Provider Profile
Charles O. Masaki, MBCHB
Unclaimed ProfileAbout Charles Masaki
Based in Boston, MA, Charles O. Masaki, MBCHB is listed in the NPI registry under psychiatry. Charles is also listed as specializing in emergency medicine. Medicare claims data shows Charles provided 560 services to 370 patients. The services billed most often include subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes, subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes, and initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it — free, and no identity document with a practice or institutional email.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (617) 643-4294
- Email not available
Practice Locations
MASSACHUSETTS GENERAL HOSPITAL 55 FRUIT ST.
Boston, MA 02114
Conditions Commonly Evaluated or Treated
Within Psychiatry generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
Anxiety, trauma, and obsessive-compulsive
Mood disorders
Psychotic disorders
Substance-related and addictive
Addiction & Substance Use
Cognitive and adjustment
Eating Disorders
Eating, sleep, and somatic
Mood & Depression
Neurodevelopmental and behavioral
Personality and dissociative
Sleep & Wakefulness
Procedures & services
Most searched procedures
- Anxiety and depression treatment
- Cognitive behavioral therapy
- Medication management
- Psychiatric evaluation
- Telepsychiatry
Assessment
Addiction care
Addiction Medicine
Assessments
Brain stimulation
Consultations
Diagnostics
Inpatient care
Interventional psychiatry
Psychotherapy
Sleep Medicine
Specialized care
Therapy
Therapy and care
Procedures Most Often Billed to Medicare
560 services · 370 patients · 8 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Psychiatric diagnostic evaluation with medical services | Treatment | 90792 |
24 | As often as other peers in Psychiatry |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
241 | More often than most peers in Psychiatry |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
123 | More often than most peers in Psychiatry |
| Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | Office visit | 99223 |
60 | More often than most peers in Psychiatry |
| Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes | Office visit | 99222 |
59 | More often than most peers in Psychiatry |
| Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes | Office visit | 99231 |
25 | Less often than most peers in Psychiatry |
| Emergency department visit with moderate level of medical decision making | Office visit | 99284 |
17 | As often as other peers in Psychiatry |
| Emergency department visit with high level of medical decision making | Office visit | 99285 |
11 | Less often than most peers in Psychiatry |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
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 psychiatrists at this location 4
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 2
Clinically related specialties at the same address — the people this provider most likely works alongside.
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.
More connections — 32 related providers in 4 groups
Other psychiatrists in Boston 8
Same specialty, same city.
Trained at Other 8
Other providers in the same specialty who trained at the same institution.
Class of 2011 at Other 8
Providers who graduated from the same medical school in the same year.
Also performs Psychiatric diagnostic evaluation with medical services 8
Providers in MA who bill this service to Medicare most often.
Common questions
What kind of doctor is Charles O. Masaki?
Charles O. Masaki is a psychiatrist in Boston, MA. That is the designation recorded for this NPI in the federal registry, where it is listed as “Psychiatry”.
NPI registry
What is Charles O. Masaki's address?
Charles O. Masaki is listed at Massachusetts General Hospital 55 Fruit St., Boston, MA 02114. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Charles O. Masaki?
The number on file is (617) 643-4294. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is the NPI for Charles O. Masaki?
Charles O. Masaki's National Provider Identifier is 1821518051. 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 Charles O. Masaki train?
Charles O. Masaki attended Other, graduating in 2011. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Charles O. Masaki have?
Charles O. Masaki has 15 years experience. Calculated from a graduation year of 2011, reported in the CMS National Downloadable File.
CMS public data
What procedures does Charles O. Masaki perform?
According to Medicare billing data, Charles O. Masaki provides treatments such as psychiatric diagnostic evaluation with medical services, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Charles O. Masaki's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Charles O. Masaki. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.