Gillian Mayersohn, PSY.D., ABPP
Gillian Mayersohn, PSY.D., ABPP is a Clinical Psychologist in Saint Louis, MO, registered under NPI 1265917884.
Getting there
The practice address on file is 1465 S GRAND BLVD, Saint Louis, MO 63104. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 2018033534 | MO | Clinical Psychologist primary |
This provider holds licence 2018033534 issued in MO. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Clinical Psychologist
- PAC ID
- 4183960263
- Enrollment ID
- I20190110000785
Medicare enrolment is recorded as approved under the provider type Practitioner - Clinical Psychologist. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Clinical covers
A psychologist who provides continuing and comprehensive mental and behavioral health care for individuals and families; consultation to agencies and communities; training, education and supervision; and research-based practice. It is a specialty in breadth -- one that is broadly inclusive of severe psychopathology -- and marked by comprehensiveness and integration of knowledge and skill from a broad array of disciplines within and outside of psychology proper. The scope of clinical psychology encompasses all ages, multiple diversities and varied systems. NUCC Health Care Provider Taxonomy, code 103TC0700X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1265917884 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Sep 28, 2018 |
| Last updated | Apr 28, 2025 |
| Status | Active |
| Sole proprietor | No |
| Gender | Female |
| Credential | PSY.D., ABPP |
| Practice address |
1465 S GRAND BLVD Saint Louis, MO 63104 (314) 577-5667 |
| Mailing address |
1 CHILDRENS PL STE 3N14 Saint Louis, MO 63110 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 2 | 6 | 5 | 9 | 1 | 7 | 8 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 2 | 3 | 5 | 9 | 1 | 5 | 8 | 7 |
Sum = 66 · next multiple of 10 = 70 · check digit = 4 · actual last digit = 4
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.