Robert Amster Md-Grossmont Inc
NPI 1528365731 · Emergency Medicine Physician · Tustin, CA
Robert Amster Md-Grossmont Inc is a Emergency Medicine Physician organization in Tustin, CA (NPI 1528365731).
Provider details
- NPI number
- 1528365731
- Entity type
- Organization
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Organization subpart
- No
- Authorized official
- Roibert Amster, Owner(714) 389-5700
- License
- G34265 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
15 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2011-02-24
- Last updated
- 2011-02-24
Frequently asked questions
- What is Robert Amster Md-Grossmont Inc's NPI number?
- Robert Amster Md-Grossmont Inc's National Provider Identifier (NPI) is 1528365731, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is Robert Amster Md-Grossmont Inc?
- Robert Amster Md-Grossmont Inc is classified in the NPPES registry as Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Robert Amster Md-Grossmont Inc located?
- Robert Amster Md-Grossmont Inc's practice location on file with NPPES is 18231 Irvine Blvd, Tustin, CA 92780-3432.
- What is Robert Amster Md-Grossmont Inc's phone number?
- The practice phone number listed in the NPPES registry for Robert Amster Md-Grossmont Inc is (714) 389-5700.
- Who is the authorized official for Robert Amster Md-Grossmont Inc?
- The authorized official listed on Robert Amster Md-Grossmont Inc's NPPES record is Roibert Amster, Owner. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is Robert Amster Md-Grossmont Inc's NPI active?
- Yes — Robert Amster Md-Grossmont Inc's NPI (1528365731) is active in the NPPES registry as of the last update on 2011-02-24.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.