Drew Messer, J.D. PH.D.
Drew Messer, J.D. PH.D. is a Clinical Child & Adolescent Psychologist in Williamsville, NY, registered under NPI 1972574473. This provider registers 4 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 8616 MAIN STREET STE 4, Williamsville, NY 14221. 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 |
|---|---|---|
| 016499 | NY | Clinical Child & Adolescent Psychologist primary |
| 048-0000679 | VT | Addiction (Substance Use Disorder)… |
| 071-005496 | IL | Clinical Psychologist |
| 048-0000679 | VT | Forensic Psychologist |
Licences are recorded in 3 states: NY, VT, IL. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Order And Referring Only - Clinical Psychologist
- PAC ID
- 4183723711
- Enrollment ID
- I20210127002608
Medicare enrolment is recorded as approved under the provider type Order And Referring Only - 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.
Licensed in 3 states
This provider holds licences in 3 states: Illinois, New York and Vermont. The practice address on file is in Williamsville, NY, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
- Licence
- 016499
- Specialty
- Clinical Child & Adolescent Psychologist
- Licence
- 048-0000679
- Specialty
- Addiction (Substance Use Disorder)…
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Clinical Child & Adolescent covers
A psychologist who develops and applies scientific knowledge to the delivery of psychological services to infants, toddlers, children and adolescents within their social context. Of particular importance to the specialty of clinical child psychology is an understanding of the basic psychological needs of children and adolescents, and how the family and other social contexts influence the socio-emotional adjustment, cognitive development, behavioral adaptation and health status of children and adolescents. NUCC Health Care Provider Taxonomy, code 103TC2200X
All registered taxonomy codes
This provider registers 4 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 103TC2200X | Clinical Child & Adolescent Psychologist Clinical Child & Adolescent | 016499 | NY | primary |
| 103TA0400X | Addiction (Substance Use Disorder) Psychologist Addiction (Substance Use Disorder) | 048-0000679 | VT | |
| 103TC0700X | Clinical Psychologist Clinical | 071-005496 | IL | |
| 103TF0200X | Forensic Psychologist Forensic | 048-0000679 | VT |
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 | 1972574473 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Feb 1, 2006 |
| Last updated | Apr 24, 2014 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | J.D. PH.D. |
| Practice address |
8616 MAIN STREET STE 4 Williamsville, NY 14221 (716) 961-9435 Fax (716) 961-9436 |
| Mailing address |
8616 MAIN STREET STE. 4 Williamsville, NY 14221 |
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 | 9 | 7 | 2 | 5 | 7 | 4 | 4 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 9 | 5 | 2 | 1 | 7 | 8 | 4 | 5 |
Sum = 67 · next multiple of 10 = 70 · check digit = 3 · actual last digit = 3
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.