Physician Profile
Unclaimed ProfileAbout COLBY
John Benjamin Colby, MD, PhD practises diagnostic radiology in Greenbrae, CA. John is a 2014 graduate of University of California, Geffen School of Medicine. John is also listed as specialising in nuclear medicine. According to Medicare claims data, John cared for 5,162 Medicare patients across 5,541 services.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Areas of Expertise
Common questions
What kind of doctor is Dr. Colby?
Dr. Colby is a diagnostic radiology in Greenbrae, CA. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “DIAGNOSTIC RADIOLOGY”.
NPI registry
What is Dr. Colby's address?
Dr. Colby is listed at 250 BON AIR RD, Greenbrae, CA 94904. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. Colby?
The number on file is (415) 925-7301. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Colby's NPI number?
Dr. Colby's National Provider Identifier is 1700205374. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Colby train?
Dr. Colby attended University of California, Geffen School of Medicine, graduating in 2014. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Colby been practising?
Dr. Colby has 12 years experience. Calculated from a graduation year of 2014, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. Colby perform?
According to Medicare billing data, Dr. Colby performs imaging including x-ray of chest, 1 view and ct scan head or brain without contrast. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Colby confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Colby. If this is you, claiming it is free.
Guide.md
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (415) 925-7301
- Email not available
Practice Locations
250 BON AIR RD
Greenbrae, CA 94904
Procedures Most Often Billed to Medicare
5,541 services · 5,162 patients · 25 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| X-ray of chest, 1 view | Imaging | 71045 |
1,009 |
| Ct scan head or brain without contrast | Imaging | 70450 |
571 |
| Ct scan of abdomen and pelvis with contrast | Imaging | 74177 |
365 |
| Mri scan of brain without contrast | Imaging | 70551 |
280 |
| X-ray of shoulder, minimum of 2 views | Imaging | 73030 |
238 |
| Mri scan of brain before and after contrast | Imaging | 70553 |
220 |
| Mri scan of lower spinal canal without contrast | Imaging | 72148 |
200 |
| X-ray of hip, 2-3 views | Imaging | 73502 |
195 |
| X-ray of chest, 2 views | Imaging | 71046 |
188 |
| Ct scan of upper spine without contrast | Imaging | 72125 |
162 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
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Claim this profileRelated providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Other diagnostic radiology specialists in Greenbrae 8
Same specialty, same city.
Trained at University of California, Geffen School of Medicine 8
Other providers in the same specialty who trained at the same institution.
More connections — 16 related providers in 2 groups
Class of 2014 at University of California, Geffen School of Medicine 8
Providers who graduated from the same medical school in the same year.
Also performs X-ray of chest, 1 view 8
Providers in CA who bill this service to Medicare most often.
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.