Physician Profile
Unclaimed ProfileAbout CALLAN
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Areas of Expertise
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (240) 740-3000
- Email not available
Practice Locations
850 HUNGERFORD DR
Rockville, MD 20850
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other psychologists at this location 8
Same specialty, same street address — most likely the same department or group.
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 psychologists in Rockville 6
Same specialty, same city.
Common questions
What does Dr. Callan specialize in?
Dr. Callan is a psychologist in Rockville, MD. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “Psychologist”.
NPI registry
Where is Dr. Callan located?
Dr. Callan is listed at 850 HUNGERFORD DR, Rockville, MD 20850. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Callan's phone number?
The number on file is (240) 740-3000. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Callan's NPI number?
Dr. Callan's National Provider Identifier is 1821975970. 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
How long has Dr. Callan been practicing?
Dr. Callan has 1+ years experience. Registered with an NPI since 2025. National Provider Identifiers only began in 2005, so a provider who qualified earlier may have practiced for longer than this.
NPI registry
Has Dr. Callan confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Callan. If this is you, claiming it is free.
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Claim this profileProvider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.