Dr. Robert J. Master , MD
Internal Medicine โข Cambridge, MA
9a Forest St
Cambridge, MA 021401501
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
-
Dr. Robert Master is listed in NPPES under Internal Medicine.
-
NPI assigned on October 18, 2006; this date does not establish years in practice.
-
Published CMS data list 117 Original Medicare Part B services in 2024.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Published rows only; this is not a quality measure.
-
Published Part B service records, 2024:
- 99349 โ Residence visit for established patient with moderate level of medical decision making, per day: 38 service units.
- 99495 โ Transitional care management services for problem of at least moderate complexity: 32 service units.
- 99348 โ Residence visit for established patient with low level of medical decision making, per day: 31 service units.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Units differ by code; these are not visits or a measure of quality.
CPTยฎ only copyright 2023 American Medical Association. All rights reserved. Service names are shortened from CPT Consumer Friendly Descriptors (CMS data, 2024). CPT notice
See all 4 records in the table ยท Guide: How to read Medicare Part B data
-
Published CMS data list 1,371 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024. Published rows only; this is not a quality measure.
-
Published Part D records, 2024:
- Atorvastatin Calcium โ 94 prescription fills, including refills.
- Amlodipine Besylate โ 79 prescription fills, including refills.
- Levothyroxine Sodium โ 74 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See all 52 records in the table ยท Guide: How to read Medicare Part D prescriber data
-
Fewer Medicare Part B services than 80% of clinicians listed under Internal Medicine in Cambridge, MA (2024, 147 clinicians with data). Median for this group: 379. Middle half: 167 to 1,007.
Fewer Medicare Part B services than 80% of clinicians listed under Internal Medicine in Massachusetts (2024, 3,795 clinicians with data). Median for this group: 524. Middle half: 200 to 1,073.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024. Billing and prescribing volume is not a quality rating.
-
Medicare Part B services went from 75 in 2023 to 117 in 2024.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2023โ2024.
Practice Location & Contact Primary Location
9a Forest St
Cambridge, MA 021401501
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
What Public CMS Data Show
Internal Medicine: NPPES taxonomy is a reported classification, not proof of board certification.
Medicare patients
63 people with Original Medicare in 2024
It gives a sense of how many people with Medicare this clinician treated that year.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider, 2024.
Medicare-allowed amount
About $16,605 in 2024
The total amount Medicare approved for these services in 2024. It includes what Medicare paid and what patients or their other insurance owed, such as the deductible and coinsurance.
It shows the total cost of this clinician's Original Medicare services under Medicare's fee rules.
What this does not show: Medicare-allowed amount
This is not the clinician's income. Part of it can go to a clinic or group practice, staff, equipment or drugs. It is not the price you will pay.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024.
Paid by Medicare
About $11,847 in 2024
The part of the Medicare-allowed amount that Medicare itself paid in 2024, after patients' deductibles and coinsurance.
The gap between the allowed amount and this number is roughly what patients and their other insurance paid.
What this does not show: Paid by Medicare
This is not the clinician's income and not a measure of quality.
Source: CMS, Medicare Physician & Other Practitioners โ by Provider and Service, 2024.
30-day fills
1,381 standardized 30-day fills in 2024
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$69,318 in 2024
The total cost of these prescriptions in 2024, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers โ by Provider and Drug, 2024.
Industry payments (Open Payments)
No Open Payments records are listed for this clinician for 2019โ2025.
NPI first issued
2006
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Medicare assignment not listed
CMS data do not show whether this clinician accepts Medicare assignment. This does not mean they do not accept Medicare. Ask the office.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, โDoes your provider accept Medicare as full payment?โ
No telehealth indicator
CMS shows this indicator only when recent Medicare claims include telehealth services. The clinician may still offer telehealth; ask the office.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Enrolled in Medicare (PECOS)
Dr. Master has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists Dr. Master as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Cambridge and Massachusetts
Billing and prescribing volume is not a quality rating.
Medicare Part B services
Fewer Medicare Part B services than 80% of clinicians listed under Internal Medicine in Cambridge, MA (2024, 147 clinicians with data). Median for this group: 379. Middle half: 167 to 1,007.
Fewer Medicare Part B services than 80% of clinicians listed under Internal Medicine in Massachusetts (2024, 3,795 clinicians with data). Median for this group: 524. Middle half: 200 to 1,073.
Medicare-allowed amount
A lower Medicare-allowed amount than 65% of clinicians listed under Internal Medicine in Cambridge, MA (2024, 147 clinicians with data). Median for this group: $32,929. Middle half: $13,311 to $91,263.
A lower Medicare-allowed amount than 75% of clinicians listed under Internal Medicine in Massachusetts (2024, 3,795 clinicians with data). Median for this group: $50,126. Middle half: $19,685 to $96,485.
Paid by Medicare
A lower Medicare payment amount than 65% of clinicians listed under Internal Medicine in Cambridge, MA (2024, 147 clinicians with data). Median for this group: $24,904. Middle half: $8,311 to $69,122.
A lower Medicare payment amount than 75% of clinicians listed under Internal Medicine in Massachusetts (2024, 3,795 clinicians with data). Median for this group: $38,152. Middle half: $14,838 to $74,912.
Medicare Part D prescriptions
Close to the middle for clinicians listed under Internal Medicine in Cambridge, MA (2024, 126 clinicians with data). Median for this group: 1,177. Middle half: 133 to 3,043.
Close to the middle for clinicians listed under Internal Medicine in Massachusetts (2024, 3,672 clinicians with data). Median for this group: 1,174. Middle half: 129 to 3,740.
Part D drug cost
Close to the middle for clinicians listed under Internal Medicine in Cambridge, MA (2024, 126 clinicians with data). Median for this group: $128,711. Middle half: $11,612 to $330,970.
Close to the middle for clinicians listed under Internal Medicine in Massachusetts (2024, 3,672 clinicians with data). Median for this group: $103,819. Middle half: $9,088 to $319,703.
301 active clinicians are listed under Internal Medicine with a practice address in Cambridge, MA (6,830 in Massachusetts).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Cambridge
24.6% of these 301 clinicians have the CMS telehealth indicator.
48.5% of these 301 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
-
Medicare Part B services
Medicare Part B services increased 56% from 75 in 2023 to 117 in 2024.
- 2023: 75
- 2024: 117
-
Medicare-allowed amount
Medicare-allowed amount increased 37% from $12,126 in 2023 to $16,605 in 2024.
- 2023: $12,126
- 2024: $16,605
-
Paid by Medicare
Paid by Medicare increased 27% from $9,351 in 2023 to $11,847 in 2024.
- 2023: $9,351
- 2024: $11,847
-
Medicare Part D prescriptions
Medicare Part D prescriptions increased 6132% from 22 in 2013 to 1,371 in 2024.
- 2013: 22
- 2014: 13
- 2015: 58
- 2024: 1,371
-
30-day fills
30-day fills increased 6176% from 22 in 2013 to 1,381 in 2024.
- 2013: 22
- 2014: 13
- 2015: 58
- 2024: 1,381
-
Part D drug cost
Part D drug cost went from $276 in 2013 to $69,318 in 2024.
- 2013: $276
- 2014: $79
- 2015: $422
- 2024: $69,318
Sources: CMS Medicare Physician & Other Practitioners (2024), CMS Medicare Part D Prescribers (2024), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo ยท Report an error.
Performed Procedures & Service Volume
CPTยฎ is a registered trademark of the American Medical Association. CPT codes, descriptions and other data only are copyright 2022โ2023 American Medical Association. All rights reserved. Applicable FARS/HHSARS apply. Descriptions of CPT codes are the AMA's CPT Consumer Friendly Descriptors as published by CMS in the Medicare Physician & Other Practitioners โ by Provider and Service data, 2023โ2024; they are plain-language summaries, not for clinical coding or documentation. HCPCS Level II codes and descriptions are from CMS. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.
| HCPCS Code | Services | Patients | Submitted Charge | Medicare Allowed |
|---|---|---|---|---|
|
99349
Residence visit for established patient with moderate level of medical decision making, per day, if using time, at least 40 minutes
|
38 | 26 | $190.21 | $130.19 |
|
99495
Transitional care management services for problem of at least moderate complexity
|
32 | 14 | $380.83 | $217.31 |
|
99348
Residence visit for established patient with low level of medical decision making, per day, if using time, at least 30 minutes
|
31 | 22 | $118.97 | $78.33 |
|
99344
Residence visit for new patient with moderate level of medical decision making, per day, if using time, at least 60 minutes
|
16 | 16 | $265.60 | $142.25 |
Source: CMS Part B by Provider and Service, 2024; services under 11 beneficiaries omitted by CMS. Privacy limits
Submitted charges are billed amounts, not a price quote for your visit.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Atorvastatin Calcium | Atorvastatin Calcium | 94 | 2,714 | $923.74 | 13 |
| Amlodipine Besylate | Amlodipine Besylate | 79 | 2,348 | $560.49 | โ |
| Levothyroxine Sodium | Levothyroxine Sodium | 74 | 2,286 | $727.12 | โ |
| Gabapentin | Gabapentin | 70 | 2,019 | $1,588.57 | โ |
| Tamsulosin Hcl | Tamsulosin Hcl | 59 | 1,641 | $724.78 | โ |
| Sertraline Hcl | Sertraline Hcl | 58 | 1,508 | $609.01 | โ |
| Omeprazole | Omeprazole | 58 | 1,683 | $703.56 | โ |
| Potassium Chloride | Potassium Chloride | 53 | 1,519 | $4,518.79 | โ |
| Trazodone Hcl | Trazodone Hcl | 52 | 1,494 | $382.98 | โ |
| Venlafaxine Hcl Er | Venlafaxine Hcl | 38 | 1,120 | $276.69 | โ |
| Metoprolol Tartrate | Metoprolol Tartrate | 33 | 914 | $336.52 | โ |
| Tramadol Hcl | Tramadol Hcl | 32 | 875 | $305.72 | โ |
| Metformin Hcl | Metformin Hcl | 32 | 948 | $1,098.02 | โ |
| Metoprolol Succinate | Metoprolol Succinate | 32 | 951 | $544.35 | โ |
| Atenolol | Atenolol | 27 | 716 | $109.37 | โ |
| Lorazepam | Lorazepam | 26 | 646 | $164.38 | โ |
| Alprazolam | Alprazolam | 25 | 750 | $158.48 | โ |
| Baclofen | Baclofen | 24 | 683 | $1,913.63 | โ |
| Clonazepam | Clonazepam | 24 | 704 | $254.04 | โ |
| Eliquis | Apixaban | 24 | 714 | $14,769.16 | โ |
| Nystatin | Nystatin | 22 | 414 | $482.62 | โ |
| Lisinopril | Lisinopril | 19 | 534 | $188.35 | โ |
| Famotidine | Famotidine | 19 | 602 | $121.22 | โ |
| Divalproex Sodium Er | Divalproex Sodium | 18 | 510 | $844.38 | โ |
| Mirtazapine | Mirtazapine | 18 | 540 | $328.27 | โ |
(top 25 shown)
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
Self-certified to NPPES: 2024-09-17NUCC Taxonomy Code: 207R00000X
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.
Additional State Medicaid & Healthcare Payer Identifiers
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - INTERNAL MEDICINE
I20050125000468
MA
7517916851
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
Career & Practice History Timeline
Changes recorded in monthly NPPES data files: addresses, names, credentials, specialties and NPI status
Registered at 9A FOREST ST, CAMBRIDGE, MA 021401501 (Tel: 6176806892)
Registered at 9A FOREST ST, CAMBRIDGE, MA 021401501 (Tel: 6176806892)
NPI status registered as active in NPPES database
Registered at 850 HARRISON AVE, 1 BMC PLACE, DOWLING NORTH, SUITE 5108, BOSTON, MA 021184001 (Tel: 6176387062)
Registered at 850 HARRISON AVE, 1 BMC PLACE, DOWLING NORTH, SUITE 5108, BOSTON, MA 021184001
Recorded as ROBERT MASTER, MD
Internal Medicine (license number reported to NPPES: MA 35355)
First registered as active Individual Practitioner in NPPES Database.
NPI Administrative Meta
Other Internal Medicine Providers in Cambridge
- Dr. Laima Zarins, MD
- Dr. Jeremy Keller, MD
- Dr. Stephanie Hastings, DO
- Dr. Christopher Dennis, MD
- Dr. Robert O'connor, MD
- Dr. Joan Savitsky, MD
Mailing Address
9a Forest St
Cambridge, MA 021401501
Phone: 6176806892