SYBREY CALLWOOD CCC-SLP
NPI 1679429864
Speech-Language Pathologist in Oakland, CA

NPI Status: Active since March 09, 2026

Contact Information

4351 BROADWAY
OAKLAND, CA
ZIP 94611
Phone: (510) 208-7923

NPI Profile Information
Primary Taxonomy
NPI Validation
Other Providers Same Location
Frequently Asked Questions

Individual
Male
Speech-Language Pathologist

About SYBREY CALLWOOD

This page provides the complete NPI Profile along with additional information for Sybrey Callwood, a provider established in Oakland, California with a medical specialization in Speech-language Pathologist. The healthcare provider is registered in the NPI registry with number 1679429864 assigned on March 2026. The practitioner's primary taxonomy code is 235Z00000X with license number 35484 (CA). The provider is registered as an individual and his NPI record was last updated March 2026.

NPI: 1679429864
Provider Name: SYBREY CALLWOOD CCC-SLP
Gender: Male
Entity Type: Individual
Location Address: 4351 BROADWAY OAKLAND, CA 94611
Location Phone: (510) 208-7923
Mailing Address: 915 54TH ST OAKLAND, CA 94608
Mailing Phone: (510) 879-5003
Is Sole Proprietor?: No
Enumeration Date: 03-09-2026
Last Update Date: 03-09-2026
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Specialty - Primary Taxonomy

The NPI enumerator requires providers to submit at least one taxonomy code. A taxonomy code is a unique 10-character code that describes the healthcare provider type, classification, and the area of specialization. There could be only one primary taxonomy code per NPI record. For individual NPIs the license data is associated to the taxonomy code.

Classification: Speech-Language Pathologist
Taxonomy Code: 235Z00000X
Type: Speech, Language and Hearing Service Providers
License No.: 35484
License State: CA
Taxonomy Description: The speech-language pathologist is the professional who engages in clinical services, prevention, advocacy, education, administration, and research in the areas of communication and swallowing across the life span from infancy through geriatrics. Speech-language pathologists address typical and atypical impairments and disorders related to communication and swallowing in the areas of speech sound production, resonance, voice, fluency, language (comprehension and expression), cognition, and feeding and swallowing.

NPI NPI Number Validation

How NPI Validation Works

The NPI validation process uses the ISO-standard Luhn algorithm, a mathematical "handshake", to ensure that a provider's 10-digit ID is authentic and free of common typing errors.

To verify the NPI 1679429864, we treat the final digit (4) as the Check Digit—the target answer we need to reach. The process begins by taking the first nine digits and adding a constant value of 24, which accounts for the "80840" prefix required for all U.S. health identifiers. We then double every other digit starting from the right and sum the individual digits of those results together. For this specific NPI, that total comes to 76. The final step is to find the difference between that total and the next multiple of ten (80 - 76 = 4).

Digit-by-digit view

Use the first nine digits for the calculation. Starting from the right, double every other digit. The last digit is the check digit and is not part of the calculation.

Pos 1

Doubled → 2

Pos 2

Unchanged

Pos 3

Doubled → 14 → 1 + 4

Pos 4

Unchanged

Pos 5

Doubled → 8

Pos 6

Unchanged

Pos 7

Doubled → 18 → 1 + 8

Pos 8

Unchanged

Pos 9

Doubled → 12 → 1 + 2

Check

Target digit

Regular digit Doubled digit Check digit

Step 1: Double every other digit from the right

Starting with the rightmost digit of the first nine digits, double every other value. If doubling creates a two-digit number, add those digits together.

1 → 2 7 → 14 → 5 4 → 8 9 → 18 → 9 6 → 12 → 3

Step 2: Add all digits plus the NPI constant

Add the transformed values, the unchanged digits, and the constant 24.

2 + 6 + 1 + 4 + 9 + 8 + 2 + 1 + 8 + 8 + 1 + 2 + 24 = 76

Step 3: Find the amount needed to reach the next multiple of 10

The next multiple of ten after 76 is 80. The difference is the calculated check digit.

80 - 76 = 4

This NPI is valid

The calculated check digit is 4, which matches the last digit of 1679429864.