541 D.O.
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MARK GROHMAN, D.O.

Hospitalist Physician in BIDDEFORD, Maine. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
113
Medicare Part D claims · 46 beneficiaries · Hospitalist Physician avg: 888
What the federal data reveals: MARK GROHMAN, D.O. is a Hospitalist Physician ([object Object]) practicing in BIDDEFORD, Maine with a Medicare Part D prescribing footprint of 113 claims across 46 beneficiaries .

What stands out: MARK GROHMAN, D.O. filed 113 Medicare Part D claims in 2023 across BIDDEFORD, Maine. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

MARK GROHMAN, D.O. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

MARK GROHMAN, D.O. at a glance

Quality data not reported

NPI registry status

Active

Issued 05/05/2009

NPI 1538393541

Primary specialty

Hospitalist Physician

Mid-sized

16,825 US NPIs in this specialty

Medicare Part D claims

113 87% vs specialty avg

2023 prescription claims

Specialty avg: 888

Specialty distribution in Maine

How Hospitalist Physician compares to other specialties among Maine providers

Maine providers

Hospitalist Physician share within Maine

1. Hospitalist Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Hospitalist Physician share within Maine

Specialty board-certification context

Estimated specialty board-certified rate — Hospitalist Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Hospitalist Physician ABMS/AOA estimate

Est. board-certified rate (Hospitalist Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Hospitalist Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

MARK GROHMAN, D.O. is a Hospitalist Physician provider practicing in BIDDEFORD, Maine, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: D.O.. NPI: 1538393541. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

MARK GROHMAN, D.O. appears in the CMS NPPES registry as a Hospitalist Physician provider holding D.O. credentials at ONE MEDICAL CENTER DRIVE, BIDDEFORD, ME, 04005, with a listed phone of (207) 283-7000. NPI 1538393541 was issued on 05/05/2009. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GROHMAN most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 113 prescription claims written by this provider, covering 46 Medicare beneficiaries and totaling roughly $7K in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Hospitalist Physician is a mid-sized specialty nationwide, with 16,825 enrolled providers across 54 states and an average of 888 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

ONE MEDICAL CENTER DRIVE
BIDDEFORD, ME 04005

Provider Details

NPI 1538393541
Specialty Hospitalist Physician
Credentials D.O.
Gender Male
NPI Issued 05/05/2009

Hospital and facility affiliations

Facilities where MARK GROHMAN, D.O. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

MERCY HOSPITAL
PORTLAND, ME

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

113
Total Claims
$7K
Total Drug Cost
46
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
123
Total Day Supply
2,316
Generic Drug Cost
$881
Antibiotic Claims
25

Patient Demographics

Average Patient Age
70.0 years
Avg HCC Risk Score
2.57
Gender Split
57% female / 43% male
Age Distribution
<65: 13, 65-74: 15, 75-84: N/A, 85+: N/A

Hospitalist Physician Overview

How MARK GROHMAN, D.O. fits within the Hospitalist Physician landscape nationally.

16,825
Hospitalist Physician Providers in US
54
States with Hospitalist Physician
888
Avg Claims per Provider

MARK GROHMAN, D.O.'s 113 claims are below the specialty average of 888.

Nearby Hospitalist Physician Providers in Maine

Other clinicians with the same primary specialty enrolled in Maine, drawn from the same CMS NPPES roster as GROHMAN.

Compare Hospitalist Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is MARK GROHMAN, D.O.'s specialty?
MARK GROHMAN, D.O. specializes in Hospitalist Physician and practices in BIDDEFORD, Maine. Credentials: D.O..
How much does MARK GROHMAN, D.O. prescribe under Medicare Part D?
In 2023, MARK GROHMAN, D.O. wrote 113 Medicare Part D claims totaling $7K in drug costs for 46 beneficiaries.
Where is MARK GROHMAN, D.O. located?
MARK GROHMAN, D.O. is located at ONE MEDICAL CENTER DRIVE, BIDDEFORD, ME, 04005. Phone: (207) 283-7000.
What is MARK GROHMAN, D.O.'s NPI number?
MARK GROHMAN, D.O.'s National Provider Identifier (NPI) is 1538393541, issued on 05/05/2009.
How many Hospitalist Physician providers are there in the US?
There are 16,825 Hospitalist Physician providers across 54 states in the US. The average Hospitalist Physician provider writes 888 Medicare Part D claims per year.
Does MARK GROHMAN, D.O. accept Medicare?
MARK GROHMAN, D.O. appears in CMS Medicare data with 113 Part D claims and 46 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARK GROHMAN, D.O.'s credentials?
MARK GROHMAN, D.O.'s NPI is 1538393541 with credentials D.O.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology