NPI registry status
Active
2026 NPPES data Gastroenterology Physician NPI 1336137306 M.D.
Verify on CMS → Robert Graveline, M.D.
Gastroenterology Physician in Ames, Iowa.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,601 in Gastroenterology Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
2K
Medicare Part D claims · 692 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
75%
generic claims · 25% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
Robert Graveline, M.D. filed 1,521 Medicare Part D claims in 2023 as a Gastroenterology Physician in Ames, Iowa, prescribing 75% generic.
- 2K
- Part D claims, 2023
- 75%
- generic prescribing
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Robert Graveline, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
1,521 Top 19% higher than 81% of 1,370,886 prescribers
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source CMS Medicare Part D Prescriber Public Use File · 2023
◑
Board-eligible specialty (heuristic, not verified)
Robert Graveline, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Robert Graveline, M.D.?
Quality data not reportedPrimary specialty
Gastroenterology Physician
Medicare Part D claims
1,521 83% vs specialty avg
Specialty distribution in Iowa
How Gastroenterology Physician compares to other specialties among Iowa providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Gastroenterology Physician. Verify directly:
How MIPS and board certification work
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).
Robert Graveline, M.D. appears in the CMS NPPES registry as a Gastroenterology Physician provider holding M.D. credentials at 3008 EVERGREEN CIR, Ames, IA, 50014, with a listed phone of (515) 292-5555. NPI 1336137306 was issued on 10/12/2005.
Medicare Part D records for calendar year 2023 show 1,521 prescription claims written by this provider, covering 692 Medicare beneficiaries and totaling roughly $558K in drug spend, split 25% brand-name and 75% generic by claim count.
Gastroenterology Physician is a mid-sized specialty nationwide, with 16,601 enrolled providers across 54 states and an average of 833 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
Provider Details
| NPI | 1336137306 |
|---|---|
| Specialty | Gastroenterology Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 10/12/2005 |
Brand vs generic prescribing mix · Above average
Robert Graveline, M.D. - brand share 25.0%
Gastroenterology Physician average
25% brand-name claims vs 75% generic, on 1,521 2023 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
1,521
Total Claims
$558K
Total Drug Cost
692
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 2,109
- Total Day Supply
- 47,214
- Brand vs Generic
- 25% brand / 75% generic
- Brand Drug Cost
- $486K
- Generic Drug Cost
- $72K
- Antibiotic Claims
- 16
Patient Demographics
- Average Patient Age
- 72.7 years
- Avg HCC Risk Score
- 1.09
- Gender Split
- 51% female / 49% male
- Age Distribution
- <65: 26, 65-74: 406, 75-84: 236, 85+: 24
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Robert Graveline, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Omeprazole
Omeprazole
362 claims
- Clenpiq 93
Clenpiq
93 claims
- Nortriptyline Hcl 77
Nortriptyline Hcl
77 claims
- Balsalazide Disodium 61
Balsalazide Disodium
61 claims
- Azathioprine 56
Azathioprine
56 claims
- Mesalamine 24
Mesalamine
24 claims
- Esomeprazole Magne… 23
Esomeprazole Magnesium
23 claims
- Pantoprazole Sodium 23
Pantoprazole Sodium
23 claims
| Drug | Claims |
|---|---|
| Omeprazole | 362 |
| Clenpiq Sod Picosulf/Mag Ox/Citric Ac | 93 |
| Nortriptyline Hcl | 77 |
| Balsalazide Disodium | 61 |
| Azathioprine | 56 |
| Mesalamine | 24 |
| Esomeprazole Magnesium | 23 |
| Pantoprazole Sodium | 23 |
| Sutab Sod Sulf/Pot Chloride/Mag Sulf | 22 |
| Linzess Linaclotide | 21 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Gastroenterology Physician Overview
How Robert Graveline, M.D. fits within the Gastroenterology Physician landscape nationally.
16,601
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider
Robert Graveline, M.D.'s 1,521 claims are above the specialty average of 833.
Nearby Gastroenterology Physician Providers in Iowa
Other clinicians with the same primary specialty enrolled in Iowa, drawn from the same CMS NPPES roster as Graveline.
Dr. Tyler Aasen
D.O.
West Des Moines, IA
Dr. Barakat Aburajab Altamimi
M.D.
Cedar Rapids, IA
Dr. Amol Agarwal
MD
Clive, IA
Dr. Naurang Agrawal
MD
Iowa City, IA
Dr. Bhavya Akhauri
M.D.
Cedar Rapids, IA
Compare Gastroenterology Physician nationally: see state-by-state distribution →
Before you book an appointment
Use this federal record as your verification checklist, not as a recommendation.
- Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
- Check the active license and any disciplinary history with the Iowa medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Gastroenterology Physician peer on Medicare volume and prescribing patterns. Compare providers
Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.
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Frequently Asked Questions
What is Robert Graveline, M.D.'s specialty? ▼
Robert Graveline, M.D. specializes in Gastroenterology Physician and practices in Ames, Iowa. Credentials: M.D..
How much does Robert Graveline, M.D. prescribe under Medicare Part D? ▼
In 2023, Robert Graveline, M.D. wrote 1,521 Medicare Part D claims totaling $558K in drug costs for 692 beneficiaries.
Where is Robert Graveline, M.D. located? ▼
Robert Graveline, M.D. is located at 3008 EVERGREEN CIR, Ames, IA, 50014. Phone: (515) 292-5555.
What is Robert Graveline, M.D.'s NPI number? ▼
Robert Graveline, M.D.'s National Provider Identifier (NPI) is 1336137306, issued on 10/12/2005.
Does Robert Graveline, M.D. prescribe more brand-name or generic drugs? ▼
Robert Graveline, M.D.'s prescribing is 25% brand-name and 75% generic drugs by claim count, with $486K in brand drug costs.
How many Gastroenterology Physician providers are there in the US? ▼
There are 16,601 Gastroenterology Physician providers across 54 states in the US. The average Gastroenterology Physician provider writes 833 Medicare Part D claims per year.
What drugs does Robert Graveline, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Robert Graveline, M.D.'s most frequently prescribed drugs include Omeprazole, Clenpiq, Nortriptyline Hcl. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Robert Graveline, M.D. accept Medicare? ▼
Robert Graveline, M.D. appears in CMS Medicare data with 1,521 Part D claims and 692 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Robert Graveline, M.D.'s credentials? ▼
Robert Graveline, M.D.'s NPI is 1336137306 with credentials M.D.. 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
View source datasets and methodology notes
- 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
Compiled from official public sources by the PlainDoctor editorial team.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 2026.